Exhibit 99.1

Navient Student Loan Trust 2015-1

Monthly Servicing Report

Distribution Date 09/25/2025

Collection Period 08/01/2025 - 08/31/2025

Navient Funding, LLC - Depositor

Navient Solutions -  Master Servicer and Administrator

Wells Fargo - Indenture Trustee

Wells Fargo Bank, National Association - Eligible Lender Trustee

Navient Funding - Excess Distribution Certificateholder

Page 1 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025

I.
Deal Parameters

A
Student Loan Portfolio Characteristics
 
02/26/2015
   
07/31/2025
   
08/31/2025
 

Principal Balance
 
$
968,675,662.97
   
$
275,204,417.08
   
$
273,462,582.55
 

Interest to be Capitalized Balance    
8,452,423.99
     
2,767,483.65
     
2,835,971.54
 

Pool Balance
 
$
977,128,086.96
   
$
277,971,900.73
   
$
276,298,554.09
 

Specified Reserve Account Balance
   
16,379,916.00
     
- N/A -
     
- N/A -
 

Adjusted Pool (1)
 
$
993,508,002.96
   
$
277,971,900.73
   
$
276,298,554.09
 

Weighted Average Coupon (WAC)
   
6.11%

   
6.62%

   
6.62%


Number of Loans    
155,605
     
29,050
     
28,709
 

Aggregate Outstanding Principal Balance - Tbill          
$
36,310,143.53
   
$
36,113,528.59
 

Aggregate Outstanding Principal Balance - SOFR          
$
241,661,757.20
   
$
240,185,025.50
 

Pool Factor            
0.280009761
     
0.278324147
 

Since Issued Constant Prepayment Rate            
(3.54)%

   
(3.56)%


(1)
The Specified Reserve Account balance is included in the Adjusted Pool until the Pool Balance is less than or equal to 40% of the original pool.

B
Debt Securities
 
Cusip/Isin
 
08/25/2025
   
09/25/2025
 
 
A2
 
63939FAB6
 
$
247,102,322.22
    $
245,454,075.78
 
 
B
 
63939FAC4
 
$
26,700,000.00
   
$
26,700,000.00
 

C
Account Balances
 
08/25/2025
   
09/25/2025
 
 
Reserve Account Balance
 
$
992,722.00
   
$
992,722.00
 
 
Capitalized Interest Account Balance
   
-
     
-
 
 
Floor Income Rebate Account
 
$
170,750.44
   
$
54,376.60
 
 
Supplemental Loan Purchase Account
   
-
     
-
 

D
Asset / Liability
 
08/25/2025
   
09/25/2025
 
 
Adjusted Pool Balance + Supplemental Loan Purchase
 
$
277,971,900.73
   
$
276,298,554.09
 
 
Total Notes
 
$
273,802,322.22
   
$
272,154,075.78
 
 
Difference
 
$
4,169,578.51
   
$
4,144,478.31
 
 
Parity Ratio
   
1.01523
     
1.01523
 

Page 2 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025

II.
Trust Activity 08/01/2025 through 08/31/2025

A
Student Loan Principal Receipts
     
 
Borrower Principal
   
647,464.49
 
 
Guarantor Principal
   
1,016,406.00
 
 
Consolidation Activity Principal
   
899,977.79
 
 
Seller Principal Reimbursement
   
-
 
 
Servicer Principal Reimbursement
   
-
 
 
Rejected Claim Repurchased Principal
   
-
 
 
Other Principal Deposits
   
-
 
 
Total Principal Receipts
 
$
2,563,848.28
 
B
Student Loan Interest Receipts
       
 
Borrower Interest
   
315,542.13
 
 
Guarantor Interest
   
42,917.22
 
 
Consolidation Activity Interest
   
76,402.03
 
 
Special Allowance Payments
   
458,839.60
 
 
Interest Subsidy Payments
   
150,572.94
 
 
Seller Interest Reimbursement
   
0.00
 
 
Servicer Interest Reimbursement
   
0.00
 
 
Rejected Claim Repurchased Interest
   
0.00
 
 
Other Interest Deposits
   
19,965.79
 
 
Total Interest Receipts
 
$
1,064,239.71
 
C
Reserves in Excess of Requirement
 

-
 
D
Investment Income
 
$
14,953.00
 
E
Funds Borrowed from Next Collection Period
   
-
 
F
Funds Repaid from Prior Collection Period
   
-
 
G
Loan Sale or Purchase Proceeds
   
-
 
H
Initial Deposits to Collection Account
   
-
 
I
Excess Transferred from Other Accounts
  $
170,750.44
 
J
Other Deposits
   
-
 
K
Funds Released from Capitalized Interest Account
   
-
 
L
Less:  Funds Previously Remitted:
       
