W-2 Box 12 Codes, A through TT

D is the one most employees have: elective deferrals to a 401(k). E is the 403(b) equivalent for schools and nonprofits, G the governmental 457(b), S a SIMPLE IRA. The pre-tax versions (D, E, G, S) reduce box 1 but not boxes 3 and 5, which is the usual reason box 1 is smaller than box 3. The Roth versions (AA, BB, EE) are after-tax and reduce nothing; they are reported so the IRS can police the annual limit. Any of these also ticks the retirement-plan box in box 13.

The taxable cost of employer-paid group-term life coverage above $50,000, from the IRS Table I rates. It is included in boxes 1, 3 and 5 already; code C tells the employee where that odd extra bit of income came from.

Employer contributions to a health savings account plus anything the employee contributed through a cafeteria plan, combined. Payroll-deducted HSA contributions are excluded from boxes 1, 3 and 5. The employee needs the figure for Form 8889, and it must not include contributions they made on their own outside payroll.

Informational only: the total premium for the employee's medical coverage, employer and employee shares together. It is not taxable and does not go on the return. Employers that filed fewer than 250 W-2s the prior year remain exempt under the IRS's transition relief, so a small employer may leave it off.

The One Big Beautiful Bill Act created deductions for qualified tips and qualified overtime, and the W-2 is how the employee proves the amounts. TP is the total cash tips the employee reported to you during the year (the deduction is capped at $25,000); when you report TP you must also complete box 14b with the Treasury tipped occupation code, 000 if the job is not on Treasury's list. TT is total qualified overtime compensation, meaning the premium half of FLSA time-and-a-half, not the whole overtime paycheck (deduction capped at $12,500, or $25,000 married filing jointly).

TA reports employer contributions under a section 128 Trump account contribution program, which starts July 4, 2026 and is limited to $2,500 per employee per year. None of the three exist on a 2025 W-2; the generator refuses them for that year.

Social Security and Medicare tax that should have been withheld but could not be, because a tipped employee's wages were too small to cover the tax on reported tips (A and B) or because a former employee's group-term life coverage continued after their last paycheck (M and N). The employee pays these on Schedule 2 of their return, on the uncollected-tax line.

V is the spread on nonstatutory stock options exercised in the year, already in boxes 1, 3 and 5. Y and Z are section 409A nonqualified deferred compensation, deferrals and includible income respectively. GG and HH cover section 83(i) qualified equity grants at private companies. Small employers without an equity plan never use any of these.