How Much Can You Actually Contribute to Your 401(k)? The Airline Pilot §415(c) Deferral Room Calculator

Generic advice says you can defer $24,500 into your 401(k) in 2026. For most airline pilots — especially mainline captains — that's wrong. Your airline is already depositing a large unconditional NEC (non-elective contribution) into your 401(k) account. Delta, United, American, and Southwest each contribute 18–22% of eligible compensation annually. At a captain salary of $350,000+, that employer deposit can consume most or all of your §415(c) annual additions bucket before you contribute a single dollar.

The §415(c) limit caps total contributions from all sources to one plan — employer plus employee — at $72,000 for 2026. Once the employer fills that bucket, your room for employee deferrals shrinks. This calculator shows you exactly what your picture looks like in 2026 based on your specific salary, carrier, and age.

How the §415(c) limit works for airline pilots

IRC §415(c) caps the total annual additions to a defined-contribution plan from all sources — employer contributions, employee deferrals, after-tax contributions — at the lesser of $72,000 or 100% of compensation for 2026.¹ Every dollar your airline deposits as a non-elective contribution (NEC) counts against that limit first, because the plan documents deposit NEC before processing employee elections.

For pilots at low-NEC carriers like FedEx (9%), the squeeze never materializes — $360,000 eligible comp × 9% = $32,400 employer NEC, leaving $39,600 of employee deferral room (far more than the $24,500 employee limit). For a Delta, United, or American captain making $380,000+, the arithmetic flips: the employer deposit alone can exceed $64,000, leaving less than $8,000 for employee deferrals.

The compensation cap most pilots miss

§401(a)(17) caps the compensation used to calculate employer contributions at $360,000 for 2026.² A captain earning $500,000 doesn't receive NEC on the full $500,000 — the NEC calculation uses $360,000. This actually helps high earners: without the cap, the employer NEC at 18% would be $90,000, which would exceed the §415(c) limit entirely. With the cap, NEC is capped at $64,800 ($360,000 × 18%), leaving at least some room for employee deferrals.

The squeeze income level by carrier

The squeeze begins when employer NEC exceeds $47,500 — the amount left after the $24,500 standard deferral is subtracted from the $72,000 §415(c) limit. Here is where that threshold falls by NEC rate:

Squeeze begins when NEC × eligible comp > ($72,000 − $24,500). Bucket full when NEC × eligible comp ≥ $72,000. Eligible comp capped at $360,000 under §401(a)(17).

Catch-up contributions: outside the §415(c) bucket

Unlike regular employee deferrals, catch-up contributions under §414(v) are explicitly excluded from the §415(c) annual additions limit. They are available in addition to the bucket — even if the bucket is completely full from employer NEC alone. This is one of the most underused strategies for senior mainline captains in their 50s and early 60s:

• Age 50–59, 64+: An additional $8,000 in 2026, on top of whatever regular deferrals you can make.¹
• Ages 60–63 only (SECURE 2.0 "super catch-up"): An additional $11,250 instead of $8,000.¹ This is a specific provision for these four ages — 64-year-olds revert to the standard $8,000.

When the bucket is full: your overflow options

Overflow mechanisms (Delta, United)

Delta and United operate MBCBP (money balance cash balance plan) and CBP/RHA (company benefit plan / retirement health account) overflow mechanisms respectively. When the employer NEC would otherwise exceed the §415(c) limit, the excess is redirected into a separate plan governed by §415(b) — an entirely different, larger limit. This preserves the full value of the employer contribution even when the §415(c) bucket is full. Confirm with HR each year whether the overflow is active for your plan year and how the elections work.

When there's no overflow

American Airlines, Southwest (for 2026), Alaska, JetBlue, Atlas, and most regional carriers have no approved overflow mechanism. The employer NEC is simply limited to the §415(c) cap — any NEC that would exceed $72,000 is not deposited anywhere. Compensation above the squeeze point generates no additional employer retirement contribution.

For pilots in this situation, the remaining tax-advantaged options are:

1. Backdoor Roth IRA. At mainline income above the $252,000 MFJ phase-out, you can't contribute directly. A non-deductible traditional IRA contribution followed by immediate Roth conversion still works — if you don't have other pre-tax IRA balances that would trigger the pro-rata rule. See the Roth conversion strategy guide.
2. Taxable brokerage. After tax-advantaged space is exhausted, a low-cost index fund brokerage account provides long-term capital gains treatment (0–20%) versus the ordinary income rates on traditional 401(k) withdrawals. Not as good as pre-tax deferral, but better than spending the surplus.
3. Solo 401(k) for self-employment income. Sim instructors, check airmen with consulting arrangements, or pilots with other self-employment income can open a solo 401(k) under a separate EIN. This creates an entirely separate §415(c) bucket — up to $72,000 in 2026 — independent of the airline plan.
4. Health Savings Account (HSA). If you're enrolled in a high-deductible health plan, the HSA ($4,400 self-only / $8,750 family for 2026) is triple tax-advantaged and invested for retirement. Invest rather than spend for maximum long-term benefit — but stop contributions 6 months before Medicare begins at mandatory retirement at 65. See the HSA strategy guide for pilots.
5. Deferred compensation (if offered). Delta introduced a nonqualified deferred compensation plan in 2026 for pilots 55+ (MOU 25-02). NQDC deferral is uncapped but is an unsecured creditor claim — carrier bankruptcy risk is real. See the pilot deferred compensation guide.

UPS and Hawaiian: dual-plan pilots have two buckets

Pilots at UPS and Hawaiian Airlines have both a defined-benefit pension and a defined-contribution 401(k). These are governed by different limits:

• §415(b) limits the annual benefit from a DB pension plan — currently $280,000/year for 2026. UPS's A Plan DB pension accrual and Hawaiian's frozen DB pension accrue against this separate limit.
• §415(c) governs only the DC plan — UPS's B Plan 12% NEC and 401(k) deferrals; Hawaiian's 15% NEC and 401(k) deferrals.

These limits are independent. A UPS captain benefiting from the A Plan pension does not lose any §415(c) room for 401(k) contributions. Use the calculator above with 12% for UPS to see only the DC-plan picture.