 
Servicing Fees to Servicer
   
-
 
 
Consolidation Loan Rebate Fees to Dept. of Education
 
$
(100,798.87)
 
 
Floor Income Rebate Fees to Dept. of Education
  $
(172,045.95)
 
 
Funds Allocated to the Floor Income Rebate Account
 
$
(54,376.60)
 
M
AVAILABLE FUNDS
 
$
3,486,570.01
 
N
Non-Cash Principal Activity During Collection Period
 
$
(822,013.75)
 
O
Non-Reimbursable Losses During Collection Period
 
$
26,295.87
 
P
Aggregate Purchased Amounts by the Depositor, Servicer or Seller
 

-
 
Q
Aggregate Loan Substitutions
   
-
 

Page 3 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025

III.
2015-1 Portfolio Characteristics

       
08/31/2025
   
07/31/2025
 
        
Wtd Avg
Coupon
   
# Loans
   
Principal
 
% of
Principal
   
Wtd Avg
Coupon
   
# Loans
   
Principal
 
% of
Principal
 
INTERIM:
 
IN SCHOOL
   
6.79%

   
22
   
$
115,232.69
   
0.042%

   
6.79%

   
22
   
$
115,232.69
   
0.042%


 
GRACE
   
6.80%

   
2
   
$
1,823.00
   
0.001%

   
6.80%

   
2
   
$
1,823.00
   
0.001%


  DEFERMENT
   
6.53%

   
1,599
   
$
13,616,162.55
   
4.979%

   
6.56%

   
1,687
   
$
14,149,999.86
   
5.142%

                                                                 
REPAYMENT:
 
CURRENT
   
6.55%

   
17,459
   
$
159,699,888.90
   
58.399%

   
6.56%

   
17,620
   
$
158,966,342.49
   
57.763%


  31-60 DAYS DELINQUENT
   
6.69%

   
1,329
   
$
13,558,490.37
   
4.958%

   
6.64%

   
1,359
   
$
15,473,896.01
   
5.623%


  61-90 DAYS DELINQUENT    
6.61%

   
878
   
$
9,690,576.44
   
3.544%

   
6.75%


 
806
   
$
7,906,511.02
   
2.873%


  91-120 DAYS DELINQUENT    
6.68%

   
576
   
$
5,767,227.38
   
2.109%

   
6.73%

   
649
   
$
6,343,838.27
   
2.305%


  > 120 DAYS DELINQUENT    
6.60%

   
2,278
   
$
23,081,671.52
   
8.441%

   
6.56%

   
2,223
   
$
23,112,646.19
   
8.398%

                                                                 

  FORBEARANCE    
6.85%

   
4,304
   
$
45,326,439.33
   
16.575%

   
6.80%

   
4,398
   
$
46,968,836.09
   
17.067%


  CLAIMS IN PROCESS    
6.40%

   
262
   
$
2,605,070.37
   
0.953%

   
6.53%

   
284
   
$
2,165,291.46
   
0.787%

                                                                 
TOTAL
                28,709
   
$
273,462,582.55
    100.00%

            29,050
   
$
275,204,417.08
    100.00%


*
Percentages may not total 100% due to rounding

Page 4 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025

IV.
2015-1 Portfolio Characteristics (cont'd)

   
08/31/2025
   
07/31/2025
 
Pool Balance
 
$
276,298,554.09
   
$
277,971,900.73
 
Outstanding Borrower Accrued Interest
 
$
13,150,113.61
   
$
12,950,891.83
 
Borrower Accrued Interest to be Capitalized
 
$
2,835,971.54
   
$
2,767,483.65
 
Borrower Accrued Interest >30 Days Delinquent
 
$
2,101,800.66
   
$
2,026,303.06
 
Total # Loans
   
28,709
     
29,050
 
Total # Borrowers
   
12,518
     
12,658
 
Weighted Average Coupon
   
6.62%

   
6.62%

Weighted Average Remaining Term
   
202.08
     
201.10
 
Non-Reimbursable Losses
 
$
26,295.87
   
$
31,246.43
 
Cumulative Non-Reimbursable Losses
 
$
5,699,263.77
   
$
5,672,967.90
 
Since Issued Constant Prepayment Rate (CPR)
   
