(a) General rule. An hour of service which must, as a minimum, be counted for the purposes of determining a year of service, a year of participation for benefit accrual, a break in service and employment commencement date (or reemployment commencement date) under sections 202, 203 and 204 of the Act and sections 410 and 411 of the Code, is an hour of service as defined in paragraphs (a)(1), (2) and (3) of this section. The employer may round up hours at the end of a computation period or more frequently.

1. (1) An hour of service is each hour for which an employee is paid, or entitled to payment, for the performance of duties for the employer during the applicable computation period.

2. (2) An hour of service is each hour for which an employee is paid, or entitled to payment, by the employer on account of a period of time during which no duties are performed (irrespective of whether the employment relationship has terminated) due to vacation, holiday, illness, incapacity (including disability), layoff, jury duty, military duty or leave of absence. Notwithstanding the preceding sentence,

   1. (i) No more than 501 hours of service are required to be credited under this paragraph (a)(2) to an employee on account of any single continuous period during which the employee performs no duties (whether or not such period occurs in a single computation period);
   2. (ii) An hour for which an employee is directly or indirectly paid, or entitled to payment, on account of a period during which no duties are performed is not required to be credited to the employee if such payment is made or due under a plan maintained solely for the purpose of complying with applicable workmen's compensation, or unemployment compensation or disability insurance laws; and

   3. (iii) Hours of service are not required to be credited for a payment which solely reimburses an employee for medical or medically related expenses incurred by the employee.

      For purposes of this paragraph (a)(2), a payment shall be deemed to be made by or due from an employer regardless of whether such payment is made by or due from the employer directly, or indirectly through, among others, a trust fund, or insurer, to which the employer contributes or pays premiums and regardless of whether contributions made or due to the trust fund, insurer or other entity are for the benefit of particular employees or are on behalf of a group of employees in the aggregate.

3. (3) An hour of service is each hour for which back pay, irrespective of mitigation of damages, is either awarded or agreed to by the employer. The same hours of service shall not be credited both under paragraph (a)(1) or paragraph (a)(2), as the case may be, and under this paragraph (a)(3). Thus, for example, an employee who receives a back pay award following a determination that he or she was paid at an unlawful rate for hours of service previously credited will not be entitled to additional credit for the same hours of service. Crediting of hours of service for back pay awarded or agreed to with respect to periods described in paragraph (a)(2) shall be subject to the limitations set forth in that paragraph. For example, no more than 501 hours of service are required to be credited for payments of back pay, to the extent that such back pay is agreed to or awarded for a period of time during which an employee did not or would not have performed duties.

(b) Special rule for determining hours of service for reasons other than the performance of duties. In the case of a payment which is made or due on account of a period during which an employee performs no duties, and which results in the crediting of hours of service under paragraph (a)(2) of this section, or in the case of an award or agreement for back pay, to the extent that such award or agreement is made with respect to a period described in paragraph (a)(2) of this section, the number of hours of service to be credited shall be determined as follows:

1. (1) Payments calculated on the basis of units of time.

   1. (i) Except as provided in paragraph (b)(3) of this section, in case of a payment made or due which is calculated on the basis of units of time, such as hours, days, weeks or months, the number of hours of service to be credited shall be the number of regularly scheduled working hours included in the units of time on the basis of which the payment is calculated. For purposes of the preceding sentence, in the case of an employee without a regular work schedule, a plan may provide for the calculation of the number of hours to be credited on the basis of a 40-hour workweek or an 8-hour workday, or may provide for such calculation on any reasonable basis which reflects the average hours worked by the employee, or by other employees in the same job classification, over a representative period of time, provided that the basis so used is consistently applied with respect to all employees within the same job classifications, reasonably defined. Thus, for example, a plan may not use a 40-hour workweek as a basis for calculating the number of hours of service to be credited for periods of paid absences for one employee while using an average based on hours worked over a representative period of time as a basis for such calculation for another, similarly situated employee.

   2. (ii) Examples. The following examples illustrate the rules in paragraph (b)(1) of this section without regard to paragraphs (b)(2) and (3).

