What Do W-2 Box 14 Codes U, V, W, X, Y, Z Mean?

Box 14 on your W-2 is a catch-all field, and the codes you see there are whatever shorthand your employer chose to use. Unlike Box 12, which uses IRS letter codes with fixed meanings, Box 14 has no standardized coding system. The IRS instructions tell employers they “may also use this box for any other information that you want to give to your employee” and simply require them to “label each item.”¹ So the same withholding might read “SDI” on one W-2 and “CASDI” on another. Most Box 14 entries are informational, but a handful affect what you owe or what you can deduct.

Why Box 14 Codes Aren’t Standardized

This is the point that trips people up. Box 12 codes (D for 401(k) deferrals, W for HSA contributions, AA for Roth 401(k), and so on) are assigned by the IRS and tax software knows exactly how to handle them. Box 14 labels are your employer’s own shorthand. If you’re searching for the meaning of a specific letter or abbreviation in Box 14, the answer depends on your employer’s payroll conventions and, often, on the state you work in. When a label is unclear, your final pay stub of the year is the fastest way to identify what the number represents, because the year-to-date columns should match.

Common Box 14 Entries and What They Mean

The IRS lists examples employers may put in Box 14: state disability insurance taxes, union dues, uniform payments, health insurance premiums deducted, nontaxable income, educational assistance payments, and clergy housing allowances.¹ In practice, what you’ll see depends on your state and your benefits:

SDI or CASDI is state disability insurance withholding, mandatory in certain states. Labels vary: “SDI,” “CASDI,” “NJ SDI,” and similar.
SUI is state unemployment insurance, where the state requires an employee contribution.
PFL, FLI, PFML, or FAMLI are paid family and medical leave contributions withheld under state programs.
UNION or DUES is the annual total of union dues deducted from your pay.
Health insurance premiums reported here are after-tax deductions. Pre-tax premiums paid through a Section 125 cafeteria plan are already excluded from Box 1 wages and usually don’t appear separately.
Educational assistance up to $5,250 per year is excluded from wages under Section 127. Your employer may note the amount for your records even though it doesn’t add to taxable income.¹
Uniform payments are amounts your employer paid or reimbursed for required uniforms.

Retirement Contributions That Belong in Box 14

Box 12 handles the main retirement codes, but the IRS specifically directs employers to report certain pension items in Box 14 instead:¹

Section 414(h)(2) required contributions. State and local government employees often must contribute to a public pension. These mandatory contributions are “picked up” by the employer under Section 414(h)(2) and belong in Box 14, never in Box 12. Labels include “414H,” “IRC414H,” and “RETCONT.”
Voluntary after-tax contributions. Non-Roth, after-tax retirement contributions. This is not the same as a Roth contribution (Box 12 code AA or BB). Reporting here is optional, so if your employer doesn’t include it, keep your own records.
Employer matching and nonelective contributions to your retirement account.
USERRA make-up contributions. If you returned from military service and your employer made retroactive pension contributions under the Uniformed Services Employment and Reemployment Rights Act, those amounts appear in Box 14, broken out by year.

Specialty Entries

Clergy Housing Allowance

If you’re an ordained minister, your employer may report your housing or parsonage allowance in Box 14. The allowance is excluded from gross income for income tax but is still subject to self-employment tax.² The excludable amount is the smallest of: the amount your church officially designated in advance, what you actually spent on housing, or the fair rental value of the home including furnishings and utilities. Any excess is taxable wages reported on line 1h of Form 1040.

Railroad Retirement Taxes

Railroad employers use Box 14 to report Tier 1 tax, Tier 2 tax, Medicare tax, Additional Medicare Tax, and total RRTA compensation, each with its own label. These take the place of the Social Security and Medicare figures shown in Boxes 4 and 6 for non-railroad workers. If you had more than one railroad employer during 2026 and more than $11,439 in Tier 1 tax was withheld, you can claim the excess on Form 1040; for Tier 2, the multi-employer over-withholding threshold is $6,717.90, and you claim it on Form 843.¹

Personal Use of a Company Vehicle

If your employer included 100% of a company vehicle’s annual lease value in your income, that amount must also appear in Box 14 or on a separate statement.¹ It tells you how much of your Box 1 wages came from the personal-use value of the vehicle rather than cash pay.

Which Box 14 Entries Actually Affect Your Federal Return

Most entries are informational. A few aren’t.

State and Local Taxes

State disability insurance, state income tax, and local wage tax withholdings shown in Box 14 can count toward the state and local tax (SALT) deduction on Schedule A if you itemize. For 2026, the SALT deduction is capped at $40,000 ($20,000 if married filing separately), with the cap reduced for filers whose modified adjusted gross income exceeds $505,000 ($252,500 for married filing separately). The cap cannot fall below $10,000 regardless of income.³ If you take the standard deduction, these amounts don’t change your federal return.

Union Dues

Union dues in Box 14 are not deductible on your federal return under current law. The Tax Cuts and Jobs Act suspended the deduction for unreimbursed employee business expenses, including union dues, for tax years 2018 through 2025, and the suspension has been extended through at least 2028. Some states still allow a deduction for union dues on the state return, which is why your employer reports the amount at all.

After-Tax Retirement Contributions

If Box 14 shows voluntary after-tax (non-Roth) contributions, that figure is your cost basis in the account. You won’t owe federal tax on that money again when you withdraw it. Because this reporting is optional, its absence doesn’t mean you made no after-tax contributions. Verify against your plan statements and keep your own records.

Entering Box 14 in Tax Software

Tax software will ask you to type in the label as it appears on your W-2, enter the dollar amount, and pick a category from a dropdown. Common categories include state disability insurance, paid family leave, union dues, and various state-specific withholdings. If nothing matches, choose “Other (not classified)” and the software will decide whether the amount affects your return. Miscategorizing is where mistakes happen. Labeling an SDI contribution as local income tax, for example, can misroute the amount on Schedule A.

What to Do If a Box 14 Entry Is Wrong

Because the labels aren’t standardized, errors turn up here more often than elsewhere on the W-2. A wrong SDI figure can throw off your SALT deduction. A wrong after-tax retirement contribution figure can cause a headache decades later when you take distributions and need to prove basis.

Start with your payroll department and ask for a corrected Form W-2c. Most errors are resolved at this step. If your employer hasn’t issued a correction by the end of February, you can call the IRS at 800-829-1040 or visit a Taxpayer Assistance Center; the IRS will contact your employer requesting a corrected W-2 within ten days.⁴ Before you file, compare every Box 14 entry against your final pay stub of the year. The year-to-date totals should match line for line.

1
Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026)
2
Internal Revenue Service. Ministers’ Compensation and Housing Allowance
3
Internal Revenue Service. Topic No. 503, Deductible Taxes
4
Internal Revenue Service. W-2 – Additional, Incorrect, Lost, Non-Receipt, Omitted