-3.56%

   
-3.54%

Loan Substitutions
   
-
     
-
 
Cumulative Loan Substitutions
   
-
     
-
 
Rejected Claim Repurchases
   
-
     
-
 
Cumulative Rejected Claim Repurchases
 
$
405,329.34
   
$
405,329.34
 
Unpaid Primary Servicing Fees
   
-
     
-
 
Unpaid Administration Fees
   
-
     
-
 
Unpaid Carryover Servicing Fees
   
-
     
-
 
Note Principal Shortfall
   
-
     
-
 
Note Interest Shortfall
   
-
     
-
 
Unpaid Interest Carryover
   
-
     
-
 
Non-Cash Principal Activity - Capitalized Interest
 
$
848,599.74
   
$
1,074,318.12
 
Borrower Interest Accrued
 
$
1,482,590.00
   
$
1,491,660.81
 
Interest Subsidy Payments Accrued
 
$
48,409.08
   
$
49,385.15
 
Special Allowance Payments Accrued
 
$
157,640.19
   
$
159,411.06
 

Page 5 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025

V.
2015-1 Portfolio Statistics by School and Program

A
LOAN TYPE
 
Weighted
Average Coupon
   
# LOANS
   
$ AMOUNT
     
% *
 
 
- GSL (1) - Subsidized
   
6.68%

   
12,838
     
63,754,288.70
     
23.314%

 
- GSL - Unsubsidized
   
6.79%

   
10,938
     
88,612,563.22
     
32.404%

 
- PLUS (2) Loans
   
8.33%

   
401
     
8,546,656.52
     
3.125%

 
- SLS (3) Loans
   
7.26%

   
39
     
328,541.84
     
0.120%

 
- Consolidation Loans
   
6.31%

   
4,493
     
112,220,532.27
     
41.037%

 
Total
   
6.62%

   
28,709
   
$
273,462,582.55
     
100.000%


B
SCHOOL TYPE
 
Weighted
Average Coupon
   
# LOANS
   
$ AMOUNT
     
% *
 
 
- Four Year
   
6.84%

   
19,506
     
137,226,907.92
     
50.181%

 
- Two Year
   
6.77%

   
3,725
     
18,739,442.99
     
6.853%

 
- Technical
   
6.79%

   
985
     
5,273,302.26
     
1.928%

 
- Other
   
6.31%

   
4,493
     
112,222,929.38
     
41.038%

 
Total
   
6.62%

   
28,709
   
$
273,462,582.55
     
100.000%


*
Percentages may not total 100% due to rounding.

(1)
Guaranteed Stafford Loan

(2)
Parent Loans for Undergraduate Students

(3)
Supplemental Loans to Students.  The Unsubsidized Stafford Loan program replaced the SLS program on July 1, 1994.

Page 6 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025

VI.
2015-1 Waterfall for Distributions

     
Paid
   
Remaining
Funds Balance
 
Total Available Funds
       
$
3,486,570.01
 
A
Trustee Fees
   
-
   
$
3,486,570.01
 
B
Primary Servicing Fee
 
$
59,832.02
   
$
3,426,737.99
 
C
Administration Fee
 
$
6,667.00
   
$
3,420,070.99
 
D
Class A Noteholders' Interest Distribution Amount
 
$
1,077,290.42
   
$
2,342,780.57
 
E
Class B Noteholders' Interest Distribution Amount
 
$
137,096.32
   
$
2,205,684.25
 
F
Reserve Account Reinstatement
   
-
   
$
2,205,684.25
 
G
Class A Noteholders' Principal Distribution Amount
 
$
1,648,246.44
   
$
557,437.81
 
H
Class B Noteholders' Principal Distribution Amount
   
-
   
$
557,437.81
 
I
Unpaid Expenses of The Trustees
   
-
   
$
557,437.81
 
J
Carryover Servicing Fee
   
-
   
$
557,437.81
 
K
Remaining Amounts to the Noteholders after the first auction date
   
-
   
$
557,437.81
 
L
Excess Distribution Certificateholder
 
$
557,437.81
     
-
 

Waterfall Triggers
     
A
Student Loan Principal Outstanding
 
$
273,462,582.55
 
B
Interest to be Capitalized
 
$
2,835,971.54
 
C
Capitalized Interest Account Balance
   
-
 
D
Reserve Account Balance (after any reinstatement)
 
