Citigroup Commercial Mortgage Trust 2015-GC31

26/08/2024 | Press release | Distributed by Public on 26/08/2024 18:45

Asset Backed Issuer Distribution Report Form 10 D


Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
STATEMENT TO NOTEHOLDERS
August 12, 2024
TRANSACTION PARTIES
Depositor: Citigroup Commercial Mortgage Securities Inc.
Master Servicer: Wells Fargo Bank, National Association
Certificate Administrator: Citibank, N.A.
Trustee: Deutsche Bank Trust Company Americas
Special Servicer: Torchlight Loan Services, LLC
Operating Advisor: Pentalpha Surveillance LLC.
Danny Lee Citibank, Agency and Trust
(212) 816-4936 388 Greenwich Street Trading, 4th Floor
[email protected] New York, NY 10013
TABLE OF CONTENTS
1 . Distribution Summary 2
1.1 . Summary 2
1.2 . Factors 3
1.3 . Interest Detail 4
1.4 . Interest Shortfall Detail 5
1.5 . Principal Detail 6
2 . Reconciliation Detail 7
3 . Other Information 8
4 . Stratification Detail 9
5 . Mortgage Loan Detail 14
6 . NOI Detail 16
7 . Delinquency Loan Detail 18
8 . Collateral Performance Delinquency and Loan Status Detail 19
9 . Appraisal Reduction Detail 20
10 . Historical Appraisal Reduction Detail 21
11 . Loan Modification Detail 23
12 . Historical Loan Modification Detail 24
13 . Specially Serviced Loan Detail 26
14 . Historical Specially Serviced Loan Detail 27
15 . Unscheduled Principal Detail 31
16 . Historical Unscheduled Principal Detail 32
17 . Liquidated Loan Detail 33
18 . Historical Liquidated Loan Detail 34
19 . CREFC Investor Reporting Package Legends 35
20 . Notes 36
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
DISTRIBUTION SUMMARY
August 12, 2024
Accrual Other Non-Cash
Original Prior Pass-Through Day Interest (As Interest) Principal Total Realized Loss Balance Current
Class Balance Balance Rate Count Distributed Distributed Distributed Distributed /(Recovery) Change Balance
Class A-1 28,330,000.00 - 1.637000 % 30/360 - - - - - - -
Class A-2 2,298,000.00 - 3.084000 % 30/360 - - - - - - -
Class A-3 160,000,000.00 144,903,327.65 3.497000 % 30/360 422,272.45 - - 422,272.45 - - 144,903,327.65
Class A-4 268,724,000.00 268,724,000.00 3.762000 % 30/360 842,449.74 - - 842,449.74 - - 268,724,000.00
Class A-AB 46,974,000.00 6,399,783.29 3.431000 % 30/360 18,298.05 - 872,446.71 890,744.76 - - 5,527,336.58
Class A-S 58,763,000.00 58,763,000.00 4.165580 % 30/360 203,984.98 - - 203,984.98 - - 58,763,000.00
Class B 42,871,000.00 42,871,000.00 4.166580 % 30/360 148,854.54 - - 148,854.54 - - 42,871,000.00
Class C 33,852,000.00 33,852,000.00 4.166580 % 30/360 88,627.88 - - 88,627.88 - - 33,852,000.00
Class D 24,284,000.00 24,284,000.00 4.166580 % 30/360 - - - - - - 24,284,000.00
Class E 11,000,000.00 11,000,000.00 4.166580 % 30/360 - - - - - - 11,000,000.00
Class F 14,864,000.00 14,864,000.00 4.166580 % 30/360 - - - - - - 14,864,000.00
Class G 12,231,000.00 12,231,000.00 4.166580 % 30/360 - - - - - - 12,231,000.00
Class H 19,132,869.00 18,096,204.22 4.166580 % 30/360 - - - - - - 18,096,204.22
Class S - - 0.000000 % 30/360 - - - - - - -
Class R - - 0.000000 % 30/360 - - - - - - -
Total 723,323,869.00 635,988,315.16 1,724,487.64 - 872,446.71 2,596,934.35 - - 635,115,868.45
Notional
Class X-A 565,089,000.00 478,790,110.94 0.439673 % 30/360 175,425.84 - - 175,425.84 - (872,446.71 ) 477,917,664.23
Grand Total 1,288,412,869.00 1,114,778,426.10 1,899,913.48 - 872,446.71 2,772,360.19 - (872,446.71 ) 1,113,033,532.68
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
DISTRIBUTION SUMMARY - FACTORS
August 12, 2024
Other Non-Cash
Record Interest (As Interest) Principal Total Realized Loss Balance Current
Class CUSIP Date Distributed Distributed Distributed Distributed /(Recovery) Change Balance
Class A-1 17323 YAA7 07/31/2024 - - - - - - -
Class A-2 17323 YAB5 07/31/2024 - - - - - - -
Class A-3 17323 YAC3 07/31/2024 2.63920281 - - 2.63920281 - - 905.64579781
Class A-4 17323 YAD1 07/31/2024 3.13500000 - - 3.13500000 - - 1,000.00000000
Class A-AB 17323 YAE9 07/31/2024 0.38953570 - 18.57297037 18.96250607 - - 117.66799889
Class A-S 17323 YAF6 07/31/2024 3.47131664 - - 3.47131664 - - 1,000.00000000
Class X-A 17323 YAL3 07/31/2024 0.31043931 - - 0.31043931 - - 845.73874952
Class B 17323 YAG4 07/31/2024 3.47214994 - - 3.47214994 - - 1,000.00000000
Class C 17323 YAH2 07/31/2024 2.61809878 - - 2.61809878 - - 1,000.00000000
Class D 17323 YAJ8 07/31/2024 - - - - - - 1,000.00000000
Class E 17323 YAN9 07/31/2024 - - - - - - 1,000.00000000
Class F 17323 YAQ2 07/31/2024 - - - - - - 1,000.00000000
Class G 17323 YAS8 07/31/2024 - - - - - - 1,000.00000000
Class H 17323 YAU3 07/31/2024 - - - - - - 945.81759902
Class S 17323 YAW9 07/31/2024 - - - - - - -
Class R 17323 YAY5 07/31/2024 - - - - - - -
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
DISTRIBUTION INFORMATION - INTEREST DETAIL
August 12, 2024
Rate Interest Shortfall Paid
Accrual Net Non Carry Basis Carry
Class Uncapped Capped Next Dates Accrued Deferred Recovered Forward Risk Accrued Forward Basis Risk Total
Class A-1 1.63700 % 1.63700 % 1.63700 % 07/01-07/31 - - - - - - - - -
Class A-2 3.08400 % 3.08400 % 3.08400 % 07/01-07/31 - - - - - - - - -
Class A-3 3.49700 % 3.49700 % 3.49700 % 07/01-07/31 422,272.45 - - - - 422,272.45 - - 422,272.45
Class A-4 3.76200 % 3.76200 % 3.76200 % 07/01-07/31 842,449.74 - - - - 842,449.74 - - 842,449.74
Class A-AB 3.43100 % 3.43100 % 3.43100 % 07/01-07/31 18,298.05 - - - - 18,298.05 - - 18,298.05
Class A-S 4.16558 % 4.16558 % 4.16558 % 07/01-07/31 203,984.98 - - - - 203,984.98 - - 203,984.98
Class B 4.16658 % 4.16658 % 4.16658 % 07/01-07/31 148,854.54 - - - - 148,854.54 - - 148,854.54
Class C 4.16658 % 4.16658 % 4.16658 % 07/01-07/31 117,539.22 - - 29,308.58 - 88,627.88 - - 88,627.88
Class D 4.16658 % 4.16658 % 4.16658 % 07/01-07/31 84,317.69 - - 85,493.09 - - - - -
Class E 4.16658 % 4.16658 % 4.16658 % 07/01-07/31 38,193.65 - - 38,848.47 - - - - -
