Tax Guides

How to Read Your W-2 Form: A Beginner's Line-by-Line Guide

Every January, your employer mails or uploads a Form W-2 — the official record of everything you earned and everything withheld on your behalf. It's the single most important document you need to file your federal tax return. Here's exactly what every box means, why the numbers look the way they do, and how each piece maps to your 1040.

Updated March 2026 · 15 min read

What Is a W-2 and Who Gets One?

Form W-2 (Wage and Tax Statement) is issued by your employer to report your annual wages and the taxes withheld. Employers must send W-2s to employees by January 31 of the following year. The IRS also receives a copy — so the numbers are already in the system when you file.

You receive a W-2 if you were an employee (not an independent contractor). If you did freelance or gig work, that income is reported on Form 1099-NEC instead.

Key rule: Your employer sends the W-2 to you AND to the Social Security Administration (SSA), which shares it with the IRS. The IRS already knows what your W-2 says before you file — it uses this to cross-check your return.

Sample W-2 — Fictional Data

The examples below reference this fictional employee to make the numbers concrete. Jordan earns a $68,000 salary, contributes $7,500 to a traditional 401(k), pays $2,400/year in employer health insurance premiums (pre-tax), and contributes $1,200 to a Healthcare FSA. Jordan works in Texas (no state income tax).

Form W-2 — Wage and Tax Statement (Tax Year 2025)

Employee: Jordan M. Lee  |  SSN: ***-**-4521

Employer: Maple Street Solutions LLC  |  EIN: 45-1234567

Address: 820 Commerce Blvd, Austin, TX 78701

Box 1

Wages, tips, other comp.

Gross $68,000 minus 401(k) $7,500, health ins. $2,400, FSA $1,200

$56,900.00
Box 2

Federal income tax withheld

Withheld by employer based on W-4 elections

$5,800.00
Box 3

Social Security wages

$68,000 minus health ins. $2,400 and FSA $1,200 only — 401(k) doesn't reduce SS wages

$64,400.00
Box 4

Social Security tax withheld

6.2% × $64,400

$3,993.00
Box 5

Medicare wages and tips

Same as Box 3 (no cap on Medicare wages)

$64,400.00
Box 6

Medicare tax withheld

1.45% × $64,400

$933.80
Box 12a

Code D — 401(k) contribution

Traditional 401(k) — already excluded from Box 1, informational

$7,500.00
Box 12b

Code DD — Employer health coverage

Total cost of employer plan (employer + employee share) — NOT taxable, informational only

$12,000.00
Box 13

Retirement plan checkbox

Jordan participates in employer's 401(k) plan

✓ Checked
Box 15

State — TX

Texas has no state income tax

N/A
Box 16

State wages

No state income tax in Texas

N/A
Box 17

State income tax

No state income tax in Texas

N/A
Why is Box 1 ($56,900) so much lower than Jordan's $68,000 salary? Three pre-tax deductions were subtracted before Box 1 was calculated: 401(k) ($7,500) + health insurance ($2,400) + FSA ($1,200) = $11,100 in reductions. $68,000 − $11,100 = $56,900. Jordan only pays federal income tax on $56,900.

Every Box Explained

Box a

Employee's Social Security Number

Your SSN as provided to your employer. Verify this is correct — an error here can delay your refund or cause IRS matching issues. If wrong, contact your employer immediately for a corrected W-2 (Form W-2c).

Used for identity matching — does not appear on your 1040 directly.

Box b

Employer Identification Number (EIN)

Your employer's federal tax ID number — the business equivalent of a Social Security number. You'll need this when entering your W-2 data in tax software.

Entered in tax software for EIN verification. Not on 1040.

Box c

Employer's Name, Address, and ZIP

Your employer's legal name and address. If you moved during the year, this still shows your employer's address, not yours.

Not on 1040. Used for verification purposes.

Box d

Control Number

An optional internal code some employers use to identify W-2s in their payroll system. Many W-2s leave this blank. You do not need it to file.

Not used on 1040.

