Form W2 is generally issued by employer to employees. There are several items that go to Box 12 of from W2. And if the code is not listed under code A through Code HH, go to box 14 and put the item there instead of box 12. For example, section 414(h)(2) contribution goes to box 14.
W2 Box 12 Codes:
A— Uncollected social security or RRTA tax on tips.
B — Uncollected Medicare tax on tips.
C—Taxable cost of group-term life insurance over $50,000.
D—Elective deferrals under a section 401(k) cash or deferred arrangement (plan).
E—Elective deferrals under a section 403(b) salary reduction agreement.
F—Elective deferrals under a section 408(k) (6) salary reduction SEP. General Instructions for Forms W-2 and W-3 (2022)-19
G—Elective deferrals and employer contributions (including nonelective deferrals) to any governmental or nongovernmental section 457(b) deferred compensation plan.
H—Elective deferrals under section 501(c) (18)(D) tax-exempt organization plan.
J—Nontaxable sick pay.
K—20% excise tax on excess golden parachute payments (not applicable to Forms W-2AS, W-2CM, W-2GU, or W-2VI).
L—Substantiated employee business expense reimbursements.
M—Uncollected social security or RRTA tax on taxable cost of group-term life insurance over $50,000 (for former employees).
N—Uncollected Medicare tax on taxable cost of group-term life insurance over $50,000 (for former employees).
P—Excludable moving expense reimbursements paid directly to a member of the U.S. Armed Forces.
Q—Nontaxable combat pay.
R—Employer contributions to an Archer MSA.
S—Employee salary reduction contributions under a section 408(p) SIMPLE plan. Show deferrals under a section 408(p) salary reduction SIMPLE retirement account. (You may be able to claim the Saver’s Credit on this)
V—Income from the exercise of non-statutory stock option(s).
W—Employer contributions to a health savings account (HSA).
Y—Deferrals under a section 409A nonqualified deferred compensation plan.
Z—Income under a nonqualified deferred compensation plan that fails to satisfy section 409A.
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.
EE—Designated Roth contributions under a governmental section 457(b) plan.
FF—Permitted benefits under a qualified small employer health reimbursement arrangement.
GG—Income from qualified equity grants under section 83(i).
HH—Aggregate deferrals under section 83(i) elections as of the close of the calendar year.