Exhibit 99.1
MONTHLY SERVICER'S CERTIFICATE
CARMAX BUSINESS SERVICES, LLC
CARMAX AUTO OWNER TRUST
SERIES 2023-4
Collection Period09/01/26-09/30/26
Determination Date10/9/2026
Distribution Date10/15/2026
Additional information, including defined terms, can be found in the prospectus on the SEC's EDGAR system (http://www.sec.gov) under File No. 333-260819-08.




Pool Balance
1.Pool Balance on the close of the last day of the preceding Collection Period$371,582,358.88 
2.Collections allocable to Principal$18,851,400.11 
3.Purchase Amount allocable to Principal$0.00 
4.Defaulted Receivables$1,712,913.95 
5.Pool Balance on the close of the last day of the related Collection Period$351,018,044.82 
(Ln1 - Ln2 - Ln3 - Ln4)
6.Total number of Receivables outstanding on the close of the last day of the related Collection Period30,947 
7.Initial Pool Balance$1,518,987,901.90 
Beginning of PeriodEnd of Period
8.Note Balances
a. Class A-1 Note Balance
$0.00 $0.00 
b. Class A-2a Note Balance$0.00 $0.00 
c. Class A-2b Floating Rate Note Balance$0.00 $0.00 
d. Class A-3 Note Balance$138,095,010.11 $117,530,696.05 
e. Class A-4 Note Balance$90,700,000.00 $90,700,000.00 
f. Class B Note Balance$44,810,000.00 $44,810,000.00 
g. Class C Note Balance$42,530,000.00 $42,530,000.00 
h. Class D Note Balance$36,460,000.00 $36,460,000.00 
i. Note Balance (sum a - h)$352,595,010.11 $332,030,696.05 
9.Pool Factors
a. Class A-1 Note Pool Factor0.0000000 0.0000000 
b. Class A-2a Note Pool Factor0.0000000 0.0000000 
c. Class A-2b Floating Rate Note Pool Factor0.0000000 0.0000000 
d. Class A-3 Note Pool Factor0.2876979 0.2448556 
e. Class A-4 Note Pool Factor1.0000000 1.0000000 
f. Class B Note Pool Factor1.0000000 1.0000000 
g. Class C Note Pool Factor1.0000000 1.0000000 
h. Class D Note Pool Factor1.0000000 1.0000000 
i. Note Pool Factor0.2350633 0.2213538 
10.Overcollateralization Target Amount$18,987,348.77 
11.Current overcollateralization amount (Pool Balance - Note Balance)$18,987,348.77 
12.Weighted Average Coupon11.39 %
13.Weighted Average Original Termmonths66.57 
14.Weighted Average Remaining Termmonths27.59 
15.30 day Average SOFR for the accrual period ending 10/14/20263.64850 %
16.Note Rate applicable to the Class A-2b notes for the interest period ending 10/14/2026N/A
Collections
17.Finance Charges:
a. Collections allocable to Finance Charge$3,479,303.55 
b. Liquidation Proceeds allocable to Finance Charge$8,314.54 
c. Purchase Amount allocable to Finance Charge$0.00 
d. Available Finance Charge Collections (sum a - c)$3,487,618.09 
18.Principal:
a. Collections allocable to Principal$18,851,400.11 
b. Liquidation Proceeds allocable to Principal$1,052,151.70 
c. Purchase Amount allocable to Principal$0.00 
d. Available Principal Collections (sum a - c)$19,903,551.81 
19.Total Finance Charge and Principal Collections (17d + 18d)$23,391,169.90 
20.Interest Income from Collection Account$61,756.27 
21.Simple Interest Advances$0.00 
22.Available Collections (Ln19 + 20 + 21)$23,452,926.17 