Box e

Employee's Name

Your legal name as it appears in your employer's payroll system. Must match IRS records exactly. If you recently changed your name (due to marriage, for example) and haven't updated Social Security Administration records, this can cause a mismatch.

Matches your 1040 name field.

Box f

Employee's Address

Your home address as of the time your employer prepared the W-2. If you moved, this may be your old address — that's fine. The IRS uses your address on the 1040, not the W-2.

Not critical — your 1040 address governs.

Box 1

Wages, Tips, Other Compensation

This is your taxable federal wages — the number that goes directly onto your 1040. It is almost always LESS than your gross salary because pre-tax deductions have already been subtracted: traditional 401(k) contributions, health insurance premiums paid through a cafeteria plan (Section 125), FSA contributions, and dependent care FSA funds all reduce Box 1.

→ Form 1040, Line 1a

Box 2

Federal Income Tax Withheld

The total federal income tax your employer withheld from your paychecks throughout the year. This is a credit toward your tax bill. If this number is larger than your total tax liability, you get a refund. If smaller, you owe the difference.

→ Form 1040, Line 25a

Box 3

Social Security Wages

Your wages subject to Social Security tax. This is often HIGHER than Box 1 because traditional 401(k) contributions reduce Box 1 but do NOT reduce Social Security wages. However, Section 125 benefits like health insurance and FSA contributions reduce both Box 1 and Box 3. Box 3 is also capped at the Social Security wage base ($176,100 for 2025).

Not directly on 1040 — used to verify Box 4.

Box 4

Social Security Tax Withheld

Always exactly 6.2% of Box 3 (up to the wage base cap). Your employer matches this 6.2% — so the combined contribution to Social Security is 12.4% of your wages. If you had multiple employers and earned over the wage base, you may have overpaid — you can claim a credit for the excess on your 1040.

→ Used to check for SS overpayment (Schedule 3, Line 11).

Box 5

Medicare Wages and Tips

Your wages subject to Medicare tax. This is usually the same as Box 3 but has NO income cap — all wages are subject to Medicare tax. If you earn over $200,000 as a single filer ($250,000 MFJ), you also owe an additional 0.9% Additional Medicare Tax on earnings above that threshold.

Not directly on 1040 — used to verify Box 6.

Box 6

Medicare Tax Withheld

Always 1.45% of Box 5 (your employer also pays 1.45%, for a combined 2.9%). If your wages exceed $200,000, your employer withholds an extra 0.9% Additional Medicare Tax on amounts above that threshold — but only based on your wages from this employer, not combined household income.

Not on 1040 directly — used to verify total Medicare tax.

Box 7

Social Security Tips

If you work in a tipped job (restaurant, hotel, etc.) and reported tips to your employer, they appear here. Tips are subject to Social Security tax just like regular wages.

Added to Box 3 for SS tax purposes.

Box 8

Allocated Tips

Tips allocated to you by your employer if your reported tips were below the IRS minimum percentage of restaurant sales. This is rare and only applies if you didn't report enough tips. These are taxable income.

→ Form 1040, Line 1b (Tips not included in Box 1).

Box 10

Dependent Care Benefits

The amount your employer paid or reimbursed for dependent care through a Dependent Care FSA or employer-sponsored program. Up to $5,000 ($2,500 if married filing separately) is tax-free. Amounts above those limits are taxable.

→ Form 2441 (Child and Dependent Care Expenses).

Box 11

Nonqualified Deferred Compensation

Distributions from nonqualified deferred compensation plans (not 401(k)s). This box is mainly relevant if you received deferred compensation payments. For most employees, this box is blank.

→ Form 1040, Line 1a if applicable.

Box 12

Various Codes (A–HH)

One of the most important — and most confusing — boxes on the W-2. Up to four codes can appear. Key codes: D = Traditional 401(k) contributions (informational — already excluded from Box 1). E = 403(b) contributions. W = Employer HSA contributions. DD = Employer-sponsored health coverage cost (informational only, not taxable). AA = Roth 401(k) contributions (after-tax, already in Box 1). C = Taxable cost of group life insurance over $50,000.

