144 0000946770 XXXXXXXX LIVE 0001283699 T-Mobile US, Inc. 001-33409 12920 SE 38TH STREET BELLEVUE WA 98006 800-318-9270 Deutsche Telekom AG 10% Stockholder Common Stock Santander US Capital Markets LLC

437 Madison Avenue New York NY 10022

5000000 1201900000 1125419038 09/11/2025 NASDAQ Common Stock 05/31/2001 Merger or Acquisition Issuer N 5000000 05/31/2001 Not Applicable N 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/12/2025 69840 15975879.05 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/13/2025 69840 15920349.26 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/16/2025 69840 16074507.1 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/17/2025 69840 15466556.88 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/18/2025 69840 15481432.8 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/20/2025 69840 15490428.19 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/23/2025 69840 15755910.98 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/24/2025 69840 16018656.05 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/25/2025 69840 16102093.9 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/26/2025 69840 16106018.9 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/27/2025 69840 16402936.68 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 06/30/2025 69840 16594437.96 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/01/2025 69840 16866122.54 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/02/2025 69840 16614426.17 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/03/2025 69840 16734460.18 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/07/2025 69840 16627458.31 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/08/2025 69840 16449233.62 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/09/2025 69840 16222065.05 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/10/2025 69840 15961024.08 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/11/2025 69840 15892273.58 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/14/2025 69840 15947384.33 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/15/2025 69840 15794371.87 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/16/2025 69840 15943263.77 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/17/2025 69840 15877125.29 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/18/2025 69840 15862912.85 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/21/2025 69840 16243338.31 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/22/2025 69840 16316726.18 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/23/2025 69840 16246928.09 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/24/2025 69840 17344072.58 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/25/2025 69840 17109249.55 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/28/2025 69840 16664466.53 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/29/2025 69840 16711063.78 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/30/2025 69840 16837355.45 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 07/31/2025 69840 16739781.98 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/01/2025 69840 16613734.75 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/04/2025 69840 16708605.41 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/05/2025 69840 16695056.45 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/06/2025 69840 16741220.69 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastri P7 6221

Common Stock 08/07/2025 69840 16847845.42 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/08/2025 69840 17124341.98 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/11/2025 69840 17287781.54 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/12/2025 69840 17534344.68 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/13/2025 69840 17566128.86 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/14/2025 69840 17520676.99 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/15/2025 69840 17756072.71 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/18/2025 69840 17841445.13 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/19/2025 69840 17965096.85 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/20/2025 69840 18149404.61 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/21/2025 69840 18027177.62 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/22/2025 69840 17794638.36 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/25/2025 69840 17552000.23 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/26/2025 69840 17507239.78 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/27/2025 69840 17554018.61 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/28/2025 69840 17496631.08 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 08/29/2025 69840 17545798.44 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 09/02/2025 69840 17909902.3 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 09/03/2025 69840 17634362.54 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 09/04/2025 69840 17665050.24 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 09/05/2025 69840 17674499.59 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 09/08/2025 69840 17003860.99 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 09/09/2025 69840 16932505.46 10b5-1 Sales for Deutsche Telekom Holding B.V.

Stationsplein 8K BT Maastricht P7 6221

Common Stock 09/10/2025 69840 16767250.06 Deutsche Telekom Holding B.V. ("DT Holding"), an indirect wholly-owned subsidiary of Deutsche Telekom AG, holds the shares to be sold. On June 12, 2025, DT Holding entered into a Rule 10b5-1 trading plan with Santander US Capital Markets LLC (the "Santander Plan"), which contemplates sales of up to 5,000,000 shares of Common Stock. Aggregate Market Value of shares is calculated based on a closing share price of $240.38 on September 10, 2025. Any sales by the reporting person will occur under the terms of the Santander Plan, which contemplates sales of the Common Stock from September 11, 2025, through December 30, 2025, under the parameters set forth in such trading plan. 09/10/2025 06/12/2025 /s/ Christoph Appel, Attorney-in-fact