      1. (A) Employee A was paid for 6 hours of sick leave at his normal hourly rate. The payment was therefore calculated on the basis of units of time (hours). A must, therefore, be credited with 6 hours of service for the 6 hours of sick leave.
      2. (B) Employee B was paid his normal weekly salary for 2 weeks of vacation. The payment was therefore calculated on the basis of units of time (weeks). B is scheduled to work 37 1/2 hours per week (although from time to time working overtime). B must, therefore, be credited with 75 hours of service for the vacation (37 1/2 hours per week multiplied by 2 weeks).
      3. (C) Employee C spent 3 weeks on a paid vacation. C's salary is established at an annual rate but is paid on a bi-weekly basis. The amount of salary payments attributable to be paid vacation was calculated on the basis of units of time (weeks). C has no regular work schedule but works at least 50 hours per week. The plan provides for the calculation of hours of service to be credited to employees in C's situation for periods of paid absences on the basis of a 40-hour workweek. C must, therefore, be credited with 120 hours of service for the vacation (3 weeks multiplied by 40 hours per week).
      4. (D) Employee D spent 2 weeks on vacation, for which he was paid $150. Although D has no regular work schedule, the $150 payment was established on the assumption that an employee in D's position works an average of 30 hours per week at a rate of $2.25 per hour. The payment of $150 was therefore calculated on the basis of units of time (weeks). The plan provides for the calculation of hours of service to be credited to employees in D's situation for periods of paid absences on the basis of the average number of hours worked by an employee over a period of 6 months. D's employer's records show that D worked an average of 28 hours per week for a 6-month period. D must, therefore, be credited with 56 hours of service for the vacation (28 hours per week multiplied by 2 weeks).
      5. (E) Employee E is regularly scheduled to work a 40-hour week. During a computation period E is incapacitated as a result of injury for a period of 11 weeks. Under the sick leave policy of E's employer E is paid his normal weekly salary for the first 8 weeks of his incapacity. After 8 weeks the employer ceases to pay E's normal salary but, under a disability insurance program maintained by the employer, E receives payments equal to 65% of his normal weekly salary for the remaining 3 weeks during which E is incapacitated. For the period during which he is incapacitated, therefore, E receives credit for 440 hours of service (11 weeks multiplied by 40 hours per week) regardless of the fact that payments to E for the last 3 wseeks of the period during which hs was incapacitated were made in amounts less than E's normal compensation.

2. (2) Payments not calculated on the basis of units of time.

   1. (i) Except as provided in paragraph (b)(3) of this section, in the case of a payment made or due, which is not calculated on the basis of units of time, the number of hours of service to be credited shall be equal to the amount of the payment divided by the employee's most recent hourly ratre of compensation (as determined under paragraph (b)(2)(ii) of this section) before the period during which no duties are performed.

   2. (ii) For purposes of paragraph (b)(2)(i) of this section an employee's hourly rate of compensation shall be determined as follows:

      1. (A) In the case of an employee whose compensation is determined on the basis of an hourly rate, such hourly rate shall be the employee's most recent hourly rate of compensation.
      2. (B) In the case of an employee whose compensation is determined on the basis of a fixed rate for specified periods of time (other than hours) such as days, weeks or months, the employee's hourly rate of compensation shall be the employee's most recent rate of compensation for a specified period of time (other than an hour), divided by the number of hours regularly scheduled for the performance of duties during such period of time. For purposes of the preceding sentence, in the case of an employee without a regular work schedule, the plan may provide for the calculation of the employee's hourly rate of compensation on the basis of a 40-hour workweek, an 8-hour workday, or may provide for such calculation on any reasonable basis which reflects the average hours worked by the employee over a representative period of time, provided that the basis so used is consistently applied with respect to all employees within the same job classifications, reasonably defined.
      3. (C) In the case of an employee whose compensation is not determined on the basis of a fixed rate for specified periods of time, the employee's hourly rate of compensation shall be the lowest hourly rate of compensation paid to employees in the same job classification as that of the employee or, if no employees in the same job classification have an hourly rate, the minimum wage as established from time to time under section 6(a)(1) of the Fair Labor Standards Act of 1938, as amended.

   3. (iii) Examples. The following examples illustrate the rules in paragraph (b)(2) of this section without regard to paragraphs (b)(1) and (3).

      1. (A) As a result of an injury, an employee is incapacitated for 5 weeks. A lump sum payment of $500 is made to the employee with respect to the injury under a disability insurance plan maintained by the employee's employer. At the time of the injury, the employee's rate of pay was $3.00 per hour. The employee must, therefore, be credited with 167 hours of service ($500 divided by $3.00 per hour).
      2. (B) Same facts as in Example (A), above, except that at the time of the injury, the employee's rate of pay was $160 per week and the employee has a regular work schedule of 40 hours per week. The employee's hourly rate of compensation is, therefore, $4.00 per hour ($160 per week divided by 40 hours per week) and the employee must be credited with 125 hours of service for the period of absence ($500 divided by $4.00 per hour).
      3. (C) An employee is paid at an hourly rate of $3.00 per hour and works a regular schedule of 40 hours per week. The employee is disabled for 26 weeks during a computation period. For the first 12 weeks of disability, the employee is paid his normal weekly earnings of $120 per week by the employer. Thereupon, a lump-sum disability payment of $1000 is made to the employee under a disability insurance plan maintained by the employer. Under paragraph (a)(3)(i) of this section, the employee is credited with 501 hours of service for the period of disability (lesser of 501 hours—the maximum number of hours required to be credited for a period of absence—or the sum of 12 weeks multiplied by 40 hours per week plus $1000 divided by $3.00 per hour).