$
992,722.00
 
E
Less:  Specified Reserve Account Balance
 
$
(992,722.00)

F
Total
 
$
276,298,554.09
 
G
Class A Notes Outstanding (after application of available funds)
 
$
245,454,075.78
 
H
Insolvency Event or Event of Default Under Indenture
    N

I
Available Funds Applied to Class A Noteholders’ Distribution Amount Before Any Amounts are Applied to the Class B Noteholders’ Distribution Amount (G>F or H=Y)
    N


Page 7 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025

VII.
2015-1 Distributions

Distribution Amounts

     
A2
      B

Cusip/Isin
 
63939FAB6
   
63939FAC4
 
Beginning Balance
 
$
247,102,322.22
   
$
26,700,000.00
 
Index
 
SOFR
   
SOFR
 
Spread/Fixed Rate
   
0.60%

   
1.50%

Record Date (Days Prior to Distribution)
 
1 NEW YORK BUSINESS DAY
   
1 NEW YORK BUSINESS DAY
 
Accrual Period Begin
 
8/25/2025
   
8/25/2025
 
Accrual Period End
 
9/25/2025
   
9/25/2025
 
Daycount Fraction
   
0.08611111
     
0.08611111
 
Interest Rate*
    5.06287%

   
5.96287%

Accrued Interest Factor
   
0.004359694
     
0.005134694
 
Current Interest Due
 
$
1,077,290.42
   
$
137,096.32
 
Interest Shortfall from Prior Period Plus Accrued Interest
   
-
     
-
 
Total Interest Due
 
$
1,077,290.42
   
$
137,096.32
 
Interest Paid
 
$
1,077,290.42
   
$
137,096.32
 
Interest Shortfall
   
-
     
-
 
Principal Paid
 
$
1,648,246.44
   
-
 
Ending Principal Balance
 
$
245,454,075.78
   
$
26,700,000.00
 
Paydown Factor
   
0.002617511
     
0.000000000
 
Ending Balance Factor
   
0.389795261
     
1.000000000
 

*
Pay rates for Current Distribution.  For the interest rates applicable to the next distribution date, please see https://images.navient.com/investors/data/abrate.txt.

Page 8 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025

VIII.
2015-1 Reconciliations

A
Principal Distribution Reconciliation
     
 
Notes Outstanding Principal Balance
 
$
273,802,322.22
 
 
Adjusted Pool Balance
 
$
276,298,554.09
 
 
Overcollateralization Amount
 
$
4,144,478.31
 
 
Principal Distribution Amount
 
$
1,648,246.44
 
 
Principal Distribution Amount Paid
 
$
1,648,246.44
 
            
B
Reserve Account Reconciliation
       
 
Beginning Period Balance
 
$
992,722.00
 
 
Reserve Funds Utilized
   
0.00
 
 
Reserve Funds Reinstated
   
0.00
 
 
Balance Available
 
$
992,722.00
 
 
Required Reserve Acct Balance
 
$
992,722.00
 
 
Release to Collection Account
 

-
 
 
Ending Reserve Account Balance
 
$
992,722.00
 
            
C
Floor Income Rebate Account
       
 
Beginning Period Balance
 
$
170,750.44
 
 
Deposits for the Period
 
$
54,376.60
 
 
Release to Collection Account
  $
(170,750.44)
 
 
Ending Balance
 
$
54,376.60
 
            
D
Supplemental Purchase Account
       
 
Beginning Period Balance
   
-
 
 
Supplemental Loan Purchases
   
-
 
 
Transfers to Collection Account
   
-
 
 
Ending Balance
   
-
 


Page 9 of 9
Trust 2015-1 Monthly Servicing Report: Collection Period 08/01/2025 - 08/31/2025, Distribution Date 09/25/2025