(a) General rule. For the purpose of determining the hours of service which must be credited to an employee for a computation period, a plan shall determine hours of service from records of hours worked and hours for which payment is made or due or shall use an equivalency permitted under paragraph (d), (e) or (f) of this section to determine hours of service. Any records may be used to determine hours of service to be credited to employees under a plan, even though such records are maintained for other purposes, provided that they accurately reflect the actual number of hours of service with which an employee is required to be credited under § 2530.200b-2(a). Payroll records, for example, may provide sufficiently accurate data to serve as a basis for determining hours of service. If, however, existing records do not accurately reflect the actual number of hours of service with which an employee is entitled to be credited, a plan must either develop and maintain adequate records or use one of the permitted equivalencies. A plan may in any case credit hours of service under any method which results in the crediting of no less than the actual number of hours of service required to be credited under § 2530.200b-2(a) to each employee in a computation period, even though such method may result in the crediting of hours of service in excess of the number of hours required to be credited under § 2530.200b-2. A plan is not required to prescribe in its documents which records are to be used to determine hours of service.

(b) Determination of pre-effective date hours of service. To the extent that a plan is required to determine hours of service completed before the effective date of part 2 of title I of the Act (see section 211 of the Act), the plan may use whatever records may be reasonably accessible to it and may make whatever calculations are necessary to determine the approximate number of hours of service completed before such effective date. For example, if a plan or an employer maintaining the plan has, or has access to, only the records of compensation of employees for the period before the effective date, it may derive the pre-effective date hours of service by using the hourly rate for the period or the hours customarily worked. If accessible records are insufficient to make an approximation of the number of pre-effective date hours of service for a particular employee or group of employees, the plan may make a reasonable estimate of the hours of service completed by such employee or employees during the particular period. For example, if records are available with respect to some employees, the plan may estimate the hours of other employees in the same job classification based on these records. A plan may use any of the equivalencies permitted under this section, or the elapsed time method of crediting service permitted under this section, or the elapsed time method of crediting service permitted under § 2530.200b-9, to determine hours of service completed before the effective date of part 2 of title I of the Act.

(c) Use of equivalencies for determining service to be credited to employees. (1) The equivalencies permitted under paragraphs (d), (e) and (f) of this section are methods of determining service to be credited to employees during computation periods which are alternatives to the general rule for determining hours of service set forth in paragraph (a) of this section. The equivalencies are designed to enable a plan to determine the amount of service to be credited to an employee in a computation period on the basis of records which do not accurately reflect the actual number of hours of service required to be credited to the employee under § 2530.200b-2(a). However, the equivalencies may be used even if such records are maintained. Any equivalency used by a plan must be set forth in the document under which the plan is maintained.

(2) A plan may use different methods of crediting service, including equivalencies permitted under paragraphs (d), (e) and (f) of this section and the method of crediting service under the general rule set forth in § 2530.200b-2(a), for different classifications of employees covered under the plan or for different purposes, provided that such classifications are reasonable and are consistently applied. Thus, for example, a plan may provide that part-time employees are credited under the general method of crediting service set forth in § 2530.200b-2 and full-time employees are credited under a permissible equivalency. A classification, however, will not be deemed to be reasonable or consistently applied if such classification is designed with an intent to preclude an employee or employees from attaining statutory entitlement with respect to eligibility to participate, vesting or benefit accrual. For example, a classification applied so that any employee credited with less than 1,000 hours of service during a given 12-consecutive-month period would be considered part-time and subject to the general method of crediting service rather than an equivalency would not be reasonable.

(3) Notwithstanding paragraphs (c)(1) and (2) of this section, the use of a permissible equivalency for some, but not all, purposes or the use of a permissible equivalency for some, but not all, employees may, under certain circumstances, result in discrimination prohibited under section 401a of the Code, even though it is permitted under this section.

(d) Equivalencies based on working time—(1) Hours worked. A plan may determine service to be credited to an employee on the basis of hours worked, as defined in paragraph (d)(3)(i) of this section, if 870 hours worked are treated as equivalent to 1,000 hours of service and 435 hours worked are treated as equivalent to 500 hours of service.

