Exhibit 99.1

MONTHLY SERVICER'S CERTIFICATE

CARMAX BUSINESS SERVICES, LLC

CARMAX AUTO OWNER TRUST

SERIES 2020-1

Collection Period

09/01/23-09/30/23

Determination Date

10/9/2023

Distribution Date

10/16/2023

Additional information, including defined terms, can be found in the prospectus on the SEC's EDGAR system (http://www.sec.gov) under File No. 333-228375-05.


Pool Balance
1.	Pool Balance on the close of the last day of the preceding Collection Period			$	223,921,867.69
2.	Collections allocable to Principal			$	13,920,327.63
3.	Purchase Amount allocable to Principal			$	0.00
4.	Defaulted Receivables			$	266,879.51
5.	Pool Balance on the close of the last day of the related Collection Period			$	209,734,660.55
	(Ln1 - Ln2 - Ln3 - Ln4)
6.	Total number of Receivables outstanding on the close of the last day of the related Collection Period			31,394
7.	Initial Pool Balance			$	1,553,875,032.29
		Beginning of Period		End of Period
8.	Note Balances
	a. Class A-1 Note Balance	$	0.00	$	0.00
	b. Class A-2 Note Balance	$	0.00	$	0.00
	c. Class A-3 Note Balance	$	6,147,180.11	$	0.00
	d. Class A-4 Note Balance	$	115,200,000.00	$	107,159,972.97
	e. Class B Note Balance	$	37,290,000.00	$	37,290,000.00
	f. Class C Note Balance	$	35,000,000.00	$	35,000,000.00
	g. Class D Note Balance	$	26,400,000.00	$	26,400,000.00
	h. Note Balance (sum a - g)	$	220,037,180.11	$	205,849,972.97
9.	Pool Factors
	a. Class A-1 Note Pool Factor	0.0000000		0.0000000
	b. Class A-2 Note Pool Factor	0.0000000		0.0000000
	c. Class A-3 Note Pool Factor	0.0125376		0.0000000
	d. Class A-4 Note Pool Factor	1.0000000		0.9302081
	e. Class B Note Pool Factor	1.0000000		1.0000000
	f. Class C Note Pool Factor	1.0000000		1.0000000
	g. Class D Note Pool Factor	1.0000000		1.0000000
	h. Note Pool Factor	0.1419604		0.1328073
10.	Overcollateralization Target Amount			$	3,884,687.58
11.	Current overcollateralization amount (Pool Balance - Note Balance)			$	3,884,687.58
12.	Weighted Average Coupon			8.60		%
13.	Weighted Average Original Term	months		68.15
14.	Weighted Average Remaining Term	months		21.36
Collections
15.	Finance Charges:
	a. Collections allocable to Finance Charge			$	1,628,779.11
	b. Liquidation Proceeds allocable to Finance Charge			$	1,851.54
	c. Purchase Amount allocable to Finance Charge			$	0.00
	d. Available Finance Charge Collections (sum a - c)			$	1,630,630.65
16.	Principal:
	a. Collections allocable to Principal			$	13,920,327.63
	b. Liquidation Proceeds allocable to Principal			$	193,077.81
	c. Purchase Amount allocable to Principal			$	0.00
	d. Available Principal Collections (sum a - c)			$	14,113,405.44


