Form W-2

Form W-2Wage and Tax Statement

12b — Box 12b Codes Updated for tax year 2025

What this line means

A continuation of Box 12a. If your employer needs to report more than one coded benefit, the second entry goes here. The format is the same: a letter code followed by a dollar amount. Box 12b uses the same set of codes as Box 12a — the box number does not change the meaning of the code.

Does this apply to you?

  • You have more than one type of coded compensation or benefit reported by your employer
  • You contributed to a retirement plan and also received employer-paid health coverage (two separate codes)
  • You have both a traditional 401(k) and a Roth 401(k) — each gets its own code and line in Box 12

Easy to overlook

The order of codes across 12a-12d does not matter Employers can list codes in any order across the four Box 12 slots. Code D (401(k)) might appear in 12a for one employer and 12c for another. The code itself determines what the amount represents, not which sub-box it appears in. When comparing W-2s from different employers, focus on the letter codes, not the box positions. 1 IRS W-2 Instructions — Box 12 code definitions

Code C amounts are already in Box 1 If Box 12b (or any Box 12 slot) shows Code C — the taxable cost of group-term life insurance over $50,000 — that amount is already included in your Box 1 wages. This catches filers off guard because they did not receive the money as cash, but the IRS treats the imputed value of excess life insurance as taxable compensation. 2 IRS Publication 525 — Taxable and Nontaxable Income

Watch out for this

Manually adding Box 12b amounts to your income on your tax return. Tax software reads the codes and handles them correctly. Filers who manually enter W-2 data sometimes enter Box 12 amounts as “other income” in addition to Box 1, creating a duplicate. Each Box 12 code has specific tax treatment — some reduce income, some are informational, and most are already reflected in Box 1.

Footnotes

  1. IRS Instructions for Forms W-2 and W-3, Box 12 Codes. https://www.irs.gov/instructions/iw2w3 ↩

  2. IRS Publication 525, Taxable and Nontaxable Income. https://www.irs.gov/pub/irs-pdf/p525.pdf ↩

Related lines on your return

These lines on your tax return connect to this one — click any to learn more.

  • Box 12aFirst coded benefit entry; same format and code set as Box 12b
  • Box 12c, 12dThird and fourth coded benefit entries if needed
  • Box 1The net result after all pre-tax deductions and taxable additions from Box 12 codes
Back to top