3. (3) Rule against double credit.

   1. (i) Nothwithstanding paragraphs (b)(1) and (2) of this section, an employee is not required to be credited on account of a period during which no duties are performed with a number of hours of service which is greater than the number of hours regularly scheduled for the performance of duties during such period. For purposes of applying the preceding sentence in the case of an employee without a regular work schedule, a plan may provide for the calculation of the number of hours of service to be credited to the employee for a period during which no duties are performed on the basis of a 40-hour workweek or an 8-hour workday, or may provide for such calculation on any reasonable basis which reflects the average hours worked by the employee, or by other employees in the same job classification, over a representative period of time, provided that the basis so used is consistently applied with respect to all employees within the same job classifications, reasonably defined.

   2. (ii) Examples.

      1. (A) Employee A has a regular 40-hour workweek. Each year Employee A is entitled to pay for a two-week vacation, in addition to receiving normal wages for all hours worked, regardless of whether A actually takes a vacation and regardless of the duration of his vacation. The vacation payments are, therefore, calculated on the basis of units of time (weeks). In computation period I, A takes no vacation but receives vacation pay. A is entitled to no credit for hours of service for the vacation payment made in computation period I because the payment was not made on account of a period during which no duties were performed. In computation period II, A takes a vacation of one week in duration, although receiving pay for a two-week vacation. A is entitled to be credited with 40 hours of service for his one-week vacation in computation period II even though paid for two weeks of vacation. In computation period III, A takes a vacation for a period lasting more than 2 weeks. A is entitled to be credited with 80 hours of service for his vacation in computation period III (40 hours per week multiplied by 2 weeks) even though the vacation lasted more than 2 weeks.
      2. (B) Employee B has no regular work schedule. As a result of an injury, B is incapacitated for 1 day. A lump-sum payment of $500 is made to A with respect to the injury under an insurance program maintained by the employer. A pension plan maintained by the employer provides for the calculation of the number of hours of service to be credited to an employee without a regular work schedule on the basis of an 8-hour day. A is therefore required to be credited with no more than 8 hours for the day during which he was incapacitated, even though A's rate of pay immediately before the injury was $3.00 per hour.

(c) Crediting of hours of service to computation periods.

1. (1) Except as provided in paragraph (c)(4) of this section, hours of service described in paragraph (a)(1) of this section shall be credited to the computation period in which the duties are performed.

2. (2) Except as provided in paragraph (c)(4) of this section, hours of service described in paragraph (a)(2) of this section shall be credited as follows:

   1. (i) Hours of service credited to an employee on account of a payment which is calculated on the basis of units of time, such as hours, days, weeks or months, shall be credited to the computation period or computation periods in which the period during which no duties are performed occurs, beginning with the first unit of time to which the payment relates.
   2. (ii) Hours of service credited to an employee by reason of a payment which is not calculated on the basis of units of time shall be credited to the computation period in which the period during which no duties are performed occurs, or if the period during which no duties are performed extends beyond one computation period, such hours of service shall be allocated between not more than the first two computation periods on any reasonable basis which is consistently applied with respect to all employees within the same job classifications, reasonably defined.
3. (3) Except as provided in paragraph (c)(4) of this section, hours of service described in paragraph (a)(3) of this section shall be credited to the computation period or periods to which the award or agreement for back pay pertains, rather than to the computation period in which the award, agreement or payment is made.
4. (4) In the case of hours of service to be credited to an employee in connection with a period of no more than 31 days which extends beyond one computation period, all such hours of service may be credited to the first computation period or the second computation period. Crediting of hours of service under this paragraph must be done consistently with respect to all employees within the same job classifications, reasonably defined.

5. (5) Examples. The following examples are intended to illustrate paragraph (c)(4) of this section.

