topic W-2 Box 12 in Get your taxes done using TurboTax

W-2 Box 12

sterburns — Mon, 09 Mar 2026 11:45:22 GMT

Box 12 has the code D then number 21 and the amount. What does the number 21 stand for?

Re: W-2 Box 12

JohnB5677 — Wed, 06 Apr 2022 14:33:05 GMT

D21 indicates your make-up contributions for 2021 under the Uniformed Services Employment and Reemployment Rights Act (USERRA).

For example, elective deferrals of $2,250 for 2020 and $1,250 for 2021 under USERRA under a section 401(k) plan are reported in box 12 as follows.

D 20 2250.00, D 21 1250.00.

Re: W-2 Box 12

SteamTrain — Wed, 06 Apr 2022 17:06:52 GMT

[Edited]

OK...detailed fully proper response from @dmertz below:

He understands all the gory-specific-details that the rest of us do not

Re: W-2 Box 12

dmertz — Wed, 06 Apr 2022 16:37:42 GMT

"Occasionally, an employer has to make a late makeup 401k contribution for a prior year, so an entry labelled D20, on a 2021 W-2 form, would indicate that such a makeup contribution was made for the year before (i.e. 2020). "

That not how this works. Code D reports employee elective deferrals. If the employer failed to include the correct code-D amount on the 2020 W-2, the employer must correct the 2020 W-2.

The D21 indicates a USERRA make-up contribution. Since it was made in the same year as the year of the W-2, the "21" is redundant and can be omitted. If there is a separate code-D amount with no year designation, the two amounts can be combined. (If the USERRA amount was instead for a prior year, the USERRA amount should be omitted.)

https://www.irs.gov/retirement-plans/retirement-plans-faqs-regarding-userra-and-sscra