FFIN · First Financial Bankshares Inc

The reporting person executed a trade order through a broker-dealer which resulted in multiple same day, same way open market purchases, with prices ranging from $34.65 to $34.67 per share, inclusive. The reporting person has reported these purchases on an aggregate basis using the weighted average price for the transactions. The reporting person undertakes to provide to the Company, any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price.

In connection with the vesting on August 16, 2026, of 1,354 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,354 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,354 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,354 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 1,354 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,354 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,354 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,354 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 1,354 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,354 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,354 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,354 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

The reporting person elected, in accordance with the Registrant's 2021 Omnibus Stock and Incentive Plan, to exercise his right to have the Registrant withhold 120 shares of the Registrant's common stock to pay income taxes related to vesting of previously granted restricted stock units.

In connection with the vesting on August 16, 2026, of 1,354 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,354 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,354 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,354 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 639 restricted stock units previously granted to the reporting person, the reporting person's receipt of 639 shares of common stock was deferred resulting in the reporting person's receipt instead of 639 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 639 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 714 restricted stock units previously granted to the reporting person, the reporting person's receipt of 714 shares of common stock was deferred resulting in the reporting person's receipt instead of 714 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 714 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 526 restricted stock units previously granted to the reporting person, the reporting person's receipt of 526 shares of common stock was deferred resulting in the reporting person's receipt instead of 526 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 526 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 564 restricted stock units previously granted to the reporting person, the reporting person's receipt of 564 shares of common stock was deferred resulting in the reporting person's receipt instead of 564 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 564 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 639 restricted stock units previously granted to the reporting person, the reporting person's receipt of 639 shares of common stock was deferred resulting in the reporting person's receipt instead of 639 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 639 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 526 restricted stock units previously granted to the reporting person, the reporting person's receipt of 526 shares of common stock was deferred resulting in the reporting person's receipt instead of 526 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 526 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 714 restricted stock units previously granted to the reporting person, the reporting person's receipt of 714 shares of common stock was deferred resulting in the reporting person's receipt instead of 714 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 714 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 16, 2026, of 564 restricted stock units previously granted to the reporting person, the reporting person's receipt of 564 shares of common stock was deferred resulting in the reporting person's receipt instead of 564 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 564 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 14, 2026, of 2,375 restricted stock units previously granted to the reporting person, the reporting person's receipt of 2,375 shares of common stock was deferred resulting in the reporting person's receipt instead of 2,375 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 2,375 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 14, 2026, of 1,825 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,825 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,825 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,825 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

The options vest 33.33% after one year from the grant date, 66.66% after the second year, and 100% after the third year.

In connection with the vesting on August 14, 2026, of 880 restricted stock units previously granted to the reporting person, the reporting person's receipt of 880 shares of common stock was deferred resulting in the reporting person's receipt instead of 880 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 880 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 14, 2026, of 880 restricted stock units previously granted to the reporting person, the reporting person's receipt of 880 shares of common stock was deferred resulting in the reporting person's receipt instead of 880 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 880 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

Reflects grant of restricted stock units (RSUs) which vest in three approximately equal installments on each of the three anniversaries of the grant date.

In connection with the vesting on August 14, 2026, of 2,375 restricted stock units previously granted to the reporting person, the reporting person's receipt of 2,375 shares of common stock was deferred resulting in the reporting person's receipt instead of 2,375 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 2,375 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 14, 2026, of 2,337 restricted stock units previously granted to the reporting person, the reporting person's receipt of 2,337 shares of common stock was deferred resulting in the reporting person's receipt instead of 2,337 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 2,337 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 14, 2026, of 452 restricted stock units previously granted to the reporting person, the reporting person's receipt of 452 shares of common stock was deferred resulting in the reporting person's receipt instead of 452 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 452 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

Reflects grant of restricted stock units (RSUs) which vest in three approximately equal installments on each of the three anniversaries of the grant date.

In connection with the vesting on August 14, 2026, of 1,100 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,100 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,100 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,100 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

The options vest 33.33% after one year from the grant date, 66.66% after the second year, and 100% after the third year.

Reflects grant of restricted stock units (RSUs) which vest in three approximately equal installments on each of the three anniversaries of the grant date.

Represents shares held by several trusts of which Mr. Dueser is trustee, settlor and beneficiary.

In connection with the vesting on August 14, 2026, of 1,519 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,519 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,519 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,519 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

Reflects grant of restricted stock units (RSUs) which vest in three approximately equal installments on each of the three anniversaries of the grant date.

In connection with the vesting on August 14, 2026, of 1,100 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,100 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,100 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,100 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

In connection with the vesting on August 14, 2026, of 1,519 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,519 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,519 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,519 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

The options vest 33.33% after one year from the grant date, 66.66% after the second year, and 100% after the third year.

In connection with the vesting on August 14, 2026, of 8,875 restricted stock units previously granted to the reporting person, the reporting person's receipt of 8,875 shares of common stock was deferred resulting in the reporting person's receipt instead of 8,875 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 8,875 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

Represents shares held by several trusts of which Mr. Dueser is trustee, settlor and beneficiary.

The options vest 33.33% after one year from the grant date, 66.66% after the second year, and 100% after the third year.

Reflects grant of restricted stock units (RSUs) which vest in three approximately equal installments on each of the three anniversaries of the grant date.

Reflects grant of restricted stock units (RSUs) which vest in three approximately equal installments on each of the three anniversaries of the grant date.

The options vest 33.33% after one year from the grant date, 66.66% after the second year, and 100% after the third year.

The reporting person elected, in accordance with the Registrant's 2021 Omnibus Stock and Incentive Plan, to exercise his right to have the Registrant withhold 94 shares of the Registrant's common stock to pay income taxes related to vesting of previously granted restricted stock units.

In connection with the vesting on August 14, 2026, of 1,825 restricted stock units previously granted to the reporting person, the reporting person's receipt of 1,825 shares of common stock was deferred resulting in the reporting person's receipt instead of 1,825 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 1,825 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

Reflects grant of restricted stock units (RSUs) which vest in three approximately equal installments on each of the three anniversaries of the grant date.

The options vest 33.33% after one year from the grant date, 66.66% after the second year, and 100% after the third year.

The reporting person elected, in accordance with the Registrant's 2021 Omnibus Stock and Incentive Plan, to exercise his right to have the Registrant withhold 111 shares of the Registrant's common stock to pay income taxes related to vesting of previously granted restricted stock units.

In connection with the vesting on August 14, 2026, of 8,875 restricted stock units previously granted to the reporting person, the reporting person's receipt of 8,875 shares of common stock was deferred resulting in the reporting person's receipt instead of 8,875 shares of deferred stock units into the First Financial Bankshares, Inc. Supplemental Executive Retirement Plan, as amended and restated effected July 26, 2022 (the "SERP"). The reporting person is therefore reporting the disposition of 8,875 restricted stock units in exchange for an equal number of deferred stock units under the SERP, which are payable upon the reporting person's termination.

The reporting person elected, in accordance with the Registrant's 2021 Omnibus Stock and Incentive Plan, to exercise his right to have the Registrant withhold 266 shares of the Registrant's common stock to pay income taxes related to vesting of previously granted restricted stock units.