(2) Regular time hours. A plan may determine service to be credited to an employee on the basis of regular time hours, as defined in paragraph (d)(3)(ii) of this section, if 750 regular time hours are treated as equivalent to 1,000 hours of service and 375 regular time hours are treated as equivalent to 500 hours of service.

(3) For purposes of this section:

(i) The term “hours worked” shall mean hours of service described in § 2530.200b-2(a)(1), and hours for which back pay, irrespective of mitigation of damages, is awarded or agreed to by an employer, to the extent that such award or agreement is intended to compensate an employee for periods during which the employee would have been engaged in the performance of duties for the employer.

(ii) The term “regular time hours” shall mean hours worked, except hours for which a premium rate is paid because such hours are in excess of the maximum workweek applicable to an employee under section 7(a) of the Fair Labor Standards Act of 1938, as amended, or because such hours are in excess of a bona fide standard workweek or workday.

(4) A plan determining service to be credited to an employee on the basis of hours worked or regular time hours shall credit hours worked or regular time hours, as the case may be, to computation periods in accordance with the rules for crediting hours of service to computation periods set forth in § 2530.200b-2(c).

(5) Examples. (i) A defined benefit plan uses the equivalency based on hours worked permitted under paragraph (d)(1) of this section. The plan uses the same 12-consecutive-month period for the vesting and accrual computation periods. The plan credits a participant with each hour for which the participant is paid, or entitled to payment, for the performance of duties for the employer during a computation period (as well as each hour for which back pay is awarded or agreed to). During a vesting/accrual computation period Participant A is credited with 870 hours worked. A is credited with a year of service for purposes of vesting for the computation period and with at least a partial year of participation for purposes of accrual, as if A had been credited with 1000 hours of service during the computation period. During the same computation period Participant B is credited with 436 hours of service. B is not credited with a year of service for purposes of vesting or a partial year or paritcipation for purposes of accrual for the computation period, but does not incur a one-year break in service for the computation period, as if B had been credited with 501 hours of service during the computation period.

(ii) A plan uses the equivalency based on regular time hours permitted under paragraph (d)(2) of this section. During a computation period a participant works 370 regular time hours and 20 overtime hours. The participant incurs a one-year break in service for the computation period because he has not been credited with 375 regular time hours in the computation period.

(e) Equivalencies based on periods of employment. (1) Except as provided in paragraphs (e)(4) and (6) of this section, a plan may determine the number of hours of service to be credited to employees in a computation period on the following bases:

(i) On the basis of days of employment, if an employee is credited with 10 hours of service for each day for which the employee would be required to be credited with at least one hour of service under § 2530.200b-2;

(ii) On the basis of weeks of employment, if an employee is credited with 45 hours of service for each week for which the employee would be required to be credited with at least one hour of service under § 2530.200b-2;

(iii) On the basis of semi-monthly payroll periods, if an employee is credited with 95 hours of service for each semi-monthly payroll period for which the employee would be required to be credited with at least one hour of service under § 2530.200b-2; or

(iv) On the basis of months of employment, if an employee is credited with 190 hours of service for each month for which the employee would be required to be credited with at least one hour of service under § 2530.200 b-2.

(2) Except as provided in paragraphs (e)(4) and (6) of this section, a plan may determine the number of hours of service to be credited to employees in a computation period on the basis of shifts if an employee is credited with the number of hours included in a shift for each shift for which the employee would be required to be credited with at least one hour of service under § 2530.200b-2. if a plan uses the equivalency based on shifts permitted under this paragraph, the times of the beginning and end of each shift used as a basis for the determination of service shall be set forth in a document referred to in the plan.

(3) Examples. The following examples illustrate the application of paragraphs (e)(1) and (2) of this section;

(i) A plan uses the equivalency based on weeks of employment permitted under paragraph (e)(1)(ii) of this section. An employee works for one hour on the first workday of a week and then takes leave without pay for the entire remainder of the week. The plan must credit the employee with 45 hours of service for the week.