Varies by code. Code D/E/AA go to retirement plan entries. Code W → Form 8889.

Box 13

Checkboxes

Three checkboxes: (1) Statutory Employee — if checked, you report wages on Schedule C, not Line 1. (2) Retirement Plan — if checked, your ability to deduct a traditional IRA contribution may be limited based on income. (3) Third-Party Sick Pay — sick pay from an insurance company.

Retirement plan checkbox affects IRA deduction limits on Schedule 1.

Box 14

Other

Employers use this catch-all box for various items: state disability insurance (SDI), union dues, educational assistance, nontaxable income, vehicle use, etc. Some Box 14 items are deductible (like SDI in certain states). Tax software will walk you through each one.

Varies by item — follow software prompts.

Box 15

State and Employer's State ID

The two-letter state abbreviation and your employer's state tax ID number. If you worked in multiple states, you may see multiple rows here — and may need to file multiple state returns.

Used on your state tax return.

Box 16

State Wages, Tips, Etc.

Your wages subject to state income tax. Usually the same as Box 1, but can differ — some states don't allow certain pre-tax deductions that the federal government allows.

→ Your state tax return, Line 1.

Box 17

State Income Tax

State income tax withheld from your paychecks. This feeds directly into your state tax return and — if you itemize on your federal return — into Schedule A (capped at $10,000 total with local taxes under the SALT limit).

→ Schedule A, Line 5a (if itemizing).

Box 18

Local Wages, Tips, Etc.

Wages subject to local or city income tax. Common in cities like New York City, Philadelphia, Detroit, and Columbus. Not all employees have entries here.

→ Your local tax return (if required).

Box 19

Local Income Tax

Local or city income tax withheld. Combined with state taxes, subject to the $10,000 SALT cap on Schedule A if you itemize.

→ Schedule A, Line 5a (if itemizing, combined with Box 17).

Box 20

Locality Name

The name of the city or locality (e.g., 'NYC', 'PHILA', 'DET'). This is informational and helps identify which local return to file.

Informational — for local return identification.

Why Box 1 Is Almost Never Equal to Your Salary

The most common point of confusion on a W-2 is the difference between your salary and Box 1. Here's a breakdown of what reduces Box 1:

Deduction TypeReduces Box 1?Reduces Box 3/5?W-2 Code
Traditional 401(k) contributionsYesNoBox 12, Code D
Traditional 403(b) contributionsYesNoBox 12, Code E
Health insurance premiums (Section 125)YesYesReflected in lower wages; info in Box 12 DD
Healthcare FSA contributionsYesYesReflected in lower wages
Dependent Care FSAYesYesBox 10
Roth 401(k) contributionsNo (after-tax)NoBox 12, Code AA
Life insurance over $50K (imputed)Added (taxable)AddedBox 12, Code C

How Your W-2 Maps to Form 1040

Box 1

Form 1040, Line 1a

Wages, salaries, tips

Box 2

Form 1040, Line 25a

Federal income tax withheld

Box 12, Code D/E

Informational on 1040 (no entry)

Pre-tax retirement contributions — already excluded from Box 1

Box 12, Code W

Form 8889 (HSA)

Employer HSA contributions

Box 12, Code DD

No entry — informational only

Employer health coverage cost is NOT deductible

Box 13 (retirement plan checkbox)

Affects IRA deduction limit

If checked, Traditional IRA deduction phases out by income

Box 17 (state tax)

Schedule A, Line 5a

Only if you itemize deductions (SALT cap: $10,000)

Box 10

Form 2441

Dependent care benefits

Common Mistakes When Reading Your W-2

Entering Box 3 or Box 5 instead of Box 1 as taxable wages

Fix: Always use Box 1 for your federal taxable wages on Form 1040, Line 1a. Box 3 and Box 5 are higher because 401(k) contributions don't reduce them.

