12.4 Applying the Plan's Compensation Definition: Components, Payroll Mapping & Common Administrative Errors

Key Takeaways

  • The single most common operational failure in the EPCRS catalogue is using an incorrect definition of compensation, usually because a payroll code was never mapped to the plan's definition.
  • Post-severance compensation for regular pay, overtime and commissions is included in IRC §415 compensation if paid by the later of 2½ months after severance or the end of the limitation year; true severance pay is always excluded.
  • A plan may use different compensation definitions for deferrals, match, profit sharing, and testing, and administrators must confirm which definition governs each calculation before running any allocation.
  • The standard EPCRS correction for a missed deferral opportunity caused by excluding eligible compensation is a qualified nonelective contribution equal to 50% of the missed deferral, reduced to 25% under the safe harbor for automatic contribution arrangements, plus 100% of the missed match, adjusted for earnings.
Last updated: September 2026

Where the Errors Actually Happen

Compensation is only 8% of the QKA-2 exam, but it is the number one source of operational failures in practice, and the exam reflects that by testing the application rather than the recitation. Nearly every failure has the same shape: the document says one thing and the payroll file says another. A new pay code — a retention bonus, a car allowance, a shift differential — gets created in payroll and nobody maps it to the plan's definition.

One Plan, Several Definitions

A single document routinely carries four compensation definitions, and the administrator must know which governs which calculation:

PurposeTypical definitionWhy
Deferral base"Plan compensation" — often W-2 pay with exclusionsWhat the participant's election percentage is applied to
Match baseFrequently the same as the deferral baseMust satisfy §414(s) if the match is a safe harbor
Allocation base (profit sharing)Often full §415 compensationSimplifies §401(a)(4) testing
Testing baseMust satisfy IRC §414(s)ADP/ACP, coverage, §401(a)(4), gateway
Limit baseIRC §415 compensation — no exclusions permitted§415(c), HCE determination, key employee determination, top-heavy

The critical discipline: §415 compensation cannot be modified. A plan may exclude bonuses from the deferral base, but it may not exclude bonuses when testing whether a participant exceeded the §415(c) annual additions limit, when determining HCE status under §414(q), or when identifying key employees under §416.

Mapping Payroll Components

Payroll component§415 compensation?Typically in plan compensation?
Base salary and wagesYesYes
OvertimeYesYes, unless expressly excluded
CommissionsYesYes, unless expressly excluded
BonusesYesYes, unless expressly excluded
Shift differentials, on-call payYesYes
Taxable fringe benefits (personal use of company car, group term life over $50,000)YesOften excluded
Taxable moving expense reimbursementsYesOften excluded
Elective deferrals to 401(k), 125 cafeteria, 132(f) transitYes — added back under §415(c)(3)(D)Yes
Non-taxable employer health premiumsNoNo
Severance payNo — neverNo
Distributions from a nonqualified deferred compensation planNo (unless paid within the post-severance window and includible)No
Workers' compensation, disability payments from a third partyNoNo
Deemed §125 compensation (cafeteria plan cash-out unavailable without health coverage proof)Yes, if the plan so providesPer document

The single largest practical trap: elective deferrals themselves. A participant earning $100,000 who defers $10,000 has $100,000 of §415 compensation, not $90,000. Deferrals are added back. Candidates who use the W-2 Box 1 figure without the add-back understate compensation on every calculation that follows.

Post-Severance Compensation Timing

Under Treas. Reg. §1.415(c)-2(e)(3), amounts paid after severance from employment are included in §415 compensation only if paid by the later of:

  • 2½ months after severance from employment, or
  • the end of the limitation year that includes the date of severance,

and the payment is one of the following:

Post-severance payment typeIncluded?
Regular pay for services rendered before severanceYes
Overtime, shift differential, commissions, bonuses for pre-severance servicesYes
Payment for accrued unused sick, vacation or other leave the employee could have used if employment continuedYes, if the plan so provides
Nonqualified deferred compensation that would have been paid regardless of severanceYes, if the plan so provides and it is includible in income
Severance pay / parachute paymentsNo — never, regardless of timing
Payments made after the later of the two deadlinesNo

Worked example. Marcus severs employment on November 20, 2026 from a calendar-year plan. The limitation year ends December 31, 2026; 2½ months after severance is February 4, 2027. The later of the two is February 4, 2027.

PaymentDateIn §415 comp?
Final regular paycheck, $6,20011/30/2026Yes
Q4 sales commission earned pre-severance, $18,00001/15/2027Yes — before 2/4/2027
Accrued unused vacation payout, $4,40001/15/2027Yes, if the plan so provides
Discretionary annual bonus for 2026, $12,00003/10/2027No — after 2/4/2027
Severance package, $30,00012/05/2026No — severance pay is never included

Partial Year of Participation

When an employee enters mid-year, the plan may measure compensation either for the full plan year or only for the period of participation. The choice must be applied uniformly, and it matters enormously in testing:

  • Using period-of-participation compensation raises a mid-year entrant's deferral percentage in the ADP test (a smaller denominator), which usually helps the NHCE average.
  • The §401(a)(17) limit is prorated only for a short plan year, never for a short period of participation. An employee who enters July 1 of a calendar-year plan is still subject to the full $360,000 limit for 2026.

That distinction — prorate for a short plan year, never for a short participation period — is a reliable exam item.

Correcting a Wrong-Compensation Failure

When the plan used the wrong definition and under-contributed, EPCRS supplies the correction:

ElementCorrection
Missed deferral opportunityA QNEC equal to 50% of the missed deferral (the participant's actual deferral rate applied to the omitted compensation)
Same, under an automatic contribution arrangement safe harbor25%, or 0% if the failure is caught and corrected quickly and notice is given, under the SECURE 2.0 §350 self-correction rules
Missed matching contribution100% of the match the participant would have received
EarningsRequired on all corrective amounts, from the date of the failure
Missed non-elective allocation100% of the missed allocation, plus earnings

The QNEC is 50% of the missed deferral because Congress and the IRS treat the participant as having lost only the opportunity, not the money itself — the participant keeps the cash they would have deferred. The match is 100% because that is money the participant never had any claim on otherwise.


Common ASPPA QKA Exam Traps

  • Trap 1 — Forgetting the deferral add-back. §415 compensation includes elective deferrals; W-2 Box 1 does not.
  • Trap 2 — Including severance pay. It is excluded from §415 compensation in every circumstance.
  • Trap 3 — Getting the post-severance window backwards. It is the later of 2½ months or the end of the limitation year.
  • Trap 4 — Prorating §401(a)(17) for mid-year entry. Prorate only for a short plan year.
  • Trap 5 — Applying a modified definition to §415, HCE, or key employee determinations. Those always use unmodified §415 compensation.
  • Trap 6 — Using 100% for the missed deferral QNEC. It is 50% (25% for ACA designs); the match is what gets 100%.
Test Your Knowledge

Marcus severs employment on November 20, 2026 from a calendar-year plan. Which payment is included in his IRC §415 compensation?

A
B
C
D
Test Your Knowledge

A participant earning $100,000 defers $10,000 to the 401(k) plan. What is the participant's IRC §415 compensation?

A
B
C
D
Test Your Knowledge

A plan excluded a newly created bonus pay code from plan compensation contrary to the document, causing a participant who defers 6% to miss deferrals on $20,000 of bonus pay. The plan also provides a 50% match on the first 6%. What is the EPCRS correction?

A
B
C
D