CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities
Net income	$ 9,553	$ 8,436
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Client incentives	6,605	5,691
Share-based compensation	451	400
Depreciation and amortization	496	461
Deferred income taxes	(68)	(154)
VE territory covered losses incurred	(60)	(15)
(Gains) losses on equity investments, net	26	196
Other	58	(22)
Change in operating assets and liabilities:
Settlement receivable	(1,335)	147
Accounts receivable	34	(67)
Client incentives	(7,088)	(5,521)
Other assets	(258)	(77)
Accounts payable	(25)	(48)
Settlement payable	1,143	(493)
Accrued and other liabilities	(1,479)	(1,047)
Accrued litigation	99	144
Net cash provided by (used in) operating activities	8,152	8,031
Investing Activities
Purchases of property, equipment and technology	(548)	(459)
Investment securities:
Purchases	(3,686)	(2,487)
Proceeds from maturities and sales	2,145	1,760
Acquisitions, net of cash and restricted cash acquired	(915)	0
Purchases of other investments	(14)	(70)
Settlement of derivative instruments	0	402
Other investing activities	(47)	19
Net cash provided by (used in) investing activities	(3,065)	(835)
Financing Activities
Repurchase of class A common stock	(6,338)	(5,309)
Repayments of debt	0	(2,250)
Dividends paid	(2,120)	(1,886)
Cash proceeds from issuance of class A common stock under equity plans	183	118
Restricted stock and performance-based shares settled in cash for taxes	(181)	(118)
Other financing activities	203	172
Net cash provided by (used in) financing activities	(8,253)	(9,273)
Effect of exchange rate changes on cash, cash equivalents, restricted cash and restricted cash equivalents	124	828
Increase (decrease) in cash, cash equivalents, restricted cash and restricted cash equivalents	(3,042)	(1,249)
Cash, cash equivalents, restricted cash and restricted cash equivalents at beginning of period	21,990	20,377
Cash, cash equivalents, restricted cash and restricted cash equivalents at end of period	18,948	19,128
Supplemental Disclosure
Cash paid for income taxes, net	3,658	2,635
Interest payments on debt	261	293
Accruals related to purchases of property, equipment and technology	$ 99	$ 148