Class F 4.16658 % 4.16658 % 4.16658 % 07/01-07/31 51,610.04 - - 52,506.12 - - - - -
Class G 4.16658 % 4.16658 % 4.16658 % 07/01-07/31 42,467.87 - - 44,967.46 - - - - -
Class H 4.16658 % 4.16658 % 4.16658 % 07/01-07/31 62,832.73 - - 68,577.63 - - - - -
Class S 0.00000 % 0.00000 % 0.00000 % 07/01-07/31 - - - - - - - - -
Class R 0.00000 % 0.00000 % 0.00000 % 07/01-07/31 - - - - - - - - -
Total 2,032,820.96 - - 319,701.35 - 1,724,487.64 - - 1,724,487.64
Notional
Class X-A 0.43967 % 0.43967 % 0.43967 % 07/01-07/31 175,425.84 - - - - 175,425.84 - - 175,425.84
Total 175,425.84 - - - - 175,425.84 - - 175,425.84
Grand Total 2,208,246.80 - - 319,701.35 - 1,899,913.48 - - 1,899,913.48
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
DISTRIBUTION INFORMATION - INTEREST SHORTFALL DETAIL
August 12, 2024
Non-Recov Shortfall Carry Forward Interest Basis Risk Shortfall
Other
Class PPIS SSRA Shortfall Prior Int. on Prior New Paid Outstanding Prior Int. on Prior New Paid Outstanding
Class A-1 - - - - - - - - - - - - -
Class A-2 - - - - - - - - - - - - -
Class A-3 - - - - - - - - - - - - -
Class A-4 - - - - - - - - - - - - -
Class A-AB - - - - - - - - - - - - -
Class A-S - - - - - - - - - - - - -
Class B - - - - - - - - - - - - -
Class C - - - 114,407.73 397.24 28,911.34 - 143,716.31 - - - - -
Class D - - - 338,523.55 1,175.40 84,317.69 - 424,016.64 - - - - -
Class E - - - 188,593.32 654.82 38,193.65 - 227,441.79 - - - - -
Class F - - - 258,075.83 896.08 51,610.04 - 310,581.95 - - - - -
Class G - - - 719,895.75 2,499.59 42,467.87 - 764,863.21 - - - - -
Class H - - - 1,654,564.87 5,744.90 62,832.73 - 1,723,142.50 - - - - -
Class S - - - - - - - - - - - - -
Class R - - - - - - - - - - - - -
Total - - - 3,274,061.05 11,368.03 308,333.32 - 3,593,762.40 - - - - -
Notional
Class X-A - - - - - - - - - - - - -
Total - - - - - - - - - - - - -
Grand Total - - - 3,274,061.05 11,368.03 308,333.32 - 3,593,762.40 - - - - -
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
DISTRIBUTION INFORMATION - PRINCIPAL DETAIL
August 12, 2024
Non-Cash Cumulative
Prior Principal Accreted Realized Loss Balance Current Realized Class % Class % Sub % Sub %
Class Balance Distributed Principal /(Recovery) Change Balance Loss Original Current Original Current
Class A-1 - - - - - - - 0.00 % 0.00 % 0.00 % 0.00 %
Class A-2 - - - - - - - 0.00 % 0.00 % 0.00 % 0.00 %
Class A-3 144,903,327.65 - - - - 144,903,327.65 - 0.00 % 0.00 % 0.00 % 0.00 %
Class A-4 268,724,000.00 - - - - 268,724,000.00 - 0.00 % 0.00 % 0.00 % 0.00 %
Class A-AB 6,399,783.29 872,446.71 - - - 5,527,336.58 - 0.00 % 0.00 % 0.00 % 0.00 %
Class A-S 58,763,000.00 - - - - 58,763,000.00 - 0.00 % 0.00 % 0.00 % 0.00 %
Class B 42,871,000.00 - - - - 42,871,000.00 - 0.00 % 0.00 % 0.00 % 0.00 %
Class C 33,852,000.00 - - - - 33,852,000.00 - 0.00 % 0.00 % 0.00 % 0.00 %
Class D 24,284,000.00 - - - - 24,284,000.00 - 0.00 % 0.00 % 0.00 % 0.00 %
Class E 11,000,000.00 - - - - 11,000,000.00 - 0.00 % 0.00 % 0.00 % 0.00 %
Class F 14,864,000.00 - - - - 14,864,000.00 - 0.00 % 0.00 % 0.00 % 0.00 %
Class G 12,231,000.00 - - - - 12,231,000.00 - 0.00 % 0.00 % 0.00 % 0.00 %
Class H 18,096,204.22 - - - - 18,096,204.22 1,036,664.78 0.00 % 0.00 % 0.00 % 0.00 %
Class S - - - - - - - 0.00 % 0.00 % 0.00 % 0.00 %
Class R - - - - - - - 0.00 % 0.00 % 0.00 % 0.00 %
Total 635,988,315.16 872,446.71 - - - 635,115,868.45 1,036,664.78 0.00 % 0.00 %
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
RECONCILIATION DETAIL
August 12, 2024
SOURCE OF FUNDS ALLOCATION OF FUNDS
Interest Funds Available Scheduled Fees
Scheduled Interest 1,934,114.72 Servicing Fee 6,325.65
Prepayment Interest Shortfall - Trustee/Certificate Administrator Fee 1,862.03
Interest Adjustments - Operating Advisor Fee 711.95
ASER Amount - CREFC Intellectual Property Royalty License Fee 273.83
Realized Loss in Excess of Principal Balance -
Total Scheduled Fees 9,173.46
Total Interest Funds Available 1,934,114.72 Additional Fees, Expenses, etc.
Principal Funds Available Additional Servicing Fee -
Scheduled Principal 872,446.71 Special Servicing Fee 25,027.78
Unscheduled Principal Collections - Work-out Fee -
Repurchased Principal - Liquidation Fee -
Substitution Principal - Trust Fund Expenses -
Other Principal - Trust Advisor Expenses -
Reimbursement of Interest on Advances to the Servicer -
Total Principal Funds Available 872,446.71
Borrower Reimbursable Trust Fund Expenses -
Other Funds Available
Other Expenses -
Yield Maintenance Charges -
Withdrawal of Withheld Amounts from the Interest Reserve Total Additional Fees, Expenses, etc. 25,027.78
Account -
Distributions
Deposit of Withheld Amounts to the Interest Reserve Account -
Interest Distribution 1,899,913.48
Current Period Adjustment to Loan - Other -
Principal Distribution 872,446.71
Total Other Funds Available - Yield Maintenance Charge Distribution -
Total Distributions 2,772,360.19
Total Funds Available 2,806,561.43 Total Funds Allocated 2,806,561.43
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
OTHER INFORMATION
Interest Reserve Account Information
August 12, 2024
Beginning Interest Reserve Account Balance 0.00
Deposit of Withheld Amounts to the Interest Reserve Account 0.00
Withdrawal of Withheld Amounts from the Interest Reserve Account 0.00
Ending Interest Reserve Account Balance 0.00
Excess Liquidation Proceeds Reserve Account Information
Beginning Excess Liquidation Proceeds Reserve Account Balance 0.00
Deposit to the Excess Liquidation Proceeds Reserve Account 0.00
Withdrawal from the Excess Liquidation Proceeds Reserve Account 0.00
Ending Excess Liquidation Proceeds Reserve Account Balance 0.00
Collateral Information
% of Cut-Off Principal Balance Outstanding 87.805186 %
Controlling Class Information
Controlling Class is Class F.
Control Termination Event is in Effect.
Identification of the current Controlling Class Representative has not been provided.
There Are No Disclosable Special Servicer Fees.
