Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Current assets
Cash and cash equivalents	$ 5,620	$ 5,598
Accounts receivable, net of allowance for credit losses of $251 and $226	5,012	4,874
Equipment installment plan receivables, net of allowance for credit losses and unamortized discount of $723 and $733	4,530	4,997
Inventory	3,085	2,405
Prepaid expenses	909	1,215
Other current assets	2,686	5,372
Total current assets	21,842	24,461
Property and equipment, net	36,035	38,333
Operating lease right-of-use assets	24,208	25,692
Financing lease right-of-use assets	2,987	2,760
Goodwill	13,665	13,678
Spectrum licenses	99,980	98,032
Other intangible assets, net	3,066	3,843
Equipment installment plan receivables due after one year, net of allowance for credit losses and unamortized discount of $199 and $213	2,457	2,683
Other assets	8,864	9,755
Total assets	213,104	219,237
Current liabilities
Accounts payable and accrued liabilities	8,624	10,280
Short-term debt	6,343	5,135
Deferred revenue	1,407	1,533
Short-term operating lease liabilities	3,644	3,814
Short-term financing lease liabilities	1,158	1,163
Other current liabilities	2,815	2,575
Total current liabilities	23,991	24,500
Tower obligations	3,419	3,532
Deferred tax liabilities	21,715	19,583
Operating lease liabilities	25,017	26,371
Financing lease liabilities	1,136	1,107
Other long-term liabilities	4,196	3,794
Total long-term liabilities	132,806	135,534
Commitments and contingencies (Note 14)
Stockholders' equity
Common stock, par value $0.00001 per share, 2,000,000,000 shares authorized; 1,280,056,882 and 1,275,774,235 shares issued, 1,062,845,266 and 1,106,930,661 shares outstanding	0	0
Additional paid-in capital	70,089	69,460
Treasury stock, at cost, 217,211,616 and 168,843,574 shares	(40,102)	(30,545)
Accumulated other comprehensive loss	(595)	(848)
Retained earnings	26,915	21,136
Total stockholders' equity	56,307	59,203
Total liabilities and stockholders' equity	213,104	219,237
Nonrelated Party
Current liabilities
Long-term debt	77,323	79,649
Related Party
Current liabilities
Long-term debt	$ 0	$ 1,498

Sale Leaseback Transaction, Tower Obligation

No definition available.

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Namespace Prefix:	tmus_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.