17.	Total Finance Charge and Principal Collections (15d + 16d)	$	15,744,036.09
18.	Interest Income from Collection Account	$	60,409.97
19.	Simple Interest Advances	$	0.00
20.	Available Collections (Ln17 + 18 + 19)	$	15,804,446.06
Available Funds
21.	Available Collections	$	15,804,446.06
22.	Reserve Account Draw Amount	$	0.00
23.	Available Funds	$	15,804,446.06
Application of Available Funds
24.	Servicing Fee	0.15		%
	a. Monthly Servicing Fee	$	186,601.56
	b. Amount Unpaid from Prior Months	$	0.00
	c. Amount Paid	$	186,601.56
	d. Shortfall Amount (a + b - c)	$	0.00
25.	Unreimbursed Servicer Advances	$	0.00
26.	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
27.	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-2 Monthly Interest	$	0.00
	f. Additional Note Interest related to Class A-2 Monthly Interest	$	0.00
	g. Interest Due on Additional Note Interest related to Class A-2 Monthly Interest	$	0.00
	h. Total Class A-2 Note Interest (sum e - g)	$	0.00
	i. Class A-3 Monthly Interest	$	9,681.81
	j. Additional Note Interest related to Class A-3 Monthly Interest	$	0.00
	k. Interest Due on Additional Note Interest related to Class A-3 Monthly Interest	$	0.00
	l. Total Class A-3 Note Interest (sum i - k)	$	9,681.81
	m. Class A-4 Monthly Interest	$	194,880.00
	n. Additional Note Interest related to Class A-4 Monthly Interest	$	0.00
	o. Interest Due on Additional Note Interest related to Class A-4 Monthly Interest	$	0.00
	p. Total Class A-4 Note Interest (sum m - o)	$	194,880.00
28.	Priority Principal Distributable Amount	$	0.00
29.	Class B Noteholder Interest Amount
	a. Class B Monthly Interest	$	68,675.75
	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)	$	68,675.75
30.	Secondary Principal Distributable Amount	$	0.00
31.	Class C Noteholder Interest Amount
	a. Class C Monthly Interest	$	68,250.00
	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)	$	68,250.00
32.	Tertiary Principal Distributable Amount	$	0.00

33.

Class D Noteholder Interest Amount


	a. Class D Monthly Interest	$	58,080.00
	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)	$	58,080.00
34.	Quaternary Principal Distributable Amount	$	10,302,519.56
35.	Required Payment Amount (Ln 24 + Ln 26 + (sum of Ln 27 through Ln 34))	$	10,888,688.68
36.	Reserve Account Deficiency	$	0.00
37.	Regular Principal Distributable Amount	$	3,884,687.58
38.	Remaining Unpaid Servicer Transition Expenses and Additional Servicing Fees, if any	$	0.00
39.	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
40.	Remaining Unpaid Successor Servicer Indemnity Amounts, if any	$	0.00
Collection Account Activity		0.15		%
41.	Deposits
	a. Total Daily Deposits of Finance Charge Collections	$	1,630,630.65
	b. Total Daily Deposits of Principal Collections	$	14,113,405.44
	c. Withdrawal from Reserve Account	$	0.00
	d. Interest Income	$	60,409.97
	e. Total Deposits to Collection Account (sum a - d)	$	15,804,446.06
42.	Withdrawals
	a. Servicing Fee and Unreimbursed Servicer Advances	$	186,601.56
	b. Successor Servicer Transition Expenses and Indemnity Amounts	$	0.00
	c. Deposit to Note Payment Account for Monthly Note Interest/Principal	$	14,586,774.70
	d. Deposit to Reserve Account	$	0.00
	e. Excess Collections (Deposit to Certificate Payment Account for payment to Certificateholder)	$	1,031,069.80
	f. Total Withdrawals from Collection Account (sum a - e)	$	15,804,446.06
Note Payment Account Activity
43.	Deposits
	a. Class A-1 Interest Distribution	$	0.00
	b. Class A-2 Interest Distribution	$	0.00
	c. Class A-3 Interest Distribution	$	9,681.81
	d. Class A-4 Interest Distribution	$	194,880.00
	e. Class B Interest Distribution	$	68,675.75
	f. Class C Interest Distribution	$	68,250.00
	g. Class D Interest Distribution	$	58,080.00
	h. Class A-1 Principal Distribution	$	0.00
	i. Class A-2 Principal Distribution	$	0.00
	j. Class A-3 Principal Distribution	$	6,147,180.11
	k. Class A-4 Principal Distribution	$	8,040,027.03
	l. Class B Principal Distribution	$	0.00
	m. Class C Principal Distribution	$	0.00
	n. Class D Principal Distribution	$	0.00
	o. Total Deposits to Note Payment Account (sum a - n)	$	14,586,774.70
44.	Withdrawals
	a. Class A-1 Distribution	$	0.00
	b. Class A-2 Distribution	$	0.00
	c. Class A-3 Distribution	$	6,156,861.92
	d. Class A-4 Distribution	$	8,234,907.03
	e. Class B Distribution	$	68,675.75


f. Class C Distribution	$	68,250.00
g. Class D Distribution	$	58,080.00
h. Total Withdrawals from Note Payment Account (sum a - g)	$	14,586,774.70


