15.4 Otherwise Excludable Employees: When Disaggregation Rescues a Failing Test

A Reward for Generosity

IRC §410(a) lets a plan impose a maximum eligibility condition of age 21 and one year of service. Many sponsors are more generous — immediate entry, or three months, or six months — for recruiting reasons. Without relief, that generosity would be punished: all those short-service, low-deferring NHCEs would flood the testing group and drag down both coverage and the ADP test.

IRC §410(b)(4)(B) supplies the relief. A plan whose eligibility is more liberal than the statutory maximum may be treated as two separate plans:

1. The statutory group — employees who have met age 21 and one year of service.
2. The otherwise excludable group — employees who have not met that statutory standard but are eligible under the plan's more generous terms.

Each group is then tested for §410(b) coverage separately, and each must pass on its own.

Critical framing: the split is measured against the statutory standard (age 21, one year), never against the plan's actual terms. A plan with three-month eligibility has an otherwise excludable group consisting of everyone with under one year of service or under age 21.

When Disaggregation Helps

The election is beneficial when the otherwise excludable group contains few or no HCEs. Because a plan benefiting no HCEs is deemed to satisfy coverage, the otherwise excludable "plan" passes automatically, and the statutory group — now free of dozens of non-benefiting or low-deferring short-service NHCEs — is tested on its own, usually with far better numbers.

Worked example — coverage rescued. Harbor Point Design has immediate eligibility and a last-day allocation condition on its profit-sharing contribution.

Combined testing (no disaggregation):

Group	Total	Benefiting	Benefiting %
HCEs	6	6	100.0%
NHCEs	74	46	62.2%

Ratio percentage = 62.2 ÷ 100.0 = 62.2% — fails the 70% ratio percentage test.

After disaggregation. Of the 74 NHCEs, 26 have under one year of service; 8 of those benefit. All 6 HCEs have long service.

Statutory group:

Group	Total	Benefiting	Benefiting %
HCEs	6	6	100.0%
NHCEs	48	38	79.2%

Ratio percentage = 79.2 ÷ 100.0 = 79.2% — passes.

Otherwise excludable group: 0 HCEs, 26 NHCEs, 8 benefiting. The group benefits no HCEs, so it is deemed to pass.

Both disaggregated plans pass. The election converted a failure into a pass without the employer contributing an additional dollar.

When Disaggregation Hurts

The election is not automatically beneficial, and the exam tests the reverse case. Disaggregation backfires when HCEs sit in the otherwise excludable group — most commonly a newly hired owner's child, a recently hired executive, or a new partner.

Counter-example. Suppose Harbor Point hires the owner's daughter, an HCE by attribution, in September. She is in the otherwise excludable group and benefits. That group now has 1 of 1 HCEs benefiting (100%) and 8 of 26 NHCEs benefiting (30.8%). Ratio percentage = 30.8 ÷ 100.0 = 30.8% — the otherwise excludable group now fails badly, and because each disaggregated plan must pass on its own, the election has manufactured a failure. Testing on a combined basis would have been the better choice.

The administrator's rule: run the test both ways before electing. Disaggregation is an option, not a requirement, and it may be elected or not elected on a year-by-year basis.

The Parallel Benefit in ADP and ACP Testing

The same disaggregation is available for ADP and ACP testing under Treas. Reg. §1.401(k)-1(b)(4)(iv), and this is frequently where it is worth the most. Newly eligible short-service employees defer at very low rates, and every eligible non-deferrer enters the ADP calculation at 0.00%.

Worked example — ADP rescued. Harbor Point's 2026 ADP results:

Population	Count	ADP
HCEs	6	7.10%
All NHCEs (combined)	74	3.05%
NHCEs with 1+ year of service	48	4.42%
NHCEs with under 1 year	26	0.52%

Combined test: NHCE ADP 3.05% → maximum HCE ADP under the 2%-spread rule = 5.05%. The HCE ADP of 7.10% fails, generating refunds.

Disaggregated test: the statutory group's NHCE ADP is 4.42% → maximum HCE ADP = 6.42%. Still short of 7.10%, but the excess is far smaller, so refunds shrink substantially. If the HCE ADP had been 6.20%, disaggregation alone would have converted a failure into a pass.

The otherwise excludable group is tested separately: 0 HCEs eligible in that group means it is deemed to pass.

Rules and Limits on the Election

---

Common ASPPA QKA Exam Traps

• Trap 1 — Splitting on the plan's own eligibility terms. The otherwise excludable group is defined by the statutory age 21 / one-year standard.
• Trap 2 — Assuming the election always helps. If an HCE lands in the otherwise excludable group, it can create a failure.
• Trap 3 — Testing only the statutory group. Both disaggregated groups must pass independently.
• Trap 4 — Believing it is a permanent election. It is generally an annual testing choice.
• Trap 5 — Forgetting the deemed-pass interaction. An otherwise excludable group with no benefiting HCEs passes automatically, which is the whole point of the strategy.
• Trap 6 — Overlooking LTPT employees. Long-term part-time employees eligible solely under the 500-hour rule are excluded from coverage, ADP/ACP, and top-heavy testing by statute, which is a separate and additional relief.