Ignoring Box 12 codes

Fix: Code DD (employer health coverage) is informational only — don't try to deduct it. Code W (HSA contributions) requires completing Form 8889. Tax software handles this if you enter each code correctly.

Throwing away your W-2 after filing

Fix: Keep your W-2 for at least 3 years (7 if you under-report income). The IRS can audit returns within 3 years of the filing date.

Not checking for errors before filing

Fix: Verify your name, SSN, and employer EIN before filing. A wrong SSN can delay your refund by months. If you spot an error, request a W-2c (corrected W-2) from your employer before filing.

Filing before receiving all W-2s

Fix: If you had multiple jobs, wait for all W-2s. Your employer must provide them by January 31. If you don't receive one, contact the employer — or request a wage transcript from the IRS.

Confusing Box 13 'Retirement Plan' checkbox for a deduction

Fix: This checkbox doesn't give you a deduction — it just flags that you're covered by a workplace retirement plan. If checked, your ability to deduct a traditional IRA contribution phases out at certain income levels.

Assuming Box 2 is your refund

Fix: Box 2 is what was withheld, not what you get back. Your refund (or amount owed) is calculated after subtracting your total tax liability from total withholding across all income sources.

Frequently Asked Questions

Why is Box 1 less than my actual salary?

Box 1 shows your taxable wages after subtracting pre-tax deductions. If you contribute to a traditional 401(k), pay health insurance premiums through your employer's cafeteria plan (Section 125), or contribute to a Flexible Spending Account (FSA), those amounts come out of your paycheck before taxes are calculated — so they reduce Box 1. Example: if your salary is $68,000 and you contribute $7,500 to a 401(k) plus $3,600 in health insurance premiums, your Box 1 would be $56,900.

Why do I have multiple W-2s?

You receive one W-2 from every employer you worked for during the tax year. If you had two jobs, you'll have two W-2s. You report all of them on your 1040 — just add up all Box 1 amounts for Line 1a. A single employer sometimes issues multiple W-2s if you worked in two different states or if they corrected a prior W-2.

Why is Box 3 higher than Box 1?

Traditional 401(k) contributions (Box 12, Code D) reduce your federal taxable wages (Box 1) but do NOT reduce your Social Security wages (Box 3). So if you contributed $7,500 to a 401(k), Box 3 will be $7,500 more than Box 1. This means you still pay Social Security tax on those contributions — you're just deferring income tax on them.

What if my W-2 has an error?

Contact your employer's HR or payroll department immediately. They must issue a corrected W-2 (Form W-2c). Do not file with incorrect information — if you already filed and receive a corrected W-2, you may need to amend your return using Form 1040-X. Employers are required to furnish W-2s by January 31.

I'm a full-time employee but also did some freelance work. Do I get a W-2 for the freelance income?

No. Your employer issues a W-2 for your employment wages. Freelance or contract income (over $600 from a single client) is reported on Form 1099-NEC, not a W-2. You report freelance income on Schedule C and also owe self-employment tax on it.

What does the Box 13 'Retirement Plan' checkbox mean for my IRA?

If this box is checked, the IRS considers you to be covered by a workplace retirement plan. This matters if you also want to deduct a Traditional IRA contribution — your ability to deduct it phases out at lower income levels when you're covered by a workplace plan. If you're single and covered by a workplace plan, the deduction phases out between $79,000 and $89,000 of modified AGI (2025 figures). If unchecked, you can deduct IRA contributions regardless of income.

What if I never received my W-2?

Your employer must provide your W-2 by January 31. If you haven't received it by mid-February, contact your employer first. If that fails, call the IRS at 1-800-829-1040 — they can contact the employer on your behalf. You can also file using Form 4852 (a substitute W-2) based on your last pay stub, though this may delay processing. You can also access a wage transcript at IRS.gov if your employer filed correctly.

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Tax Disclaimer: This article provides general tax information for educational purposes and is not tax advice. Tax laws change annually. The examples above use fictional data. Consult a licensed CPA or enrolled agent for advice specific to your situation.