Non-Active Exchangeable Certificates
Class PEZ Beginning Balance 135,486,000.00
Class PEZ Ending Balance 135,486,000.00
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
STRATIFICATION DETAIL
August 12, 2024
Anticipated Remaining Term
Anticipated Remaining Asset Ending Scheduled % of Wtd Avg
Term Range Count Balance Agg.Bal. WAC WAM DSCR
60 Months or Less 46 535,115,868.45 84.25 4.1904 9 1.873354
61 to 90 Months 1 100,000,000.00 15.75 3.2950 69 -2.418000
91 Months or Greater 0 0.00 0.00 0.0000 0 0.000000
Total 47 635,115,868.45 100.00 4.0494 18 1.197674
Debt Service Coverage Ratio
Debt Service Coverage Asset Ending Scheduled % of Wtd Avg
Ratio Range Count Balance Agg.Bal. WAC WAM DSCR
1.250 or Less 6 143,660,596.14 22.62 3.6455 51 -1.344475
1.251 to 1.500 9 171,983,312.90 27.08 4.2467 9 1.373388
1.501 to 1.750 6 23,666,124.28 3.73 4.5421 9 1.601053
1.751 to 2.000 9 105,743,818.71 16.65 4.0787 8 1.923864
2.001 to 2.250 4 90,426,071.26 14.24 4.0922 8 2.061043
2.251 to 2.500 5 45,184,869.74 7.11 4.1148 9 2.377596
2.501 to 2.750 4 25,227,202.43 3.97 4.2188 10 2.607351
2.751 to 3.000 1 10,146,244.48 1.60 3.9500 9 2.839800
3.001 to 3.250 0 0.00 0.00 0.0000 0 0.000000
3.251 to 3.500 1 4,618,723.59 0.73 3.9570 10 3.465600
3.501 to 3.750 1 5,458,904.92 0.86 4.1905 3 3.506400
3.751 to 4.000 0 0.00 0.00 0.0000 0 0.000000
4.001 or Greater 1 9,000,000.00 1.42 3.9300 10 5.860200
Total 47 635,115,868.45 100.00 4.0494 18 1.197674
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
STRATIFICATION DETAIL
August 12, 2024
Ending Schedule Balance
Ending Schedule Balance Asset Ending Scheduled % of Wtd Avg
Range Count Balance Agg.Bal. WAC WAM DSCR
1 to 5,000,000 17 57,409,668.00 9.04 4.4574 8 1.915421
10,000,001 to 15,000,000 4 47,579,680.16 7.49 4.2600 9 1.527394
15,000,001 to 20,000,000 2 36,583,818.12 5.76 4.2520 8 1.399261
20,000,001 to 25,000,000 2 43,262,986.21 6.81 4.0850 10 1.960152
25,000,001 to 30,000,000 3 76,825,583.09 12.10 4.2314 9 1.623748
30,000,001 to 35,000,000 0 0.00 0.00 0.0000 0 0.000000
35,000,001 to 40,000,000 1 39,689,063.85 6.25 4.1300 10 1.284900
40,000,001 to 45,000,000 0 0.00 0.00 0.0000 0 0.000000
45,000,001 to 50,000,000 0 0.00 0.00 0.0000 0 0.000000
5,000,001 to 10,000,000 15 103,036,318.05 16.22 4.2746 9 2.385036
50,000,001 to 55,000,000 0 0.00 0.00 0.0000 0 0.000000
55,000,001 to 60,000,000 1 58,728,750.97 9.25 4.0975 9 2.073600
60,000,001 to 65,000,000 0 0.00 0.00 0.0000 0 0.000000
65,000,001 to 70,000,000 0 0.00 0.00 0.0000 0 0.000000
70,000,001 to 75,000,000 1 72,000,000.00 11.34 3.9085 8 1.952300
75,000,001 to 80,000,000 0 0.00 0.00 0.0000 0 0.000000
80,000,001 to 85,000,000 0 0.00 0.00 0.0000 0 0.000000
85,000,000+ 1 100,000,000.00 15.75 3.2950 69 -2.418000
Total 47 635,115,868.45 100.00 4.0494 18 1.197674
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
STRATIFICATION DETAIL
August 12, 2024
Loan Rate
Asset Ending Scheduled % of Wtd Avg
Loan Rate Range Count Balance Agg.Bal. WAC WAM DSCR
4.00 or Less 9 261,853,857.17 41.23 3.6844 31 0.517701
4.01 to 4.25 9 155,103,122.61 24.42 4.1258 9 1.795553
4.26 to 4.50 20 173,295,154.36 27.29 4.3687 9 1.569901
4.51 to 4.75 7 33,939,178.74 5.34 4.6341 8 1.636659
4.76 to 5.00 2 10,924,555.57 1.72 4.8349 8 1.739253
5.01 to 5.25 0 0.00 0.00 0.0000 0 0.000000
5.26 to 5.50 0 0.00 0.00 0.0000 0 0.000000
5.51 to 5.75 0 0.00 0.00 0.0000 0 0.000000
5.76 to 6.00 0 0.00 0.00 0.0000 0 0.000000
6.01 to 6.25 0 0.00 0.00 0.0000 0 0.000000
6.26 to 6.50 0 0.00 0.00 0.0000 0 0.000000
6.51 to 6.75 0 0.00 0.00 0.0000 0 0.000000
6.76 to 7.00 0 0.00 0.00 0.0000 0 0.000000
7.01 or Greater 0 0.00 0.00 0.0000 0 0.000000
Total 47 635,115,868.45 100.00 4.0494 18 1.197674
Property Type
Asset Ending Scheduled % of Wtd Avg
Property Type Range Count Balance Agg.Bal. WAC WAM DSCR
Industrial 1 5,203,951.15 0.82 4.2800 10 2.594700
Lodging 2 12,074,097.85 1.90 4.3887 10 1.295818
Mixed Use 4 102,642,112.14 16.16 4.1543 9 1.819546
Multifamily 10 76,465,584.99 12.04 4.3235 8 1.861844
Office 6 179,674,894.97 28.29 3.6504 42 -0.594693
Other 9 155,190,000.85 24.43 4.1266 8 1.827656
Retail 12 90,083,338.65 14.18 4.2840 9 1.812916
Self Storage 3 13,781,887.85 2.17 4.1642 9 4.519549
Total 47 635,115,868.45 100.00 4.0494 18 1.197674
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
STRATIFICATION DETAIL
August 12, 2024
Remaining Amortization Term
Remaining Amortization Asset Ending Scheduled % of Wtd Avg
Term Range Count Balance Agg.Bal. WAC WAM DSCR
240 Months or Less 8 216,345,493.69 34.06 3.6515 36 0.129000
241 to 270 Months 39 418,770,374.76 65.94 4.2550 9 1.749773
271 to 300 Months 0 0.00 0.00 0.0000 0 0.000000
301 Months or Greater 0 0.00 0.00 0.0000 0 0.000000
Total 47 635,115,868.45 100.00 4.0494 18 1.197674
Seasoning
Asset Ending Scheduled % of Wtd Avg
Seasoning Range Count Balance Agg.Bal. WAC WAM DSCR
12 Months or Less 0 0.00 0.00 0.0000 0 0.000000
13 to 24 Months 0 0.00 0.00 0.0000 0 0.000000
25 to 36 Months 0 0.00 0.00 0.0000 0 0.000000
37 to 48 Months 0 0.00 0.00 0.0000 0 0.000000
49 Months or Greater 47 635,115,868.45 100.00 4.0494 18 1.197674
Total 47 635,115,868.45 100.00 4.0494 18 1.197674
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
STRATIFICATION DETAIL
August 12, 2024
State
Asset Ending Scheduled % of Wtd Avg
State Range Count Balance Agg.Bal. WAC WAM DSCR
California 4 91,814,626.34 14.46 4.1783 9 1.631090
Colorado 1 2,570,952.22 0.40 4.3100 10 1.555000
Florida 6 34,880,809.99 5.49 4.3807 9 1.830250
Hawaii 1 9,000,000.00 1.42 3.9300 10 5.860200
Illinois 1 100,000,000.00 15.75 3.2950 69 -2.418000
Iowa 1 3,130,681.40 0.49 4.3900 10 1.636700
Kansas 1 5,086,445.01 0.80 4.4900 10 2.276100
Louisiana 1 7,568,214.12 1.19 4.1730 9 1.282300
Maryland 1 11,544,193.27 1.82 3.9970 9 1.250500
Michigan 3 14,652,051.81 2.31 4.4902 8 2.110787
Minnesota 0 0.00 0.00 0.0000 0 0.000000
Nebraska 1 9,503,145.63 1.50 4.4100 10 1.225700
Nevada 1 5,458,904.92 0.86 4.1905 3 3.506400
New Jersey 2 27,624,014.02 4.35 4.4369 9 1.472807
North Carolina 1 3,731,397.93 0.59 4.4000 9 1.390200
Ohio 1 2,062,129.24 0.32 4.7000 9 1.911400
Oklahoma 2 30,478,022.41 4.80 4.0003 9 1.804986
Oregon 1 9,911,352.16 1.56 4.1540 7 2.293500
Pennsylvania 1 5,925,093.28 0.93 4.3000 10 2.348200
Rhode Island 1 5,155,000.00 0.81 4.1400 10 1.841700
South Carolina 1 2,607,412.09 0.41 4.7200 10 2.101300
Texas 6 97,221,421.76 15.31 4.1482 9 1.949026
Various 9 155,190,000.85 24.43 4.1266 8 1.827656
Total 47 635,115,868.45 100.00 4.0494 18 1.197674
Reports Available at sf.citidirect.com v. 21.09.28 Page 13 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
MORTGAGE LOAN DETAIL
August 12, 2024
Prop Paid Beginning Ending Payment Workout Mod
Type Through Gross Interest Principal Scheduled Scheduled Maturity Status Strategy Code
Loan ID OMCR (1) City State Date Coupon Payment Payment Balance Balance Date (2 ) (3 ) (4 )
304101385 1 OF Chicago IL 10/06/2021 3.29500 % - - 100,000,000.00 100,000,000.00 05/06/2030 3 1 0
304140010 10 RT San Diego CA 08/06/2024 3.90100 % 74,574.12 - 22,200,000.00 22,200,000.00 06/06/2025 0 0 0
300571310 11 N/A Various Various 08/06/2024 4.42000 % 64,771.76 38,628.50 17,017,830.98 16,979,202.48 02/06/2025 0 0 0
304101390 12 N/A Various Various 08/06/2024 4.42000 % 50,091.49 25,668.57 13,160,806.73 13,135,138.16 06/06/2025 0 0 0
300571323 13 RT Port Charlotte FL 08/06/2024 4.58000 % 50,396.51 24,275.16 12,778,379.41 12,754,104.25 06/06/2025 0 0 0
304140014 14 RT Hagerstown MD 08/06/2024 3.99700 % 39,829.67 27,938.74 11,572,132.01 11,544,193.27 05/06/2025 0 0 0
