CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Operating Activities
Net income	$ 7,456	$ 4,559
Adjustments to reconcile net income to net cash provided by operating activities:
Client incentives	3,989	3,219
Share-based compensation (Note 9)	242	183
Depreciation and amortization of property, equipment, technology and intangible assets	450	409
Deferred income taxes	(1,133)	1,715
Right to recover for covered losses recorded in equity (Note 2)	(9)	(165)
Charitable contribution of Visa Inc. shares (Note 10)	0	192
Other	(44)	30
Change in operating assets and liabilities:
Settlement receivable	(239)	42
Accounts receivable	(82)	(34)
Client incentives	(3,483)	(3,376)
Other assets	(143)	(192)
Accounts payable	(18)	(71)
Settlement payable	379	(19)
Accrued and other liabilities	1,408	(65)
Accrued litigation (Note 11)	446	14
Net cash provided by operating activities	9,219	6,441
Investing Activities
Purchases of property, equipment, technology and intangible assets	(523)	(512)
Proceeds from sales of property, equipment and technology	14	0
Investment securities, available-for-sale:
Purchases	(3,354)	(1,877)
Proceeds from maturities and sales	2,789	4,296
Acquisition of business, net of cash received	(196)	(302)
Purchases of / contributions to other investments	(35)	(18)
Net cash (used in) provided by investing activities	(1,305)	1,587
Financing Activities
Repurchase of class A common stock (Note 7)	(5,604)	(5,170)
Repayments of long-term debt (Note 4)	(1,750)	0
Dividends paid (Note 7)	(1,435)	(1,189)
Deposits into litigation escrow account- U.S. Retrospective Responsibility Plan	(600)	0
Payments from litigation escrow account—U.S. retrospective responsibility plan (Note 2 and Note 11)	150	0
Cash proceeds from issuance of common stock under employee equity plans	135	128
Restricted stock and performance-based shares settled in cash for taxes	(90)	(73)
Net cash used in financing activities	(9,194)	(6,304)
Effect of exchange rate changes on cash and cash equivalents	(89)	94
(Decrease) increase in cash and cash equivalents	(1,369)	1,818
Cash and cash equivalents at beginning of period	9,874	5,619
Cash and cash equivalents at end of period	8,505	7,437
Supplemental Disclosure
Income taxes paid, net of refunds	1,649	2,239
Interest payments on debt (Note 4)	510	489
Accruals related to purchases of property, equipment, technology and intangible assets	$ 35	$ 35