   1. (i) An employer maintaining a plan pays employees on a bi-weekly basis. The plan designates the calendar year as the vesting computation period. The employer adopts the practice of crediting hours of service for the performance of duties during a bi-weekly payroll period to the vesting computation period in which the payroll period ends. Thus, when a payroll period ends on January 7, 1978, all hours of service to be credited to employees for the performance of duties during that payroll period are credited to the vesting computation period beginning on January 1, 1978. This practice is consistent with paragraph (c)(4) of this section, even though some hours of service credited to the computation period beginning on January 1, 1978, are attributable to duties performed during the previous vesting computation period.
   2. (ii) An employer maintains a sick leave policy under which an employee is entitled to a certain number of hours of sick leave each year, on account of which the employee is paid his or her normal rate of compensation. An employee with a work schedule of 8 hours per day, 5 days per week, is sick from December 26, 1977 through January 4, 1978. Under the employer's sick leave policy, the employee is entitled to compensation for the entire period. A plan maintained by the employer establishes a calendar-year vesting computation period. The period from December 26, 1977 through December 31, 1977 includes 5 working days; the period from January 1, 1978 through January 4, 1978 includes 3 working days. Unless the plan adopts the alternative method for crediting service under paragraph (c)(4) of this section (illustrated in Example (iii), below) for the period of paid sick leave, the plan, pursuant to paragraph (c)(2)(i) of this section, must credit the employee with 40 hours of service in the 1977 vesting computation period (5 days multiplied by 8 hours per day) and 24 hours of service in the 1978 vesting computation period (3 days multiplied by 8 hours per day).
   3. (iii) Same facts as in Example (ii), above, except that the plan adopts the practice of crediting hours of service for sick leave and other periods of compensated absences to the vesting computation period in which the employer's bi-weekly payroll period ends. The employee returns to work on January 5, 1978 and works for 2 days. For the 2-week payroll period ending on January 8, 1978, the employee may be credited with 80 hours of service in the 1978 vesting computation period (64 hours of service for the paid sick leave and 16 hours of service for the 2 days during which duties were performed).

(e) Additional examples.

1. (1) During a computation period, an employee was paid for working 38 1/4 hours a week for 45 weeks. During the remaining 7 weeks of the computation period the employee was not employed by this employer. The employee completed 1,721 1/4 hours of service (45 weeks worked multiplied by 38 1/4 hours per week). The employer may also round up hours at the end of the computation period or more frequently. Thus, this employee could be credited with 1,722 hours of service (or, if the employer rounded up at the end of each week, 39 hours of service per week, resulting in credit for 1,755 hours of service).
2. (2) During a computation period, an employee was paid for a workweek of 40 hours per week for 40 weeks and, including overtime, for working 50 hours per week for 8 weeks. The employee completed 2,000 hours of service (40 weeks multiplied by 40 hours per week, plus 8 weeks worked multiplied by 50 hours per week).
3. (3) During a computation period an employee was paid for working 2 regularly scheduled 40-hour weeks and then became disabled. The employee was disabled through the remainder of the computation period and the following computation period. Throughout the period of disability, payments were made to the employee as follows: For the first month of the period of disability, the employer continued to pay the employee the employee's normal compensation at the same rate as before the disability occurred; thereupon, under the employer's disability insurance policy, payments were made to the employee in amounts equal to 80 percent of the employee's compensation before the disability. For the first computation period the employee is credited with 80 hours of service for the performance of duties (2 weeks multiplied by 40 hours per week) and 501 hours hours of service for the period of disability (the lesser of 501 hours of service or 50 weeks multiplied by 40 hours per week), or a total of 581 hours of service; for the second computation period the employee is credited with no hours of service because, under paragraph (a)(2)(i) of this section, the maximum of 501 hours of service has been credited for the period of disability in the first computation period.
4. (4) An employee has a regularly scheduled 5-day, 40-hour week. During a computation period the employee works for the first week, spends the second week on a paid vacation, returns to work for an hour and is then disabled for the remainder of the computation period. Payments under a disability plan maintained by the employer are made to the employee on account of the period of disability. The employee is credited with 582 hours of service for the computation period (40 hours for the period of paid vacation; 41 hours for the performance of duties; 501 hours for the period of disability).
5. (5) Same facts as in Example (4), above, except that the employee's period of disability begins before the employee returns from vacation to the performance of duties. The employee is credited with only 541 hours of service, because the paid vacation and the disability together constitute a single, continuous period during which no duties were performed and, therefore, under paragraph (a)(2)(i) of this section, no more than 501 hours of service are required to be credited for such period.
6. (6) During a computation period, an employee worked 40 hours a week for the first 2 weeks. The employee then began serving on active duty in the Armed Forces of the United States, which service occupied the remaining 50 weeks of the computation period. The employee would be credited with 80 hours (2 weeks worked multiplied by 40 hours) plus such credit as may be prescribed by separate Federal laws relating to military service. The nature and extent of the credit that the employee receives upon his return and the purpose for which such credit is given, e.g., the percentage of his or her accrued benefits derived from employer contributions which are nonforfeitable (or vested), will depend upon the interpretation of the Federal law governing veterans' reemployment rights.