(ii) A plan uses the equivalency based on weeks of employment permitted under paragraph (e)(1)(ii) of this section. An employee spends a week on vacation with pay. The plan must credit the employee with 45 hours of service for the week.

(iii) A plan uses the equivalency based on weeks of employment permitted under paragraph (e)(1)(ii) of this section. An employee spends two days of a week on vacation with pay and the remainder of the week on leave without pay. The plan must credit the employee with 45 hours of service for the week.

(iv) A plan uses the equivalency based on weeks of employment permitted under paragraph (e)(1)(ii) of this section. An employee spends the entire week on leave without pay. The plan is not required to credit the employee with any hours of service for the week because no payment was made to the employee for the week of leave and, therefore, under § 2530.200b-2 no hours of service would be credited to the employee for the week of leave.

(v) The workday of an employer maintaining a plan is scheduled in shifts. Ordinarily, each shift is 6 hours in duration. At certain times, however, the employer schedules 8-hour shifts in order to meet increased demand. Such shifts are described in a collective bargaining agreement referred to in the plan documents. The plan must credit an employee with 6 hours of service for each 6-hour shift for which the employee would be credited with one hour of service under § 2530.200b-2, and with 8 hours of service for each such 8-hour shift.

(vi) An employer's workday is divided into three 8-hour shifts, each employee generally working 5 shifts per week. A plan maintained by the employer uses the equivalency based on shifts permitted under paragraph (e)(2) of this section. An employee is on vacation with pay for 2 weeks, during which, in the ordinary course of his work schedule, he would have worked 10 shifts. The employee must be credited with 80 hours of service for the vacation (10 shifts multiplied by 8 hours per shift).

(vii) An employer's workday is divided into three 8-hour shifts, each employee generally working 1 shift per workday. A plan maintained by the employer uses the equivalency based on shifts permitted under paragraph (e)(2) of this section. On a certain day, an employee works his normal 8-hour shift and an hour during the following shift. In addition to 8 hours service for the first shift, the employee must be credited with 8 hours of service for the following shift, since he would be entitled to be credited with at least one hour of service for the second shift under § 2530.200b-2.

(viii) A plan uses the equivalency based on days permitted under paragraph (e)(1)(i) of this section. During a computation period an employee spends 2 weeks on vacation with pay. In the ordinary course of the employee's regular work schedule, the employee would be engaged in the performance of duties for 10 days during the 2-week vacation period. Under § 2530.200b-2, the employee would be credited with at least one hour of service for each of the 10 days during the 2-week vacation for which the employee would ordinarily be engaged in the performance of duties. Under paragraph (e)(4) of this section, the employee is credited with 100 hours of service for the 2-week vacation (10 days multiplied by 10 hours of service per day).

(4) For purposes of this paragraph, in the case of a payment described in § 2530.200b-2(b)(2) (relating to payments not calculated on the basis of units of time), a plan using an equivalency based on units of time permitted under this paragraph shall credit the employee with the number of hours of service determined under paragraph (2) of § 2530.200b-2(b), and, to the extent applicable, paragraph (e)(3), containing the rule against double crediting, of § 2530.200b-2(b). For example, if an employee with a regular work schedule of 40 hours per week paid at a rate of $3.00 per hour is incapacitated for a period of 4 weeks and receives a lump sum payment of $500 for his incapacity, the employee must be credited with 160 hours of service for the period of incapacity, regardless of whether the plan uses an equivalency permitted under this paragraph (see example at § 2530.200b-2(b)(2)(iii)(A). If, however, the employee is incapacitated for only 3 weeks, under § 2530.200b-2(b)(3) the emmployee is not required to be credited with more than 120 hours of service (lesser of 167 hours of service determined under the preceding sentence or 3 weeks multiplied by 40 hours per week).

