What is 12A on the W-2? I thought it was my 401K contribution but Turbo tax has it as taxes from c. instructions, UT on the 1040.

[JulieH1 · Accepted solution]

Please see the FAQs below for more information about W-2 Box 12 codes.

What do all the letter codes in Box 12 of my W-2 mean?  

The upper-case (capital) letters in Box 12 stand for various things:

• A: Uncollected social security or RRTA tax on tips reported to your employer
• B: Uncollected Medicare tax on tips reported to your employer (but not Additional Medicare Tax)
• C: Taxable cost of group-term life insurance over $50,000
• D: Contributions to your 401(k) plan
• E: Contributions to your 403(b) plan
• F: Contributions to your 408(k)(6) plan
• G: Contributions to your 457(b) plan
• H: Contributions to your 501(c)(18)(D) plan
• J: Non-taxable sick pay
• K: 20% excise tax on excess golden parachute payments
• L: Substantiated employee business expense reimbursements
• M: Uncollected social security or RRTA tax on taxable cost of group-term life insurance over $50,000 (only applies to former employees)
• N: Uncollected Medicare tax on taxable cost of group-term life insurance over $50,000 (but not Additional Medicare Tax) (only applies to former employees)
• P: Excludable moving expense reimbursements paid directly to employee
• Q: Nontaxable combat pay
• R: Employer contributions to an Archer MSA
• S: Contributions to your 408(p) SIMPLE plan
• T: Employer-provided adoption benefits
• V: Income from the exercise of non-statutory stock options
• W: Employer contributions (including employee contributions through a cafeteria plan) to an employee's health savings account (HSA)
• Y: Deferrals under section 409A on an nonqualified deferred compensation plan
• Z: Income under a nonqualified deferred compensation plan that fails to satisfy section 409A. This amount is subject to an additional 20% tax plus interest. TurboTax does not support the calculations for Code Z.
• AA: Designated Roth contributions under a section 401(k) plan
• BB: Designated Roth contributions under a section 403(b) plan
• DD: Cost of employer-sponsored health coverage. More info
• EE: Designated Roth contributions under a governmental section 457(b) plan
• FF: Permitted benefits under a qualified small employer health reimbursement arrangement

In addition, the four Box 12 lines are labeled 12a, 12b, 12c, and 12d, which are just line labels and have no meaning. Also, you can ignore See instructions for box 12 or See instrs for box 12 unless you're doing your taxes by hand.