304101380 15 N/A Various Various 08/06/2024 3.95000 % 34,595.41 24,721.74 10,170,966.22 10,146,244.48 05/06/2025 0 0 0
304101397 17 LO Omaha NE 08/06/2024 4.41000 % 36,164.10 19,987.30 9,523,132.93 9,503,145.63 06/06/2025 0 8 8
304140018 18 MF Tigard OR 08/06/2024 4.15400 % 35,512.57 16,525.39 9,927,877.55 9,911,352.16 03/06/2025 0 0 0
301461017 19 RT Temecula CA 08/06/2024 4.85000 % 37,081.29 16,215.58 8,878,791.86 8,862,576.28 05/06/2025 0 0 0
304140002 2 N/A Various Various 08/06/2024 3.90850 % 242,327.00 - 72,000,000.00 72,000,000.00 04/06/2025 0 0 0
304101399 20 SS Kaneohe HI 08/06/2024 3.93000 % 30,457.50 - 9,000,000.00 9,000,000.00 06/06/2025 0 0 0
304140021 21 MF Lafayette LA 08/06/2024 4.17300 % 27,255.45 16,614.38 7,584,828.50 7,568,214.12 05/06/2025 0 0 0
304101389 22 OF Coral Gables FL 08/06/2024 3.95000 % 24,967.87 17,740.48 7,340,492.62 7,322,752.14 06/06/2025 0 0 0
304101398 23 MF DeWitt MI 08/06/2024 4.38000 % 26,491.31 12,850.63 7,023,767.15 7,010,916.52 06/06/2025 0 0 0
304140024 24 RT Shippensburg PA 08/01/2024 4.30000 % 21,989.81 13,640.93 5,938,734.21 5,925,093.28 06/01/2025 0 0 0
304101391 25 RT Houston TX 08/06/2024 4.25000 % 21,567.95 11,023.07 5,893,328.57 5,882,305.50 06/06/2025 0 0 0
300571333 26 MF Deer Park TX 08/06/2024 4.31000 % 21,155.42 10,553.94 5,700,136.56 5,689,582.62 06/06/2025 0 0 0
304140027 27 MF Stillwater OK 08/06/2024 4.30000 % 20,243.13 10,933.77 5,467,012.49 5,456,078.72 05/06/2025 0 0 0
304140029 29 IN Doral FL 08/01/2024 4.28000 % 19,217.80 10,404.07 5,214,355.22 5,203,951.15 06/01/2025 0 0 0
304140003 3 MU Dallas TX 08/06/2024 4.09750 % 207,712.97 140,085.45 58,868,836.42 58,728,750.97 05/06/2025 0 0 0
304140030 30 MF Reno NV 08/06/2024 4.19050 % 19,731.18 9,088.13 5,467,993.05 5,458,904.92 11/06/2024 0 0 0
300571332 31 RT Overland Park KS 08/06/2024 4.49000 % 19,704.17 9,826.26 5,096,271.27 5,086,445.01 06/06/2025 0 0 0
300571331 32 N/A Various Various 08/06/2024 4.68000 % 19,532.68 9,055.68 4,846,820.09 4,837,764.41 03/06/2025 0 0 0
304140033 33 OF Troy MI 08/06/2024 4.69000 % 17,663.18 9,533.76 4,373,578.68 4,364,044.92 02/06/2025 0 0 0
304140034 34 RT North Smithfield RI 07/01/2024 4.14000 % 18,377.58 - 5,155,000.00 5,155,000.00 06/01/2025 B 13 0
304140035 35 N/A Various Various 08/06/2024 3.95700 % 15,765.11 7,981.87 4,626,705.46 4,618,723.59 06/06/2025 0 0 0
301461015 36 N/A Various Various 08/06/2024 4.39000 % 15,634.40 9,374.12 4,135,781.73 4,126,407.61 06/06/2025 0 0 0
300571328 37 RT Lakeland FL 08/06/2024 4.58000 % 16,079.02 8,982.02 4,076,946.53 4,067,964.51 03/06/2025 0 0 0
304140038 38 MF Kingsville TX 08/06/2024 4.30000 % 15,102.02 8,156.94 4,078,564.65 4,070,407.71 05/06/2025 0 0 0
304140039 39 RT Winston-Salem NC 08/06/2024 4.40000 % 14,170.11 8,514.36 3,739,912.29 3,731,397.93 05/06/2025 0 0 0
304101400 4 OF Pasadena CA 08/06/2024 4.13000 % 141,371.32 62,303.59 39,751,367.44 39,689,063.85 06/06/2025 0 0 0
Reports Available at sf.citidirect.com v. 21.09.28 Page 14 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
MORTGAGE LOAN DETAIL
August 12, 2024
Prop Paid Beginning Ending Payment Workout Mod
Type Through Gross Interest Principal Scheduled Scheduled Maturity Status Strategy Code
Loan ID OMCR (1) City State Date Coupon Payment Payment Balance Balance Date (2 ) (3 ) (4 )
304101396 40 RT Tallahassee FL 08/06/2024 4.40000 % 10,716.44 16,255.92 2,828,385.30 2,812,129.38 06/06/2025 0 0 0
304140041 41 MU Mesquite TX 08/01/2024 4.66000 % 13,052.92 7,080.30 3,252,839.62 3,245,759.32 06/01/2025 0 0 0
304101386 42 N/A Various Various 08/06/2024 4.15000 % 11,122.03 7,349.90 3,112,265.35 3,104,915.45 05/06/2025 0 0 0
304101387 43 OF Ann Arbor MI 08/06/2024 4.46000 % 12,608.60 5,924.84 3,283,015.21 3,277,090.37 06/06/2025 0 0 0
304140044 44 MF Cedar Rapids IA 08/06/2024 4.39000 % 11,858.09 6,148.04 3,136,829.44 3,130,681.40 06/06/2025 0 0 0
304140045 45 MF North Charleston SC 08/01/2024 4.72000 % 10,633.01 8,692.36 2,616,104.45 2,607,412.09 06/01/2025 0 0 0
304101407 46 LO Eagle CO 08/06/2024 4.31000 % 9,575.05 8,958.46 2,579,910.68 2,570,952.22 06/06/2025 0 0 0
300571326 47 SS Eustis FL 08/06/2024 4.48000 % 10,514.64 5,661.28 2,725,569.84 2,719,908.56 06/06/2025 0 0 0
304101388 49 RT Dover OH 08/06/2024 4.70000 % 8,364.10 4,498.12 2,066,627.36 2,062,129.24 05/06/2025 0 8 0
304140005 5 OF Oklahoma City OK 08/01/2024 3.93500 % 84,968.30 53,753.39 25,075,697.08 25,021,943.69 05/01/2025 0 0 0
300571324 50 SS Hammonton NJ 08/06/2024 4.77000 % 8,485.20 3,801.86 2,065,781.15 2,061,979.29 03/06/2025 0 0 0
304101392 6 N/A Various Various 08/06/2024 4.34000 % 98,251.70 48,429.09 26,290,033.76 26,241,604.67 06/06/2025 0 0 0
300571327 7 MF Pine Hill NJ 08/06/2024 4.41000 % 97,226.18 40,645.56 25,602,680.29 25,562,034.73 06/06/2025 0 0 0
304140008 8 MU Orinda CA 08/06/2024 4.27900 % 77,737.12 34,318.96 21,097,305.17 21,062,986.21 06/06/2025 0 0 0
304140009 9 MU Sugar Land TX 08/06/2024 4.10650 % 69,467.44 40,304.20 19,644,919.84 19,604,615.64 06/06/2025 0 0 0
Total Count = 47 1,934,114.72 872,446.71 635,988,315.16 635,115,868.45
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
NOI DETAIL
August 12, 2024
Property Ending Preceding Most Most Recent Most Recent
Type Scheduled Fiscal Recent Financial As of Financial Asof
Loan ID OMCR (1) City State Balance Year NOI NOI Start Date End Date
304101385 1 OF Chicago IL 100,000,000.00 (7,059,787.39 ) (3,341,055.14 ) 01/01/2024 06/30/2024
304140010 10 RT San Diego CA 22,200,000.00 2,859,973.00 569,209.51 01/01/2024 03/31/2024
300571310 11 N/A Various Various 16,979,202.48 1,812,117.00 421,531.00 Not Available Not Available
304101390 12 N/A Various Various 13,135,138.16 1,064,987.56 798,741.16 Not Available Not Available
300571323 13 RT Port Charlotte FL 12,754,104.25 1,026,395.06 878,629.53 Not Available Not Available
304140014 14 RT Hagerstown MD 11,544,193.27 1,241,288.31 520,955.39 01/01/2024 06/30/2024
304101380 15 N/A Various Various 10,146,244.48 1,837,735.84 1,025,962.01 Not Available Not Available
304101397 17 LO Omaha NE 9,503,145.63 1,075,109.03 1,088,395.78 04/01/2023 03/31/2024
304140018 18 MF Tigard OR 9,911,352.16 1,344,387.57 1,099,871.01 Not Available Not Available
301461017 19 RT Temecula CA 8,862,576.28 879,975.60 789,540.06 Not Available Not Available
304140002 2 N/A Various Various 72,000,000.00 33,508,489.00 7,659,069.51 01/01/2024 03/31/2024
304101399 20 SS Kaneohe HI 9,000,000.00 2,064,092.00 525,854.06 01/01/2024 03/31/2024
304140021 21 MF Lafayette LA 7,568,214.12 726,717.24 346,886.50 01/01/2024 06/30/2024
304101389 22 OF Coral Gables FL 7,322,752.14 956,722.97 823,015.32 01/01/2024 06/30/2024
304101398 23 MF DeWitt MI 7,010,916.52 903,337.00 692,632.00 Not Available Not Available
304140024 24 RT Shippensburg PA 5,925,093.28 992,856.81 272,425.33 01/01/2024 03/31/2024
304101391 25 RT Houston TX 5,882,305.50 799,377.90 186,729.55 01/01/2024 03/31/2024
300571333 26 MF Deer Park TX 5,689,582.62 920,794.87 516,487.94 01/01/2024 06/30/2024
304140027 27 MF Stillwater OK 5,456,078.72 308,477.00 185,554.00 Not Available Not Available
304140029 29 IN Doral FL 5,203,951.15 871,073.78 480,808.89 01/01/2024 06/30/2024
304140003 3 MU Dallas TX 58,728,750.97 36,106,650.00 33,049,289.00 09/01/2023 08/31/2024
304140030 30 MF Reno NV 5,458,904.92 1,026,033.00 232,917.00 Not Available Not Available
300571332 31 RT Overland Park KS 5,086,445.01 817,693.30 435,705.61 01/01/2024 06/30/2024
