No, don't check the box. Request a corrected W-2 from your employer. If you have a 401k through your employer but the box is not checked, this may have certain tax implications.
For example:
The BUT is....did you actually contribute to the 401k at any time during 2021?
Your contributions would be shown in box 12 with a code "D" next to the $$ amount.
(or code "AA" if contributions were made to a ROTH 401k)
I thought of that too. I did contribute to it and there is an amt in box 12. So my assumption is that I should have a W-2 with box 13 checked if that's the case?
It's not necessarily the case that the box should be checked. If you began employment (or otherwise began participation in the 401(k) plan) with this employer in 2021 and the 401(k) plan uses a fiscal year instead of a calendar year, it's possible that your participation during 2021 makes you covered for 2022 but not 2021. You'll need to ask the employer the end date of the plan's year and if box 13 Retirement plan is correct or not. You are covered for the calendar year in which the plan year for which additions were made ends.
My employer sent out a corrected w2 the day after I filed b/c they failed to check box 13 retirement plan, even though they put the correct $ amount in box 12b code D. My return has been in pending status for 24 hours. My employer claims I do not need to amend my return. Is this true even if I made non-deductible contributions to an IRA and converted the entire account to a Roth IRA in the same year? Thanks.