Deferred Compensation on W-2: Box 11, Box 12, and Code Z 409A

Deferred compensation on a W-2 shows up in two main places: Box 12 for qualified retirement plan deferrals like a 401(k), 403(b), governmental 457(b), or SIMPLE IRA, and Box 11 for non-qualified deferred compensation (NQDC). A letter code next to the Box 12 figure tells the IRS which type of plan it came from. If a non-qualified plan runs afoul of Section 409A, the deferred balance also lands in Box 1 as wages and in Box 12 under Code Z. FICA wages in Boxes 3 and 5 sometimes include NQDC amounts that Box 1 does not, because Social Security and Medicare tax those dollars on a different schedule than income tax.

Box 12: Qualified Plan Deferrals

When you elect to contribute part of your paycheck to a qualified retirement plan, the amount lands in Box 12 with a letter code identifying the plan. Pre-tax contributions also reduce the taxable wages reported in Box 1, which is why Box 1 is usually smaller than your gross pay. Box 12 itself is informational; the IRS uses it to check that you stayed within the annual contribution limit.¹

The codes you’ll most often see for deferred compensation:

Code D — elective deferrals to a 401(k) plan.
Code E — elective deferrals to a 403(b) plan.
Code G — deferrals and employer contributions to a governmental or nongovernmental 457(b) plan.
Code S — salary reduction contributions to a SIMPLE IRA.
Code W — employer and cafeteria-plan contributions to a Health Savings Account.

Employer matching contributions and profit-sharing amounts don’t appear in Box 12. Only deferrals that came out of your own paycheck show up there.¹

Roth Contributions Look Different

Designated Roth contributions use their own codes: AA for Roth 401(k), BB for Roth 403(b), and EE for Roth governmental 457(b). Because Roth deferrals are made with after-tax dollars, the amount is included in Box 1, Box 3, and Box 5 in addition to Box 12.¹ There’s no wage reduction, because you’re paying the tax now.

A 2026 wrinkle worth checking on your own W-2: if your Box 3 (Social Security wages) from the same employer exceeded $150,000 in the prior year, catch-up contributions must be designated Roth. That shifts your catch-up amount from Code D, E, or G to Code AA, BB, or EE and brings it into Box 1.

2026 Contribution Limits

For 2026, the elective deferral limit for 401(k), 403(b), and governmental 457(b) plans is $24,500.² Participants 50 or older can add $8,000 in catch-up contributions for a total of $32,500. Under the SECURE 2.0 enhanced catch-up, participants aged 60 through 63 can add $11,250 instead, for a total of $35,750. SIMPLE IRA salary reductions are capped at $17,000, with some employers offering $18,100. HSA contributions are capped at $4,400 (self-only) or $8,750 (family).³

Box 11: Non-Qualified Deferred Compensation

Box 11 is labeled “Nonqualified plans,” and its job is narrower than it looks. It doesn’t drive your income tax bill on its own. It exists so the Social Security Administration can tell whether wages reported in Box 1, Box 3, or Box 5 were actually earned in a prior year. Without that signal, the SSA might credit earnings to the wrong year when it later calculates your benefits.⁴

If your NQDC plan complies with Section 409A, the deferred amount stays out of Box 1 during the years you’re deferring. You won’t see any income tax hit on your W-2 until the money is actually distributed. When distribution happens, the payout appears as Box 1 wages, and Box 11 flags the portion attributable to work performed in earlier years.

Why FICA Wages Can Include NQDC Before Box 1 Does

NQDC is subject to Social Security and Medicare tax long before it’s subject to income tax. Under the special timing rule, NQDC becomes subject to FICA at the later of when you performed the services or when the substantial risk of forfeiture lapses.⁵

The practical effect: your W-2 might include an NQDC amount in Box 3 (Social Security wages) and Box 5 (Medicare wages) while leaving it out of Box 1. The 2026 Social Security wage base is $184,500, so NQDC only pushes Box 3 up if your other wages haven’t already hit that ceiling.⁶ Medicare has no cap, so Box 5 always reflects the NQDC amount. Your employer tracks the early FICA taxation so the same dollars aren’t hit again when the payout comes.

