TMUS · T-Mobile US, Inc.

The transactions reported on this Form 4 were effected pursuant to a 10b5-1 trading plan adopted on November 29, 2023.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $165.905 to $166.19 per share. The holder undertakes to provide to the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

The transactions reported on this Form 4 were effected pursuant to a 10b5-1 trading plan adopted on November 29, 2023.

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $164.91 to $165.90 per share. The holder undertakes to provide to the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Represents restricted stock units granted under the Issuer's 2023 Incentive Award Plan; such units vest in full on June 16, 2027 (the one-year anniversary of the grant), subject to the terms of the Issuer's Director Compensation Program.

Represents restricted stock units granted under the Issuer's 2023 Incentive Award Plan; such units vest in full on June 16, 2027 (the one-year anniversary of the grant), subject to the terms of the Issuer's Director Compensation Program.

Represents restricted stock units granted under the Issuer's 2023 Incentive Award Plan; such units vest in full on June 16, 2027 (the one-year anniversary of the grant), subject to the terms of the Issuer's Director Compensation Program.

Represents restricted stock units granted under the Issuer's 2023 Incentive Award Plan; such units vest in full on June 16, 2027 (the one-year anniversary of the grant), subject to the terms of the Issuer's Director Compensation Program.

Represents restricted stock units granted under the Issuer's 2023 Incentive Award Plan; such units vest in full on June 16, 2027 (the one-year anniversary of the grant).

Represents restricted stock units granted under the Issuer's 2023 Incentive Award Plan; such units vest in full on June 16, 2027 (the one-year anniversary of the grant), subject to the terms of the Issuer's Director Compensation Program.

Represents restricted stock units granted under the Issuer's 2023 Incentive Award Plan; such units vest in full on June 16, 2027 (the one-year anniversary of the grant), subject to the terms of the Issuer's Director Compensation Program.

Represents dividends accrued on vested restricted stock units.

Includes acquisition of shares of common stock under the issuer's Amended and Restated 2014 Employee Stock Purchase Plan.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 19, 2026.

Includes acquisition of shares of common stock under the issuer's Amended and Restated 2014 Employee Stock Purchase Plan.

The price reported in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $195.74 to $196.115. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth on this footnote.

The price reported in Column 4 is a weighted average purchase price. These shares were bought in multiple transactions at prices ranging from $196.12 to $196.18. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares bought at each separate price within the range set forth on this footnote.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Includes acquisition of shares of common stock under the issuer's Amended and Restated 2014 Employee Stock Purchase Plan.

Represents dividends accrued on vested restricted stock units.

Mr. Datar is a co-manager of Datar Investment LLC, Safari LLC, and Legacycap LLC and has shared voting and investment power over the securities held by these entities.

The price reported in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $221.00 to $221.25. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth on this footnote.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

The price reported in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $220.83 to $222.95. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth on this footnote.

The price reported in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $222.37 to $222.40. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth on this footnote.

The price reported in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $220.00 to $220.56. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth on this footnote.

The price reported in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $214.23 to $215.34. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth on this footnote.

This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 24, 2025.

The price reported in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $214.68 to $215.13. The reporting person undertakes to provide the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth on this footnote.

This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 24, 2025.

Represents shares withheld for payment of taxes on vesting of performance-based restricted stock units; not an open market transaction.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-third of the units vest on each of February 15, 2027, February 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Represents performance-based restricted stock units earned under the issuer's 2015 Sprint Omnibus Incentive Plan, that vested on February 15, 2026 based on the Company's relative total shareholder return during the three-year period ending February 15, 2026.

Represents performance-based restricted stock units earned under the issuer's 2013 Omnibus Incentive Plan that vested on February 15, 2026 based on the Company's relative total shareholder return during the three-year period ending February 15, 2026.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-third of the units vest on each of February 15, 2027, February 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.

Represents performance-based restricted stock units earned under the issuer's 2013 Omnibus Incentive Plan that vested on February 15, 2026 based on the Company's relative total shareholder return during the three-year period ending February 15, 2026.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-third of the units vest on each of February 15, 2027, February 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-third of the units vest on each of February 15, 2027, February 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-third of the units vest on each of February 15, 2027, February 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.

Represents shares withheld for payment of taxes on vesting of performance-based restricted stock units; not an open market transaction.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-third of the units vest on each of February 15, 2027, February 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-sixth of the units vest on each of August 15, 2026, February 15, 2027, August 15, 2027, February 15, 2028, August 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-third of the units vest on each of February 15, 2027, February 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.

Represents shares withheld for payment of taxes on vesting of performance-based restricted stock units; not an open market transaction.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Represents shares withheld for payment of taxes on vesting of restricted stock units; not an open market transaction.

Represents shares withheld for payment of taxes on vesting of performance-based restricted stock units; not an open market transaction.

Represents restricted stock units granted under the issuer's 2023 Incentive Award Plan, (the "Plan"); one-third of the units vest on each of February 15, 2027, February 15, 2028 and February 15, 2029, subject to the terms of the Plan and related award agreement.