Available Funds
23.Available Collections$23,452,926.17 
24.Reserve Account Draw Amount$0.00 
25.Available Funds$23,452,926.17 
Application of Available Funds
26.Servicing Fee0.15 %
a. Monthly Servicing Fee$309,651.97 
b. Amount Unpaid from Prior Months$0.00 
c. Amount Paid$309,651.97 
d. Shortfall Amount (a + b - c)$0.00 
27.Unreimbursed Servicer Advances$0.00 
28.Successor Servicer and Asset Representations Reviewer Unpaid Expenses and Indemnity Amounts
a. Successor Servicer Unpaid Transition Expenses and Indemnity Amounts (Capped at $175,000 annually)$0.00 
b. Successor Servicer Amount Paid$0.00 
c. Successor Servicer Shortfall Amount (a - b)$0.00 
d. Asset Representations Reviewer Fees, Expenses and Indemnity Amounts (Capped at $175,000 annually)$0.00 
e. Asset Representations Reviewer Amount Paid$0.00 
f. Asset Representations Reviewer Shortfall Amount (d - e)$0.00 
29.Class A Noteholder Interest Amounts
a. Class A-1 Monthly Interest$0.00 
b. Additional Note Interest related to Class A-1 Monthly Interest$0.00 
c. Interest Due on Additional Note Interest related to Class A-1 Monthly Interest$0.00 
d. Total Class A-1 Note Interest (sum a - c)$0.00 
e. Class A-2a Monthly Interest$0.00 
f. Additional Note Interest related to Class A-2a Monthly Interest$0.00 
g. Interest Due on Additional Note Interest related to Class A-2a Monthly Interest$0.00 
h. Total Class A-2a Note Interest (sum e - g)$0.00 
i. Class A-2b Monthly Interest$0.00 
j. Additional Note Interest related to Class A-2b Monthly Interest$0.00 
k. Interest Due on Additional Note Interest related to Class A-2b Monthly Interest$0.00 
l. Total Class A-2b Note Interest (sum i - k)$0.00 
m. Class A-3 Monthly Interest$690,475.05 
n. Additional Note Interest related to Class A-3 Monthly Interest$0.00 
o. Interest Due on Additional Note Interest related to Class A-3 Monthly Interest$0.00 
p. Total Class A-3 Note Interest (sum m - o)$690,475.05 
q. Class A-4 Monthly Interest$450,476.67 
r. Additional Note Interest related to Class A-4 Monthly Interest$0.00 
r. Additional Note Interest related to Class A-4 Monthly Interest$0.00 
t. Total Class A-4 Note Interest (sum q - s)$450,476.67 
30.Priority Principal Distributable Amount$0.00 
31.Class B Noteholder Interest Amount
a. Class B Monthly Interest$238,613.25 
b. Additional Note Interest related to Class B Monthly Interest$0.00 
c. Interest Due on Additional Note Interest related to Class B Monthly Interest$0.00 
d. Total Class B Note Interest (sum a - c)$238,613.25 
32.Secondary Principal Distributable Amount$0.00 
33.Class C Noteholder Interest Amount
a. Class C Monthly Interest$233,206.17 
b. Additional Note Interest related to Class C Monthly Interest$0.00 
c. Interest Due on Additional Note Interest related to Class C Monthly Interest$0.00 
d. Total Class C Note Interest (sum a - c)$233,206.17 
34.Tertiary Principal Distributable Amount$0.00 
35.Class D Noteholder Interest Amount
a. Class D Monthly Interest$217,544.67 
b. Additional Note Interest related to Class D Monthly Interest$0.00 
c. Interest Due on Additional Note Interest related to Class D Monthly Interest$0.00 
d. Total Class D Note Interest (sum a - c)$217,544.67 