(5) For purposes of this paragraph, in the case of a payment to an employee calculated on the basis of units of time which are greater than the periods of employment used by a plan as a basis for determining service to be credited to the employee under this paragraph, the plan shall credit the employee with the number of periods of employment which, in the course of the employee's regular work schedule, would be included in the unit or units of time on the basis of which the payment is calculated. For example, a plan uses the equivalency based on days permitted under paragraph (e)(1)(i) of this section. During a computation period an employee spends 2 weeks on vacation with pay. In the ordinary course of the employee's regular work schedule, the employee would be engaged in the performance of duties for 10 days during the 2-week vacation period. Under § 2530.200b-2, the emplopyee would be credited with at least one hour of service for each of the 10 days during the 2-week vacation for which the employee would ordinarily be engaged in the performance of duties. Under this paragraph the employee is credited with 100 hours of service for the 2-week vacation (10 days multiplied by 10 hours of service per day). If, however, the employee, although paid for a 2-week vacation, spends only one week on vacation, under § 2530.200b-2(b)(3) the employee is not required to be credited with more than 50 hours of service (5 days multiplied by 10 hours per day).

(6) For purposes of this paragraph, in the case of periods of time used as a basis for determining service to be credited to an employee which extend into two computation periods, the plan may credit all hours of service (or other units of service) credited for such a period to the first computation period or the second computation period, or may allocate such hours of service (or other units of service) between the two computation periods on a pro rata basis. Crediting of service under this paragraph must be done consistently with respect to all employees within the same job classifications, reasonably defined.

(7) A plan may combine an equivalency based on working time permitted under paragraph (d) of this section (i.e., hours worked or regular time hours) with an equivalency based on periods of employment permitted under this paragraph if the following conditions are met:

(i) The plan credits an employee with the number of hours worked or regular time hours, as the case may be, equal to the number of hours of service which would be credited to the employee under paragraphs (e)(1) and (2) of this section, for each period of employment for which the employee would be credited with one hour worked or one regular time hour; and

(ii) The plan treats hours worked and regular time hours in the manner prescribed under paragraphs (d)(1) and (2) of this section.

(8) Example. The following example illustrates the application of paragraph (e)(7) of this section. A plan uses the equivalency based on weeks of employment permitted under paragraph (e)(1)(ii) of this section in conjunction with the equivalency based on hours worked permitted under paragraph (d)(1) of this section, as provided in paragraph (e)(7) of this section. During a vesting computation period an employee is paid for the performance of duties for at least 1 hour in each of the first 20 weeks of the computation period and spends the next 2 weeks on a paid vacation. The employee thereupon terminates employment performing no further duties for the employer, and receiving no further compensation in the computation period. The employee is therefore credited with 900 hours worked for the vesting computation period (20 weeks multiplied by 45 hours per week), receiving no credit for the two weeks of paid vacation. The employee is credited with a year of service for the vesting computation period because he has been credited with more than 870 hours for the computation period.

(f) Equivalencies based on earnings. (1) In the case of an employee whose compensation is determined on the basis of an hourly rate, a plan may determine the number of hours to be credited the employee in a computation period on the basis of earnings, if:

(i) The employee is credited with the number of hours equal to the total of the employee's earnings from time to time during the computation period divided by the employee's hourly rate as in effect at such times during the computation period, or equal to the employee's total earnings for the performance of duties during the computation period divided by the employee's lowest hourly rate of compensation during the computation period, or by the lowest hourly rate of compensation payable to an employee in the same, or a similar job classification, reasonably defined; and

(ii) 870 hours credited under paragraph (f)(1)(i) of this section are treated as equivalent to 1,000 hours of service, and 435 hours credited under paragraph (f)(1)(i) of this section are treated as equivalent to 500 hours of service.

(2) In the case of an employee whose compensation is determined on a basis other than an hourly rate, a plan may determine the number of hours to be credited to the employee in a computation period on the basis of earnings if:

(i) The employee is credited with the number of hours equal to the employee's total earnings for the performance of duties during the computation period divided by the employee's lowest hourly rate of compensation during the computation period, determined under paragraph (f)(3) of this section; and

(ii) 750 hours credited under paragraph (f)(2)(i) of this section are treated as equivalent to 1,000 hours of service, and 375 hours credited under paragraph (f)(2)(i) of this section are treated as equivalent to 500 hours of service.