300571331 32 N/A Various Various 4,837,764.41 659,816.22 509,213.05 Not Available Not Available
304140033 33 OF Troy MI 4,364,044.92 986,802.00 663,457.00 Not Available Not Available
304140034 34 RT North Smithfield RI 5,155,000.00 401,800.00 200,900.00 01/01/2020 06/30/2020
304140035 35 N/A Various Various 4,618,723.59 1,153,945.06 257,246.19 01/01/2024 03/31/2024
301461015 36 N/A Various Various 4,126,407.61 525,700.09 137,835.53 Not Available Not Available
300571328 37 RT Lakeland FL 4,067,964.51 732,756.63 517,592.02 Not Available Not Available
304140038 38 MF Kingsville TX 4,070,407.71 542,292.69 428,143.00 Not Available Not Available
304140039 39 RT Winston-Salem NC 3,731,397.93 379,800.00 284,850.00 Not Available Not Available
304101400 4 OF Pasadena CA 39,689,063.85 3,278,036.56 2,509,614.30 Not Available Not Available
Reports Available at sf.citidirect.com v. 21.09.28 Page 16 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
NOI DETAIL
August 12, 2024
Property Ending Preceding Most Most Recent Most Recent
Type Scheduled Fiscal Recent Financial As of Financial Asof
Loan ID OMCR (1) City State Balance Year NOI NOI Start Date End Date
304101396 40 RT Tallahassee FL 2,812,129.38 423,466.98 187,757.56 Not Available Not Available
304140041 41 MU Mesquite TX 3,245,759.32 483,574.65 369,104.94 Not Available Not Available
304101386 42 N/A Various Various 3,104,915.45 411,049.13 200,429.55 01/01/2024 06/30/2024
304101387 43 OF Ann Arbor MI 3,277,090.37 478,709.88 96,913.75 01/01/2024 03/31/2024
304140044 44 MF Cedar Rapids IA 3,130,681.40 368,682.20 95,233.22 Not Available Not Available
304140045 45 MF North Charleston SC 2,607,412.09 482,814.00 264,209.00 Not Available Not Available
304101407 46 LO Eagle CO 2,570,952.22 428,154.00 394,103.00 Not Available Not Available
300571326 47 SS Eustis FL 2,719,908.56 412,024.72 166,368.14 01/01/2024 06/30/2024
304101388 49 RT Dover OH 2,062,129.24 369,632.97 81,018.00 Not Available Not Available
304140005 5 OF Oklahoma City OK 25,021,943.69 3,348,531.54 1,721,624.92 01/01/2024 06/30/2024
300571324 50 SS Hammonton NJ 2,061,979.29 308,914.00 92,220.09 Not Available Not Available
304101392 6 N/A Various Various 26,241,604.67 2,888,973.47 1,404,227.41 01/01/2024 06/30/2024
300571327 7 MF Pine Hill NJ 25,562,034.73 1,793,983.00 1,858,837.00 Not Available Not Available
304140008 8 MU Orinda CA 21,062,986.21 1,939,659.52 1,548,760.50 Not Available Not Available
304140009 9 MU Sugar Land TX 19,604,615.64 1,861,464.16 511,149.36 01/01/2024 03/31/2024
Total Count = 47 635,115,868.45 110,745,079.92 63,759,962.55
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
DELINQUENCY LOAN DETAIL
August 12, 2024
Actual Paid Current P&I Total P&I Cumulative Other Expense Payment Workout Most Recent
Principal Through Advances Advances Accrued Unpaid Advances Status Strategy Special Serv Foreclosure Bankruptcy REO
Loan ID OMCR Balance Date (Net of ASER) Outstanding Interest Advances Outstanding (2 ) (3 ) Transfer Date Date Date Date
304101385 1 100,000,000.00 10/06/2021 (430.56 ) 6,958,351.34 2,662,235.11 615,236.06 3 1 11/17/2021
304140034 34 5,155,000.00 07/01/2024 18,355.38 18,355.38 302.40 6,247.50 B 13 09/16/2020
Total Count = 2 105,155,000.00 17,924.82 6,976,706.72 2,662,537.51 621,483.56
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
COLLATERAL PERFORMANCE - DELINQUENCY AND LOAN STATUS DETAIL
August 12, 2024
Delinquent
(Does not include loans in Bankruptcy, Foreclosure, or REO)
30 Day 60 Day 90 Day 120 + Day Bankruptcy Foreclosure REO
Distribution
Date Count Balance Count Balance Count Balance Count Balance Count Balance Count Balance Count Balance
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
08/12/2024
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.7 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
07/12/2024
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.7 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
06/12/2024
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.7 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
05/10/2024
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.7 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
04/12/2024
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.7 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
03/12/2024
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.6 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
02/12/2024
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.6 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
01/12/2024
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.6 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
12/12/2023
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.6 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
11/10/2023
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.5 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
10/13/2023
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.5 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
0 0 0 0 0 0 1 100,000,000 0 0 0 0 0 0
09/12/2023
0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 2.1 % 15.5 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 % 0.0 %
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
APPRAISAL REDUCTION DETAIL
August 12, 2024
Beginning Ending Appraisal Appraisal Most Recent Cumulative
Loan ID OMCR Property Name Scheduled Balance Scheduled Balance Reduction Amount Reduction Date ASER Amount ASER Amount
304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 60,012,176.11 03/05/2024 - 1,102,148.51
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Citigroup Commercial Mortgage Trust 2015-GC31
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HISTORICAL APPRAISAL REDUCTION DETAIL
August 12, 2024
Distribution Beginning Ending Appraisal Appraisal Most Recent Cumulative
Date Loan ID OMCR Property Name Scheduled Balance Scheduled Balance Reduction Amount Reduction Date ASER Amount ASER Amount
8/12/2024 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 60,012,176.11 03/05/2024 - 1,102,148.51
7/12/2024 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 60,012,176.11 03/05/2024 - 1,102,148.51
6/12/2024 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 60,012,176.11 03/05/2024 - 1,102,148.51
5/10/2024 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 60,012,176.11 03/05/2024 - 1,102,148.51
4/12/2024 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 60,012,176.11 03/05/2024 - 1,102,148.51
3/12/2024 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 60,012,176.11 03/05/2024 159,048.94 1,102,148.51
2/12/2024 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 80,098.87 943,099.57
1/12/2024 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 80,098.87 863,000.70
12/12/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 77,515.03 782,901.83
11/10/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 80,098.87 705,386.80
10/13/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 77,515.03 625,287.93
9/12/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 80,098.87 547,772.90
8/11/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 80,098.87 467,674.03
7/12/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 77,515.03 387,575.16
6/12/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 80,098.87 310,060.13
5/12/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 77,515.03 229,961.26
4/13/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.53 03/01/2023 80,098.87 152,446.23