Even without a 409A violation, NQDC can become currently taxable when a substantial risk of forfeiture lapses. If your right to the money originally depended on continued employment or hitting a performance goal, the deferred amount is included in Box 1 the year that condition is satisfied, whether or not you’ve received the cash.

Box 12 Code Z: When Section 409A Is Violated

Section 409A sets the rules for non-qualified deferred compensation. Three of them drive most W-2 problems:

Deferral elections must be made before the start of the year in which you’ll earn the compensation. For performance-based compensation tied to a service period of at least 12 months, the deadline is six months before the end of that period.⁷
Distributions can only happen upon separation from service, disability, death, a fixed date or schedule in the plan, a change in corporate ownership, or an unforeseeable emergency.
You and your employer cannot accelerate the timing of a payout beyond what the plan originally specified.

When a plan fails any of these rules, the entire deferred balance becomes immediately taxable, not just the current year’s contribution. The forced inclusion shows up as additional wages in Box 1 and in Box 12 under Code Z.⁸ On top of the regular income tax, you owe a flat 20% penalty on the non-compliant amount plus interest running back to the year the compensation was originally deferred.⁷

A large balance that triggers Code Z can generate a tax bill that exceeds the cash you have on hand. You may owe income tax, the 20% penalty, and interest all at once on money you haven’t received.

When Deferred Compensation Is Paid Out

Qualified plan distributions from a 401(k), 403(b), or governmental 457(b) are reported on Form 1099-R, not a W-2, because you’re usually no longer an active employee earning wages.⁹ Withdrawals before age 59½ generally trigger a 10% early distribution penalty on top of ordinary income tax, subject to several exceptions.¹⁰

NQDC payouts work differently. They’re reported on the W-2, not on Form 1099-R, and appear as Box 1 wages in the year you receive them.⁹ Because the money was never taxed for income tax purposes while it was deferred, the full amount is taxed at your marginal rate on the way out. Box 11 tells the SSA which portion of those Box 1 wages was already subject to FICA in a prior year, so those dollars aren’t hit with Social Security and Medicare tax a second time.

NQDC distributions aren’t subject to the 10% early withdrawal penalty regardless of your age. They are treated as supplemental wages for withholding: 22% federal in 2026, or 37% on amounts above $1 million paid to the same employee during the calendar year.¹¹ If a lump sum pushes you into a higher bracket, the flat 22% withholding may not cover what you owe, and estimated tax payments can close the gap.

Independent Contractors Don’t See This on a W-2

NQDC paid to an independent contractor doesn’t touch a W-2 at all. Compliant deferrals of $600 or more are reported in Box 12 of Form 1099-MISC, and non-compliant amounts go in Box 15 of the same form.¹²

Fixing W-2 Errors and Excess Deferrals

Errors involving deferred compensation are common, especially with NQDC where FICA timing and income tax timing pull apart. If the Box 12 code is wrong, Box 11 is missing an amount, or Boxes 3 and 5 don’t reflect the special timing rule, your employer files a corrected Form W-2c with the Social Security Administration and gives you a copy.¹³

Excess deferrals work differently. If you changed jobs mid-year and your combined 401(k) contributions across both employers exceeded $24,500, the excess must be withdrawn by April 15 of the following year. No W-2c gets issued for the excess. Instead, the corrective distribution and any allocable earnings are reported on a Form 1099-R in the year the excess is returned, and you still have to report the full excess on your tax return for the year the contributions were made. Your second employer has no way of knowing what you contributed at the first, so the tracking is on you.

1
Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3
2
Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026
3
Internal Revenue Service. Expanded Availability of Health Savings Accounts
4
Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3 – Section: Box 11
5
eCFR. 26 CFR 31.3121(v)(2)-1
6
Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet
7
Office of the Law Revision Counsel. 26 USC 409A
8
Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3 – Section: Box 12 Code Z
9
Internal Revenue Service. Instructions for Forms 1099-R and 5498
10
Internal Revenue Service. Retirement Topics – Exceptions to Tax on Early Distributions
11
Internal Revenue Service. 2026 Publication 15 – Section: Supplemental Wages
12
Internal Revenue Service. Instructions for Forms 1099-MISC and 1099-NEC
13
Internal Revenue Service. About Form W-2c, Corrected Wage and Tax Statements