S&T Bancorp (STBA)

Employees’ Retirement Plan of S&T Bank

The Employees’ Retirement Plan of S&T Bank (the “Retirement Plan”) is a defined benefit pension plan that covers substantially all employees. The Retirement Plan provides benefits that are based on years of service and compensation. Benefits payable under the Retirement Plan at normal retirement, age 65, are determined under the following formula.

1.0% of Average Final Compensation up to Covered Compensation, times Benefit Service

Plus

1.5% of Average Final Compensation in excess of Covered Compensation, times Benefit Service

For purposes of determining the normal retirement benefit, the terms used above have the following meanings:

Participants’ benefits under the Retirement Plan are 100% vested after completion of five years. Participants who terminate employment prior to age 55 with a vested benefit are entitled to receive their full accrued benefit at normal retirement, age 65, or upon election, can receive actuarially reduced benefits as early as age 55. Participants who terminate employment after age 55 with at least 10 years of service are eligible to receive early retirement benefits under the Retirement Plan. Early retirement benefits are reduced 5/12 of 1% for each month by which the date benefit payments commence precedes age 62.

Accrued benefits under the Retirement Plan are payable in the form of a ten-year certain and life annuity that provides equal monthly payments for the participant’s life with a minimum of 120 monthly payments guaranteed. Married participants must receive their benefit in the form of a 50% joint and survivor annuity with 120 monthly payments guaranteed unless their spouse consents to a different form of a payment. A 50% joint and survivor annuity provides a reduced monthly payment for the participant’s life with 50% of the payment continuing for the spouse’s life following the participant’s death. Various optional annuity forms of payment are available under the Retirement Plan. All forms of payment are actuarially equivalent in value.

Employees’ Retirement Plan of S&T Bank

The Employees’ Retirement Plan of S&T Bank (“Plan”) is a defined benefit pension plan that covers substantially all employees. The Plan provides benefits that are based on years of service and compensation. Benefits payable under the Plan at normal retirement, age 65, are determined under the following formula.

1.0% of Average Final Compensation up to Covered Compensation, times Benefit Service

Plus

1.5% of Average Final Compensation in excess of Covered Compensation, times Benefit Service

For purposes of determining the normal retirement benefit, the terms used above have the following meanings:

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Participants’ benefits under the Plan are 100% vested after completion of five years. Participants who terminate employment prior to age 55 with a vested benefit are entitled to receive their full accrued benefit at normal retirement, age 65, or upon election, can receive actuarially reduced benefits as early as age 55. Participants who terminate employment after age 55 with at least 10 years of service are eligible to receive early retirement benefits under the Plan. Early retirement benefits are reduced 5/12 of 1% for each month by which the date benefit payments commence precedes age 62.

Accrued benefits under the Plan are payable in the form of a ten-year certain and life annuity that provides equal monthly payments for the participant’s life with a minimum of 120 monthly payments guaranteed. Married participants must receive their benefit in the form of a 50% joint and survivor annuity with 120 monthly payments guaranteed unless their spouse consents to a different form of a payment. A 50% joint and survivor annuity provides a reduced monthly payment for the participant’s life with 50% of the payment continuing for the spouse’s life following the participant’s death. Various optional annuity forms of payment are available under the Plan. All forms of payment are actuarially equivalent in value.