(3) For purposes of paragraph (f)(2) of this section, an employee's hourly rate of compensation shall be determined as follows:

(i) In the case of an employee whose compensation is determined on the basis of a fixed rate for a specified period of time (other than an hour) such as a day, week or month, the employee's hourly rate of compensation shall be the employee's lowest rate of compensation during a computation period for such specified period of time 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 or 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 to all employees within the same job classifications, reasonably defined.

(ii) In the case of an employee whose compensation is not determined on the basis of a fixed rate for a specified period of time, the employee's hourly rate of compensation shall be the lowest hourly rate of compensation payable to employees in the same job classification as 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.

(4) Examples. (i) In a particular job classification employees' wages range from $3.00 per hour to $4.00 per hour. To determine the number of hours to be credited to an employee in that job classification who is compensated at a rate of $4.00 per hour, a plan may divide the employee's total earnings during the computation period for the performance of duties either by $3.00 per hour (the lowest hourly rate of compensation in the job classification) or by $4.00 per hour (the employee's own hourly rate of compensation).

(ii) An hourly employee's total earnings for the performance of duties during a vesting computation period amount to $4,350. During that calendar year, the employee's lowest hourly rate of compensation was $5.00 per hour. The plan may determine the number of hours to be credited to the employee for that vesting computation period by dividing $4,350 by $5.00 per hour. The employee is credited with 870 hours for the vesting computation period and is, therefore, credited with a year of service for purposes of vesting.

(iii) During the first 3 months of a vesting computation period an hourly employee is paid at a rate of $3.00 per hour and earns $675 for the performance of duties; during the next 6 months, the employee is paid at a rate of $3.50 per hour and earns $1,575 for the performance of duties; during the final 3 months the employee is paid at a rate of $3.60 per hour and earns $810 for the performance of duties. The plan may determine the number of hours to be credited to the employee in the computation period under the equivalency set forth in paragraph (f)(1) of this section either (A) by dividing the employee's earnings for each period during which the employee was paid at a separate rate ($675 divided by $3.00 per hour equals 225 hours; $1,575 divided by $3.50 per hour equals 450 hours; $810 divided by $3.60 per hour equals 225 hours) and adding the hours so obtained (900 hours), or (B) by dividing the employee's total compensation for the vesting computation period by the employee's lowest hourly rate during the computation period ($3,020 divided by $3.00 per hour equals 1,009 2/3 hours). The plan may also divide the employee's total compensation during the computation period by the lowest hourly rate payable to an employee in the same, or a similar, job classification.

(iv) During a plan's computation period an hourly employee's total earnings for the performance of duties consist of $7,500 at a basic rate of $5.00 per hour and $750 at an overtime rate of $7.50 per hour for hours worked in excess of 40 in a week. If the plan uses the equivalency permitted under paragraph (f)(1) of this section, the plan may adjust for the overtime rate in calculating the number of hours to be credited to the employee. Thus, the plan may calculate the number of hours to be credited to the employee by adding the employee's earnings at the basic rate divided by the basic rate and the employee's earnings at the overtime rate divided by the overtime rate ($7,500 divided by $5.00 per hour, plus $750 divided by $7.50 per hour, or 1,500 hours plus 100 hours), resulting in credit for 1,600 hours for the computation period.

(v) During a plan's vesting computation period an employee's lowest weekly rate of compensation is $400 per week. The employee has a regular work schedule of 40 hours per week. The employee's lowest hourly rate during the vesting computation period is, therefore, $10 per hour ($400 per week divided by 40 hours per week). During the vesting computation period, the employee receives a total of $7,500 for the performance of duties. The plan determines the number of regular time hours to be credited to the employee for the computation period by dividing $7,500 by $10 per hour. The employee is credited with 750 hours for the computation period and is, therefore, credited with a year of service for purposes of vesting.