3/10/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 28,272,960.38 03/01/2023 72,347.36 72,347.36
2/10/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
1/12/2023 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
12/12/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
11/14/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
10/13/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
9/12/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
8/12/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
7/12/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
6/10/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
5/12/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
4/12/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
3/11/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
2/11/2022 304101385 1 135 South LaSalle 100,000,000.00 100,000,000.00 - 02/06/2022 - -
9/14/2020 304101397 17 Magnolia Hotel Omaha 10,410,719.56 10,445,039.27 - 08/06/2020 - -
8/12/2020 304101397 17 Magnolia Hotel Omaha 10,427,273.39 10,410,719.56 - 08/06/2020 - -
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Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
HISTORICAL APPRAISAL REDUCTION DETAIL
August 12, 2024
Distribution Beginning Ending Appraisal Appraisal Most Recent Cumulative
Date Loan ID OMCR Property Name Scheduled Balance Scheduled Balance Reduction Amount Reduction Date ASER Amount ASER Amount
9/12/2018 304140028 28 Infinity Corporate Center 5,924,901.16 - - - 41,157.18
8/10/2018 304140028 28 Infinity Corporate Center 5,933,247.11 5,924,901.16 2,799,940.38 08/06/2018 10,457.97 41,157.18
7/12/2018 304140028 28 Infinity Corporate Center 5,942,281.96 5,933,247.11 2,799,940.38 07/06/2018 10,120.62 30,699.21
6/12/2018 304140028 28 Infinity Corporate Center 5,950,562.60 5,942,281.96 2,799,940.38 06/06/2018 10,457.97 20,578.59
5/11/2018 304140028 28 Infinity Corporate Center 5,959,534.48 5,950,562.60 2,799,940.38 05/07/2018 10,120.62 10,120.62
Reports Available at sf.citidirect.com v. 21.09.28 Page 22 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
LOAN MODIFICATION DETAIL
August 12, 2024
Modification Modification
Loan ID OMCR Property Name Date Code (4)
304101397 17 Magnolia Hotel Omaha 07/01/2020 8
Reports Available at sf.citidirect.com v. 21.09.28 Page 23 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
HISTORICAL LOAN MODIFICATION DETAIL
August 12, 2024
Distribution Modification Modification
Date Loan ID OMCR Property Name Date Code (4)
08/12/2024 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
07/12/2024 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
06/12/2024 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
05/10/2024 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
04/12/2024 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
03/12/2024 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
02/12/2024 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
01/12/2024 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
12/12/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
11/10/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
10/13/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
09/12/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
08/11/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
07/12/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
06/12/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
05/12/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
04/13/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
03/10/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
02/10/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
01/12/2023 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
12/12/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
11/14/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
10/13/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
09/12/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
08/12/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
07/12/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
06/10/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
05/12/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
04/12/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
03/11/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
02/11/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
01/12/2022 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
12/10/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
Reports Available at sf.citidirect.com v. 21.09.28 Page 24 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
HISTORICAL LOAN MODIFICATION DETAIL
August 12, 2024
Distribution Modification Modification
Date Loan ID OMCR Property Name Date Code (4)
11/15/2021 304140016 16 Crowne Plaza Bloomington 05/06/2020 8
11/15/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
10/13/2021 304140016 16 Crowne Plaza Bloomington 05/06/2020 8
10/13/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
09/13/2021 304140016 16 Crowne Plaza Bloomington 05/06/2020 8
09/13/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
08/12/2021 304140016 16 Crowne Plaza Bloomington 05/06/2020 8
08/12/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
07/12/2021 304140016 16 Crowne Plaza Bloomington 05/06/2020 8
07/12/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
06/11/2021 304140016 16 Crowne Plaza Bloomington 05/06/2020 8
06/11/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
05/12/2021 304140016 16 Crowne Plaza Bloomington 05/06/2020 8
05/12/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
04/12/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
03/12/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
02/12/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
01/12/2021 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
12/11/2020 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
11/13/2020 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
10/13/2020 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
09/14/2020 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
08/12/2020 304101397 17 Magnolia Hotel Omaha 07/01/2020 8
Reports Available at sf.citidirect.com v. 21.09.28 Page 25 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
SPECIALLY SERVICED LOAN DETAIL
August 12, 2024
Special Servicing Ending Ending Most Most Recent Most Recent Most Recent
Workout Fee Amount Scheduled Actual Recent Valuation Special Servicer Master Servicer
Loan ID OMCR Strategy (3) Plus Adjustments Balance Balance Value Date Transfer Date Return Date
304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 67,700,000.00 01/08/2024 11/17/2021
304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
Total Count = 2 25,027.78 105,155,000.00 105,155,000.00 75,600,000.00
Reports Available at sf.citidirect.com v. 21.09.28 Page 26 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
HISTORICAL SPECIALLY SERVICED LOANS
August 12, 2024
Special Servicing Ending Ending Most Most Recent Most Recent Most Recent
Distribution Workout Fee Amount Scheduled Actual Recent Valuation Special Servicer Master Servicer
Date Loan ID OMCR Strategy (3) Plus Adjustments Balance Balance Value Date Transfer Date Return Date
08/12/2024 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 67,700,000.00 01/08/2024 11/17/2021
07/12/2024 304101385 1 1 20,833.33 100,000,000.00 100,000,000.00 67,700,000.00 01/08/2024 11/17/2021