36.Quaternary Principal Distributable Amount$1,576,965.29 
37.Required Payment Amount (Ln 26 + Ln 28 + (sum of Ln 29 through Ln 36))$3,716,933.07 
38.Reserve Account Deficiency$0.00 
39.Regular Principal Distributable Amount$18,987,348.77 
40.Remaining Unpaid Servicer Transition Expenses and Additional Servicing Fees, if any$0.00 
41.Remaining Unpaid Trustee and Asset Representations Reviewer Fees, Expenses and Indemnity Amounts, if any
a. Remaining Unpaid Trustee Fees, Expenses and Indemnity Amounts$0.00 
b. Remaining Unpaid Asset Representations Reviewer Fees, Expenses and Indemnity Amounts$0.00 
42.Remaining Unpaid Successor Servicer Indemnity Amounts, if any$0.00 
Collection Account Activity0.15 %
43.Deposits
a. Total Daily Deposits of Finance Charge Collections$3,487,618.09 
b. Total Daily Deposits of Principal Collections$19,903,551.81 
c. Withdrawal from Reserve Account$0.00 
d. Interest Income$61,756.27 
e. Total Deposits to Collection Account (sum a - d)$23,452,926.17 
44.Withdrawals
a. Servicing Fee and Unreimbursed Servicer Advances$309,651.97 
b. Successor Servicer Transition Expenses and Indemnity Amounts$0.00 
c. Deposit to Note Payment Account for Monthly Note Interest/Principal$22,394,629.87 
d. Deposit to Reserve Account$0.00 
e. Excess Collections (Deposit to Certificate Payment Account for payment to Certificateholder)$748,644.33 
f. Total Withdrawals from Collection Account (sum a - e)$23,452,926.17 
Note Payment Account Activity
45.Deposits
a. Class A-1 Interest Distribution$0.00 
b. Class A-2a Interest Distribution$0.00 
c. Class A-2b Interest Distribution$0.00 
d. Class A-3 Interest Distribution$690,475.05 
e. Class A-4 Interest Distribution$450,476.67 
f. Class B Interest Distribution$238,613.25 
g. Class C Interest Distribution$233,206.17 
h. Class D Interest Distribution$217,544.67 
i. Class A-1 Principal Distribution$0.00 
j. Class A-2a Principal Distribution$0.00 
k. Class A-2b Principal Distribution$0.00 
l. Class A-3 Principal Distribution$20,564,314.06 
m. Class A-4 Principal Distribution$0.00 
n. Class B Principal Distribution$0.00 
o. Class C Principal Distribution$0.00 
p. Class D Principal Distribution$0.00 
q. Total Deposits to Note Payment Account (sum a - p)$22,394,629.87 
46.Withdrawals
a. Class A-1 Distribution$0.00 
b. Class A-2a Distribution$0.00 
c. Class A-2b Distribution$0.00 
d. Class A-3 Distribution$21,254,789.11 
e. Class A-4 Distribution$450,476.67 
f. Class B Distribution$238,613.25 
g. Class C Distribution$233,206.17 
h. Class D Distribution$217,544.67 
i. Total Withdrawals from Note Payment Account (sum a - h)$22,394,629.87 



