How to Fill Out a W-2 for a Single Person: Boxes, Filing, and Fixes

Filling out a W-2 for a single person follows the same box-by-box structure as any other W-2, with a few spots where filing status actually changes the numbers: the federal withholding in Box 2 reflects the single rate the employee chose on their Form W-4, the Additional Medicare Tax threshold in Box 6 kicks in at $200,000 of that one person’s wages, and the retirement plan checkbox in Box 13 can limit their traditional IRA deduction at tax time. Everything else is mechanical, driven by payroll records and the employee’s Social Security card.¹

What You Need Before You Start

Pull three things: the employee’s most recent Form W-4, a copy of or reference to their Social Security card, and your year-end payroll summary. The W-4 tells you the filing status and any additional withholding they elected. The Social Security card is the source of truth for the name and number that go on the form. And the payroll summary supplies every dollar figure on the return.

Verify the name and Social Security number before you type anything. A name mismatch is one of the most common reasons the Social Security Administration rejects a W-2 filing.²

Boxes A Through F: Who the Form Is About

The lettered boxes identify the employer and the employee.

Box a: the employee’s nine-digit Social Security number, exactly as it appears on their card. Do not substitute an Individual Taxpayer Identification Number.
Box b: your Employer Identification Number, formatted XX-XXXXXXX.
Box c: your legal business name and address, matching what appears on Form 941 or 944.
Box d: an optional control number for your own tracking. Leave it blank if you do not use one.
Box e: the employee’s full legal name, first, middle initial, last, matching the Social Security card.
Box f: the employee’s current mailing address.

Boxes 1 Through 6: Wages and Federal Withholding

These six boxes are the financial core of the return.

Box 1: Taxable Wages, Tips, and Other Compensation

Report total taxable pay for the year: regular wages, bonuses, commissions, reported tips, taxable fringe benefits. Subtract elective 401(k) deferrals, HSA contributions made through a cafeteria plan, and pretax health insurance premiums, because those come out before federal income tax. Roth 401(k) contributions stay in Box 1 because they were already taxed.³

Box 2: Federal Income Tax Withheld

Enter the total federal income tax you withheld across the year. For a single person, this figure reflects the choice they made on Step 1(c) of Form W-4. An employee who checked “Single or Married Filing Separately” is withheld at higher rates than one who checked “Married Filing Jointly” at the same wage level, because the single brackets are narrower. The Box 2 total must match what you reported on your quarterly payroll tax filings.

Boxes 3 and 4: Social Security Wages and Tax

Box 3 is wages subject to Social Security tax. Pretax 401(k) deferrals stay in Box 3 even though they came out of Box 1. The box is capped at the annual wage base, $184,500 for 2026.⁴ If the employee earned more, enter $184,500 and stop.

Box 4 is 6.2% of Box 3. At the wage base, the maximum for 2026 is $11,439.⁴

Boxes 5 and 6: Medicare Wages and Tax

Box 5 is Medicare wages, uncapped. Box 6 is 1.45% of Box 5.⁴

Here is where a single filer needs particular attention. Once wages cross $200,000 in the calendar year, you must withhold an extra 0.9% Additional Medicare Tax on every dollar above that line. That $200,000 threshold applies to the individual employee’s wages from you, without regard to their filing status or their spouse’s income, so a single person hits it on their own earnings. Combine the extra 0.9% with the regular 1.45% and report the total in Box 6. Do not break it out into a separate box.⁵ Some employers list the Additional Medicare Tax amount in Box 14 as a courtesy to the employee.⁶

Boxes 7 Through 14: Tips, Benefits, and Coded Amounts

Boxes 7 and 8: Tips

Box 7 reports Social Security tips the employee reported to you. Box 8 is allocated tips, which applies only to certain food and beverage establishments where you allocate a share of total tips to employees who reported less than expected. Allocated tips do not appear in Boxes 1, 3, 5, or 7.

Boxes 10 and 11: Dependent Care and Deferred Compensation

Box 10 is the total dependent care benefit the employee received or set aside through a dependent care FSA. For 2026, a single filer can exclude up to $7,500; anything above that is taxable and rolls into Box 1.⁷

Box 11 reports distributions from a nonqualified deferred compensation plan during the year.