06/12/2024 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 67,700,000.00 01/08/2024 11/17/2021
05/10/2024 304101385 1 1 20,833.33 100,000,000.00 100,000,000.00 67,700,000.00 01/08/2024 11/17/2021
04/12/2024 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 67,700,000.00 01/08/2024 11/17/2021
03/12/2024 304101385 1 1 20,138.89 100,000,000.00 100,000,000.00 67,700,000.00 01/08/2024 11/17/2021
02/12/2024 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
01/12/2024 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
12/12/2023 304101385 1 1 20,833.33 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
11/10/2023 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
10/13/2023 304101385 1 1 20,833.33 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
09/12/2023 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
08/11/2023 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
07/12/2023 304101385 1 1 20,833.33 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
06/12/2023 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
05/12/2023 304101385 1 1 20,833.33 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
04/13/2023 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
03/10/2023 304101385 1 1 19,444.44 100,000,000.00 100,000,000.00 90,000,000.00 01/01/2023 11/17/2021
02/10/2023 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
01/12/2023 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
12/12/2022 304101385 1 1 20,833.33 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
11/14/2022 304101385 1 1 21,527.78 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
10/13/2022 304101385 1 10 20,833.33 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
09/12/2022 304101385 1 10 21,527.78 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
08/12/2022 304101385 1 10 21,527.78 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
07/12/2022 304101385 1 10 20,833.33 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
06/10/2022 304101385 1 10 21,527.78 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
05/12/2022 304101385 1 10 20,833.33 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
04/12/2022 304101385 1 10 21,527.78 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
03/11/2022 304101385 1 10 19,444.44 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
02/11/2022 304101385 1 13 21,527.78 100,000,000.00 100,000,000.00 130,000,000.00 01/01/2022 11/17/2021
01/12/2022 304101385 1 13 21,527.78 100,000,000.00 100,000,000.00 330,000,000.00 03/30/2015 11/17/2021
Reports Available at sf.citidirect.com v. 21.09.28 Page 27 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
HISTORICAL SPECIALLY SERVICED LOANS
August 12, 2024
Special Servicing Ending Ending Most Most Recent Most Recent Most Recent
Distribution Workout Fee Amount Scheduled Actual Recent Valuation Special Servicer Master Servicer
Date Loan ID OMCR Strategy (3) Plus Adjustments Balance Balance Value Date Transfer Date Return Date
12/10/2021 304101385 1 13 8,333.33 100,000,000.00 100,000,000.00 330,000,000.00 03/30/2015 11/17/2021
05/11/2018 304101388 49 8 (22,983.33 ) 2,364,016.73 2,364,016.73 3,825,000.00 04/01/2015 04/25/2018
04/12/2018 304101388 49 9 3,500.00 2,367,605.83 2,367,605.83 3,825,000.00 04/01/2015 09/19/2017
03/12/2018 304101388 49 13 3,500.00 2,370,872.60 2,378,289.43 3,825,000.00 04/01/2015 09/19/2017
02/12/2018 304101388 49 13 3,500.00 2,375,052.68 2,378,289.43 3,825,000.00 04/01/2015 09/19/2017
01/12/2018 304101388 49 13 3,500.00 2,378,289.43 2,378,289.43 3,825,000.00 04/01/2015 09/19/2017
12/12/2017 304101388 49 13 3,500.00 2,381,513.14 2,385,033.98 3,825,000.00 04/01/2015 09/19/2017
11/10/2017 304101388 49 13 3,500.00 2,385,033.98 2,391,725.13 3,825,000.00 04/01/2015 09/19/2017
10/13/2017 304101388 49 13 1,983.33 2,388,230.50 2,391,725.13 3,825,000.00 04/01/2015 09/19/2017
10/13/2020 304101397 17 8 - 10,445,039.27 10,445,039.27 13,000,000.00 04/20/2020 04/06/2020 09/02/2020
09/14/2020 304101397 17 1 3,500.00 10,445,039.27 10,445,039.27 13,000,000.00 04/20/2020 04/06/2020
08/12/2020 304101397 17 1 3,500.00 10,410,719.56 10,445,039.27 13,000,000.00 04/20/2020 04/06/2020
07/10/2020 304101397 17 98 3,500.00 10,427,273.39 10,445,039.27 16,600,000.00 04/01/2015 04/06/2020
06/12/2020 304101397 17 98 3,500.00 10,445,039.27 10,445,039.27 16,600,000.00 04/01/2015 04/06/2020
05/12/2020 304101397 17 13 3,500.00 10,461,463.26 10,461,463.26 16,600,000.00 04/01/2015 04/06/2020
04/10/2020 304101397 17 13 - 10,479,103.95 10,495,399.07 16,600,000.00 04/01/2015 04/06/2020
11/15/2021 304140016 16 6 (25,040.30 ) - - 31,900,000.00 12/01/2014 02/04/2021
10/13/2021 304140016 16 6 2,262.80 10,840,353.25 10,840,353.25 31,900,000.00 12/01/2014 02/04/2021
09/13/2021 304140016 16 6 2,342.44 10,861,430.72 10,881,026.79 31,900,000.00 12/01/2014 02/04/2021
08/12/2021 304140016 16 6 2,346.65 10,881,026.79 10,921,389.82 31,900,000.00 12/01/2014 02/04/2021
07/12/2021 304140016 16 2 2,275.29 10,900,544.70 10,921,389.82 31,900,000.00 12/01/2014 02/04/2021
06/11/2021 304140016 16 2 2,355.30 10,921,389.82 10,940,746.76 31,900,000.00 12/01/2014 02/04/2021
05/12/2021 304140016 16 2 2,283.63 10,940,746.76 11,004,001.62 31,900,000.00 12/01/2014 02/04/2021
04/12/2021 304140016 16 2 2,363.89 10,961,436.70 11,004,001.62 31,900,000.00 12/01/2014 02/04/2021
03/12/2021 304140016 16 6 2,139.67 10,980,633.92 11,004,001.62 31,900,000.00 12/01/2014 02/04/2021
02/12/2021 304140016 16 6 2,373.01 11,004,001.62 11,041,980.66 31,900,000.00 12/01/2014 02/04/2021
01/12/2021 304140016 16 6 2,377.09 11,023,029.08 11,041,980.66 31,900,000.00 12/01/2014 11/06/2020
12/11/2020 304140016 16 98 1,920.53 11,041,980.66 11,062,279.84 31,900,000.00 12/01/2014 11/06/2020
09/12/2018 304140028 28 8 - - - 3,875,000.00 10/12/2017 09/19/2017
08/10/2018 304140028 28 2 3,500.00 5,924,901.16 5,986,255.08 3,875,000.00 10/12/2017 09/19/2017
07/12/2018 304140028 28 2 3,500.00 5,933,247.11 5,986,255.08 3,875,000.00 10/12/2017 09/19/2017
06/12/2018 304140028 28 2 3,500.00 5,942,281.96 5,986,255.08 3,875,000.00 10/12/2017 09/19/2017
Reports Available at sf.citidirect.com v. 21.09.28 Page 28 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
HISTORICAL SPECIALLY SERVICED LOANS
August 12, 2024
Special Servicing Ending Ending Most Most Recent Most Recent Most Recent
Distribution Workout Fee Amount Scheduled Actual Recent Valuation Special Servicer Master Servicer
Date Loan ID OMCR Strategy (3) Plus Adjustments Balance Balance Value Date Transfer Date Return Date
05/11/2018 304140028 28 2 3,500.00 5,950,562.60 5,986,255.08 8,500,000.00 03/12/2015 09/19/2017
04/12/2018 304140028 28 2 3,500.00 5,959,534.48 5,986,255.08 8,500,000.00 03/12/2015 09/19/2017
03/12/2018 304140028 28 2 3,500.00 5,967,750.30 5,986,255.08 8,500,000.00 03/12/2015 09/19/2017
02/12/2018 304140028 28 2 3,500.00 5,978,109.06 5,994,370.49 8,500,000.00 03/12/2015 09/19/2017
01/12/2018 304140028 28 2 3,500.00 5,986,255.08 5,994,370.49 8,500,000.00 03/12/2015 09/19/2017
12/12/2017 304140028 28 2 3,500.00 5,994,370.49 6,003,183.05 8,500,000.00 03/12/2015 09/19/2017
11/10/2017 304140028 28 2 3,500.00 6,003,183.05 6,011,234.86 8,500,000.00 03/12/2015 09/19/2017
10/13/2017 304140028 28 13 1,983.33 6,011,234.86 6,019,986.09 8,500,000.00 03/12/2015 09/19/2017
08/12/2024 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
07/12/2024 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
