Key Takeaways for 2026 Compliance
- Form W-2 reports annual gross wages, federal/state tax withholdings, and FICA taxes.
- Employers must mail Form W-2 to employees by January 31.
- Box 1 shows taxable federal income after pre-tax retirement deductions.
- Box 3 Social Security wages are capped at $184,500 for 2026 ($176,100 for 2025).
- Box 5 Medicare wages are uncapped (+0.9% additional tax on wages over $200,000).
- Generate accurate employee paystubs matching year-end W-2 totals free online.
Official IRS Form W-2 Guide: Wage & Tax Statement
Learn how to read Boxes 1 through 20 on your Form W-2, verify year-end paystub totals, or create professional paystubs online in 60 seconds.
What Is IRS Form W-2 & Who Receives It?
Form W-2 (Wage and Tax Statement) is the mandatory annual tax form that employers file with the Social Security Administration (SSA) and issue to every W-2 employee by January 31 following the tax year.
Form W-2 Boxes 1 to 20 Comprehensive Field Reference
Key box definitions on IRS Form W-2:
| Box # | Field Name | Tax Impact & 2026 Rules |
|---|---|---|
| Box 1 | Wages, tips, other compensation | Federal taxable wages (Gross Pay minus pre-tax 401k/HSA/Health Insurance). |
| Box 2 | Federal income tax withheld | Total Federal Income Tax (FIT) deducted from paychecks during the year. |
| Box 3 | Social Security wages | Wages subject to 6.2% SS tax (Capped at $184,500 for 2026 / $176,100 for 2025). |
| Box 4 | Social Security tax withheld | 6.2% of Box 3 (Maximum $11,439.00 for tax year 2026). |
| Box 5 | Medicare wages and tips | Total Medicare wages (No wage base limit; includes 401k contributions). |
| Box 6 | Medicare tax withheld | 1.45% of Box 5 (+ 0.9% Additional Medicare tax for wages > $200k). |
| Box 12 | Deferred compensation codes | Report 401(k) contributions (Code D), HSA (Code W), Employer Health Care (Code DD). |
| Boxes 15-20 | State & Local tax withholding | State Employer ID, State Taxable Wages, SIT withheld, and Local income taxes. |
Box 1 vs Box 3 vs Box 5 Salary Calculation Math
Why is Box 1 often smaller than Box 3 and Box 5 on your Form W-2? Pre-tax benefit deductions lower federal income tax but remain subject to FICA taxes:
Real-World $60,000 W-2 Salary Math Breakdown:
- Gross Annual Salary: $60,000
- Pre-Tax 401(k) Contribution: -$5,000
- Pre-Tax Health Insurance Premiums: -$2,000
- Box 1 (Federal Taxable Wages): $53,000 ($60,000 - $5,000 - $2,000)
- Box 3 & Box 5 (FICA Wages): $58,000 ($60,000 - $2,000 health insurance only; 401k is FICA taxable)
Common Box 12 Benefit Codes (401k, HSA, Health Care)
Form W-2 Employer Filing Deadlines (January 31)
Federal law mandates that employers must mail or electronically deliver Copy B of Form W-2 to employees by January 31. Simultaneously, Copy A must be submitted to the Social Security Administration (SSA) along with Form W-3 transmittal.
Related IRS Tax & Payroll Guides
Paystub vs W-2 Guide →
Learn how monthly paystubs reconcile with annual Form W-2.
Paystub Tax Deductions Guide →
Understand FIT, FICA, OASDI, and pre-tax paystub codes.
How to Create Paystub Online →
Generate print-ready 2026 PDF paystubs free.
Frequently Asked Questions
What is IRS Form W-2 used for?
Form W-2 (Wage and Tax Statement) is an annual federal tax document issued by employers to W-2 employees and the Social Security Administration (SSA) by January 31 (February 1, 2027 for tax year 2026 as Jan 31 is a Sunday), reporting annual gross wages and itemized tax withholdings.
Why is Box 1 on Form W-2 different from Box 3 and Box 5?
Box 1 shows federal taxable wages (after subtracting employer-sponsored pre-tax deductions such as 401(k), 403(b), HSA, and Section 125 health insurance). Box 3 (Social Security) and Box 5 (Medicare) include 401(k) contributions because elective salary deferrals remain subject to FICA payroll taxes.
What is the Social Security wage base limit for 2026?
For tax year 2026, the Social Security wage base limit is $184,500 (up from $176,100 in 2025). Wages above $184,500 are exempt from the 6.2% Social Security tax.
What is the deadline for employers to mail Form W-2?
Employers must furnish Copy B of Form W-2 to employees and file Copy A with the SSA by January 31 following the close of the tax year (or the next business day, February 1, 2027 for 2026 tax returns).
- IRS.gov: Form W-9 (Rev. March 2024) – Request for Taxpayer Identification Number and Certification (OMB No. 1545-0029).Official Source ↗
- Internal Revenue Code: 26 U.S. Code § 3406 — Mandatory 24% Backup Withholding on Reportable Payments (26 U.S.C. § 3406).Official Source ↗
- Treasury Regulations: 26 CFR § 31.3406(h)-3 — Certificates of Taxpayer Identification Number and Signature Verification (Treas. Reg. § 31.3406(h)-3).Official Source ↗
- IRS Publication 1281: Backup Withholding for Missing and Incorrect Name/TIN(s) (Payers Guide) (IRS Pub. 1281 (Rev. 2026)).Official Source ↗