Certificate Payment Account Activity
47.Deposits to Certificate Payment Account from Excess Collections$748,644.33 
48.Withdrawals from Certificate Payment Account for Certificateholder Distribution$748,644.33 
Required Reserve Account Amount0.15 %
49.Required Reserve Account Amount (1.00% of Initial Pool Balance)$3,797,469.75 
Reserve Account Reconciliation
50.Beginning Balance (as of end of preceding Distribution Date)$3,797,469.75 
51.Investment Earnings$11,445.88 
52.Reserve Account Draw Amount$0.00 
53.Reserve Account Amount (Ln 50 + Ln 51 - Ln 52)$3,808,915.63 
54.Deposit from Available Funds (Ln 44d)$0.00 
55.If Reserve Account Balance exceeds Required Reserve Account Amount, payment to
a. the Note Payment Account for the payment of principal to the extent of any unfunded Regular Principal Distribution Amount; and$0.00 
b. any Successor Servicer for the payment of any unfunded Transition Costs and Additional Servicing Fee$0.00 
56.Payment to Depositor if Reserve Account Balance exceeds Required Reserve Account Amount and to the extent no unfunded amounts described in Ln 55 exist$11,445.88 
57.Ending Balance (Ln53 + Ln54 - Ln55 - Ln56)$3,797,469.75 
58.Reserve Account Deficiency (Ln50 - Ln57)$0.00 
Instructions to the Trustee
59.Amount to be deposited from the Reserve Account into the Collection Account$0.00 
60.Amount to be paid to Servicer from the Collection Account$309,651.97 
61.Amount to be deposited from the Collection Account into the Note Payment Account$22,394,629.87 
62.Amount to be deposited from the Collection Account into the Certificate Payment Account$748,644.33 
63.Amount to be deposited from the Collection Account into the Reserve Account$0.00 
64.Amount to be deposited from the Reserve Account, if Reserve Account Balance exceeds Required Reserve Account Amount, into
a. the Note Payment Account for any unfunded Regular Principal Distributable Amount$0.00 
b. the Depositor, if no unfunded Regular Principal distributable amount exists$11,445.88 
65.Amount to be paid to Class A-1 Noteholders from the Note Payment Account$0.00 
66.Amount to be paid to Class A-2a Noteholders from the Note Payment Account$0.00 
67.Amount to be paid to Class A-2b Noteholders from the Note Payment Account$0.00 
68.Amount to be paid to Class A-3 Noteholders from the Note Payment Account$21,254,789.11 
69.Amount to be paid to Class A-4 Noteholders from the Note Payment Account$450,476.67 
70.Amount to be paid to Class B Noteholders from the Note Payment Account$238,613.25 
71.Amount to be paid to Class C Noteholders from the Note Payment Account$233,206.17 
72.Amount to be paid to Class D Noteholders from the Note Payment Account$217,544.67 
73.Amount to be paid to Certificateholders from the Certificate Payment Account with respect to Excess Collections$748,644.33 



Delinquency Activity
Number of LoansPrincipal Balance
74.Delinquency Analysis
a. 31 to 60 days past due1,039$17,414,004.04 
b. 61 to 90 days past due605$10,812,431.57 
c. 91 to 120 days past due163$2,474,906.12 
d. 121 or more days past due1$2,837.68 
e. Total Past Due (sum a - d)1,808$30,704,179.41 
f. Delinquent Loans as a percentage of end of period Pool Balance (Ln 74e / Ln 5)8.7472 %
75.Has a Delinquency Trigger Event occurred?No
Loss Activity
Number of LoansPrincipal Balance
76.Defaulted Receivables (charge-offs)119$1,712,913.95 
77.Recoveries300$1,060,466.24 
78.Net Losses (Ln 76 - Ln 77)$652,447.71 
79.Ratio of Net Losses to Beginning of Period Pool Balance (Ln 78 / Ln 1)0.1756 %
Cumulative Loss Activity
Number of LoansPrincipal Balance
80.Defaulted Receivables (charge-offs)4,361$81,301,883.86 
81.Recoveries3,313$30,691,962.97 
82.Cumulative Net Losses (Ln 80 - Ln 81)$50,609,920.89 
83.Ratio of Cumulative Net Losses to Initial Pool Balance (Ln 82 / Ln 7)3.3318 %
84.Average Net Loss on Defaulted Receivables$11,605.12 
Other Servicing Information
85.Principal Balance of Receivables extended during the Collection Period$5,466,159.46 
86.Pool Balance on the close of the last day of the preceding Collection Period$371,582,358.88 
87.Ratio of extensions to pool balance (Ln 85 / Ln 86)1.47 %




IN WITNESS WHEREOF, the undersigned has duly executed this certificate on October 9, 2026
 
CARMAX BUSINESS SERVICES, LLC
As Servicer
By:/s/ Greg Dostich
Name:Greg Dostich
Title:Vice President and Treasurer