Box 12: Coded Entries

Box 12 has four sub-slots (12a through 12d), each with room for one letter code and a dollar amount. The codes you will use most often:

Code C: taxable cost of group-term life insurance coverage above $50,000.
Code D: elective deferrals to a 401(k) plan.
Code DD: total cost of employer-sponsored health coverage, employer and employee share combined. Informational only; not taxable.⁸
Code E: elective deferrals to a 403(b) plan.
Code G: elective deferrals and employer contributions to a 457(b) plan.
Code W: employer and cafeteria-plan employee contributions to a health savings account.

Box 13: Checkboxes

Three checkboxes sit here. Statutory employee applies to a narrow group such as full-time life insurance salespeople and certain home workers who owe Social Security and Medicare but not federal income tax withholding. The Retirement plan box is checked if the employee actively participated in an employer-sponsored plan during the year; for a 401(k), that means either the employee or you actually contributed, not just that they were eligible.² For a single filer, this check matters at tax time: an active participant may lose part or all of the traditional IRA deduction depending on income.

Box 14: Other

Box 14 is a free-form area for items that lack a dedicated box: state disability insurance withheld, union dues, educational assistance, uniform payments, and the like.

Boxes 15 Through 20: State and Local Taxes

The bottom of the form handles state and local reporting. Two rows are printed, so you can list up to two states or localities on one W-2.

Box 15: two-letter state abbreviation and your state tax ID number.
Box 16: wages subject to state income tax. This may differ from Box 1 because states add back or exclude items differently than the federal government.
Box 17: state income tax you withheld.
Boxes 18 through 20: local wages, local tax withheld, and locality name, if a city or county levies its own income tax.

If the state has no income tax, leave 15 through 17 blank. Leave 18 through 20 blank where no local tax applies.²

Copies, Deadlines, and How to File

Each W-2 you complete generates several copies. Copy A goes to the Social Security Administration on the official red-ink scannable form or electronically. Copy B goes to the employee for their federal return. Copy C is for the employee’s personal records. Copy 2 is for the employee’s state or local return. Copy D stays with you.

All copies, both the SSA filing and the employee’s, are due by January 31 of the year following the tax year. If an employee left mid-year and requests the W-2 in writing before then, you must furnish it within 30 days of the request whenever that 30-day window closes before January 31.¹

If you are filing 10 or more information returns of any kind combined in a calendar year, you must file electronically. Seven W-2s plus four 1099s puts you over the line for all 11.⁹ The SSA accepts electronic filings through Business Services Online. You can upload EFW2-formatted files from payroll software or use the free W-2 Online tool for up to 50 forms.¹⁰ Below the 10-return threshold, paper filing of Copy A is still allowed.

Missing January 31 or filing incorrect W-2s triggers per-form penalties that grow the longer the problem sits uncorrected, with a separate escalating scale for intentional disregard.¹¹

Fixing a Mistake After You File

If you discover an error after filing, correct it on Form W-2c, accompanied by Form W-3c as the transmittal. A separate W-3c is required for each tax year being corrected, and one is required even if the only fix is a name or Social Security number. File the correction as soon as you find the mistake and send the employee a corrected copy right away. The same 10-return electronic filing rule applies to W-2c forms. When correcting a dollar amount to zero, enter “-0-” rather than leaving the box blank.¹²

1
Office of the Law Revision Counsel. 26 U.S. Code 6051 – Receipts for Employees
2
Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3
3
Internal Revenue Service. General Instructions for Forms W-2 and W-3 (2026)
4
Social Security Administration. Contribution and Benefit Base
5
Internal Revenue Service. Topic No. 751, Social Security and Medicare Withholding Rates
6
Internal Revenue Service. Instructions for Form 8959 (2025)
7
Office of the Law Revision Counsel. 26 U.S. Code 129 – Dependent Care Assistance Programs
8
Internal Revenue Service. Form W-2 Reporting of Employer-Sponsored Health Coverage
9
Internal Revenue Service. E-file Information Returns
10
Social Security Administration. What You Can Do Online
11
Internal Revenue Service. Information Return Penalties
12
Social Security Administration. Helpful Hints to Forms W-2c/W-3c Filing