Certificate Payment Account Activity
45.	Deposits to Certificate Payment Account from Excess Collections	$	1,031,069.80
46.	Withdrawals from Certificate Payment Account for Certificateholder Distribution	$	1,031,069.80
Required Reserve Account Amount		0.15		%
47.	Required Reserve Account Amount (0.25% of Initial Pool Balance)	$	3,884,687.58
Reserve Account Reconciliation
48.	Beginning Balance (as of end of preceding Distribution Date)	$	3,884,687.58
49.	Investment Earnings	$	16,563.06
50.	Reserve Account Draw Amount	$	0.00
51.	Reserve Account Amount (Ln 48 + Ln 49 - Ln 50)	$	3,901,250.64
52.	Deposit from Available Funds (Ln 42d)	$	0.00
53.	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
54.	Payment to Depositor if Reserve Account Balance exceeds Required Reserve Account Amount and to the extent no unfunded amounts described in Ln 53 exist	$	16,563.06
55.	Ending Balance (Ln51 + Ln52 - Ln53 - Ln54)	$	3,884,687.58
56.	Reserve Account Deficiency (Ln48 - Ln55)	$	0.00
Instructions to the Trustee
57.	Amount to be deposited from the Reserve Account into the Collection Account	$	0.00
58.	Amount to be paid to Servicer from the Collection Account	$	186,601.56
59.	Amount to be deposited from the Collection Account into the Note Payment Account	$	14,586,774.70
60.	Amount to be deposited from the Collection Account into the Certificate Payment Account	$	1,031,069.80
61.	Amount to be deposited from the Collection Account into the Reserve Account	$	0.00
62.	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	$	16,563.06
63.	Amount to be paid to Class A-1 Noteholders from the Note Payment Account	$	0.00
64.	Amount to be paid to Class A-2 Noteholders from the Note Payment Account	$	0.00
65.	Amount to be paid to Class A-3 Noteholders from the Note Payment Account	$	6,156,861.92
66.	Amount to be paid to Class A-4 Noteholders from the Note Payment Account	$	8,234,907.03
67.	Amount to be paid to Class B Noteholders from the Note Payment Account	$	68,675.75
68.	Amount to be paid to Class C Noteholders from the Note Payment Account	$	68,250.00
69.	Amount to be paid to Class D Noteholders from the Note Payment Account	$	58,080.00
70.	Amount to be paid to Certificateholders from the Certificate Payment Account with respect to Excess Collections	$	1,031,069.80


Delinquency Activity
		Number of Loans	Principal Balance
71.	Delinquency Analysis
	a. 31 to 60 days past due	728	$	7,414,458.37
	b. 61 to 90 days past due	377	$	3,975,572.54
	c. 91 to 120 days past due	97	$	1,003,736.92
	d. 121 or more days past due	0	$	0.00
	e. Total Past Due (sum a - d)	1,202	$	12,393,767.83
	f. Delinquent Loans as a percentage of end of period Pool Balance (Ln 71e / Ln 5)		5.9093		%

72.	Has a Delinquency Trigger Event occurred?		No

Loss Activity
		Number of Loans	Principal Balance

73.	Defaulted Receivables (charge-offs)	39	$	266,879.51
74.	Recoveries	128	$	194,929.35
75.	Net Losses (Ln 73 - Ln 74)		$	71,950.16
76.	Ratio of Net Losses to Beginning of Period Pool Balance (Ln 75 / Ln 1)		0.0321		%

Cumulative Loss Activity
		Number of Loans	Principal Balance

77.	Defaulted Receivables (charge-offs)	2,721	$	37,751,710.23
78.	Recoveries	2,224	$	19,651,528.11
79.	Cumulative Net Losses (Ln 77 - Ln 78)		$	18,100,182.12
80.	Ratio of Cumulative Net Losses to Initial Pool Balance (Ln 79 / Ln 7)		1.1648		%
81.	Average Net Loss on Defaulted Receivables		$	6,652.03

Other Servicing Information

82.	Principal Balance of Receivables extended during the Collection Period		$	2,367,533.82
83.	Pool Balance on the close of the last day of the preceding Collection Period		$	223,921,867.69
84.	Ratio of extensions to pool balance (Ln 82 / Ln 83)		1.06		%

IN WITNESS WHEREOF, the undersigned has duly executed this certificate on October 9, 2023.


CARMAX BUSINESS SERVICES, LLC

As Servicer

By:			/s/ Andrew J. McMonigle

Name:			Andrew J. McMonigle

Title:			Vice President and Treasurer

CarMax Auto Owner Trust 2020-1 10-D