06/12/2024 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
05/10/2024 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
04/12/2024 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
03/12/2024 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
02/12/2024 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
01/12/2024 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
12/12/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
11/10/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
10/13/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
09/12/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
08/11/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
07/12/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
06/12/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
05/12/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
04/13/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
03/10/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
02/10/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
01/12/2023 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
12/12/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
11/14/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
10/13/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
09/12/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
Reports Available at sf.citidirect.com v. 21.09.28 Page 29 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
HISTORICAL SPECIALLY SERVICED LOANS
August 12, 2024
Special Servicing Ending Ending Most Most Recent Most Recent Most Recent
Distribution Workout Fee Amount Scheduled Actual Recent Valuation Special Servicer Master Servicer
Date Loan ID OMCR Strategy (3) Plus Adjustments Balance Balance Value Date Transfer Date Return Date
08/12/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
07/12/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
06/10/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
05/12/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
04/12/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
03/11/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
02/11/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
01/12/2022 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
12/10/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
11/15/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
10/13/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
09/13/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
08/12/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
07/12/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
06/11/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
05/12/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
04/12/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
03/12/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
02/12/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
01/12/2021 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
12/11/2020 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
11/13/2020 304140034 34 13 3,500.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
10/13/2020 304140034 34 13 1,750.00 5,155,000.00 5,155,000.00 7,900,000.00 03/08/2015 09/16/2020
Reports Available at sf.citidirect.com v. 21.09.28 Page 30 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
UNSCHEDULED PRINCIPAL DETAIL
August 12, 2024
Liquidation / Liquid / Prepay Principal Principal Prepayment Interest Prepayment Yield Maintenance
Loan ID OMCR Prepayment Date Code (5) Collections Adjustments Excess / (Shortfall) Penalties (PPP) Penalties (YM)
No Loans with Unscheduled Principal Activity to Report.
Reports Available at sf.citidirect.com v. 21.09.28 Page 31 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31
HISTORICAL UNSCHEDULED PRINCIPAL DETAIL
August 12, 2024
Prepayment Yield Maintenance
(PPP) Penalties (YM)
Distribution Liquidation / Liquid / Prepay Principal Principal Prepayment Interest
Date Loan ID OMCR Prepayment Date Code (5) Collections Adjustments Excess / (Shortfall) Penalties
5/12/2022 304101397 17 08/06/2021 1 218,224.17 - - - -
11/15/2021 304140016 16 10/15/2021 9 10,820,594.32 - - - 1,973,242.03
9/13/2021 304101372 48 08/27/2021 9 2,333,597.23 - - - 72,353.89
9/14/2020 304101397 17 0 (34,319.71 ) - - - -
9/12/2018 304140028 28 08/28/2018 3 4,822,832.84 1,093,690.89 - - -
Reports Available at sf.citidirect.com v. 21.09.28 Page 32 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31 August 12, 2024
LIQUIDATED LOAN DETAIL
Beginning Most Liquidation Net Net Realized Date of Loss with
Scheduled Recent Sales Proceeds Liquidation Proceeds Loss to Current Current Cumulative Cumulative
Loan ID OMCR Balance Value Price Received Expense Available Trust Adj. to Loan Adj. to Loan Adj. to Loan Adj. to Trust
No Loans liquidated to Report.
Reports Available at sf.citidirect.com v. 21.09.28 Page 33 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31 August 12, 2024
HISTORICAL LIQUIDATED LOAN
Beginning Most Liquidation Net Net Realized Date of Loss with
Distribution Scheduled Recent Sales Proceeds Liquidation Proceeds Loss to Current Current Cumulative Cumulative
Date Loan ID OMCR Balance Value Price Received Expense Available Trust Adj. to Loan Adj. to Loan Adj. to Loan Adj. to Trust
04/13/2023 304140016 16 - - - - - - - 600.00 - -
08/12/2022 304140028 28 - - - - - - (57,026.11 ) - - (57,026.11 )
11/15/2021 304140016 16 10,840,353.25 31,900,000.00 - 13,078,247.35 2,237,894.10 10,840,353.25 - - - -
09/12/2018 304140028 28 5,924,901.16 3,875,000.00 - 5,400,800.31 569,590.04 4,831,210.27 1,093,690.89 - - 1,093,690.89
Reports Available at sf.citidirect.com v. 21.09.28 Page 34 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31 August 12, 2024
CREFC® INVESTOR REPORTING PACKAGE LEGENDS
1|CREFC Investor Reporting Package Legends
Property Type (1) Workout Strategy (3) Liquidation/Prepayment Code (5)
MF Multifamily 1 Modification 1 Partial Liquidation (Curtailment)
RT Retail 2 Foreclosure 2 Payoff Prior To Maturity
HC HealthCare 3 Bankruptcy 3 Disposition / Liquidation
IN Industrial 4 Extension 4 Repurchase / Substitution
MH Mobile Home Park 5 Note Sale 5 Full Payoff At Maturity
OF Office 6 DPO 6 DPO
MU Mixed Use 7 REO 7 Liquidation prior to 7/1/2006
LO Lodging 8 Resolved 8 Payoff With Penalty
SS Self Storage 9 Pending Return to Master Servicer 9 Payoff With Yield Maintenance
SE Securities 10 Deed In Lieu of Foreclosure 10 Curtailment With Penalty
CH Cooperative Housing 11 Full Payoff 11 Curtailment With Yield Maintenance
ZZ Missing Information 12 Reps and Warranties
SF SF 13 TBD
WH Warehouse 98 Other
OT Other
Modification Code (4)
Payment Status of Loan (2)
1 Maturity Date Extension
A In Grace Period 2 Amortization Change
B Late, but less than 30 Days 3 Principal Write-Off
0 Current 4 Blank (formerly Combination)
1 30-59 Days Delinquent 5 Temporary Rate Reduction
2 60-89 Days Delinquent 6 Capitalization of Interest
3 90-120 Days Delinquent 7 Capitalization of Taxes
4 Performing Matured Balloon 8 Other
5 Non Performing Matured Balloon 9 Combination
6 121+ Days Delinquent 10 Forbearance
Reports Available at sf.citidirect.com v. 21.09.28 Page 35 of 36 © Copyright 2024 Citigroup

Citigroup Commercial Mortgage Trust 2015-GC31
Commercial Mortgage Pass-Through Certificates, Series 2015-GC31 August 12, 2024
NOTES
No Notes available for this deal at this time.
Reports Available at sf.citidirect.com v. 21.09.28 Page 36 of 36 © Copyright 2024 Citigroup