Box 1: Taxable wages and tips. Your taxable wages, tips, and other forms of taxable compensation are listed in Box 1 of Form W-2. Taxable fringe benefits will be included (and may be shown on Line 14).
Box 2: Federal income tax withholdings. The amount of federal income tax withholdings from your pay is reported in Box 2 of Form W-2. Enter this amount on Line 64 of Form 1040, Line 40 of Form 1040A, or on Line 7 of Form 1040EZ.
Box 3 and 4: Social Security wages and tax withholdings. Wages subject to Social Security withholdings are shown in Box 3. The total in Box 3 should not exceed $118,500, which is the maximum Social Security wage base in 2015. Elective salary deferrals to a retirement plan are included in Box 3 even though these amounts are not included in Box 1. Social Security taxes withheld from wages and tips are shown in Box 4. The total in Box 4 should not exceed $7,347, which is the maximum Social Security tax in 2015.
Box 5 and 6: Medicare wages and tax withholdings. Wages subject to Social Security tax are also subject to a 1.45% Medicare tax in 2015, which is shown in Box 5. There is no wage base limit for Medicare tax, so the total in Box 5 is not limited to $118,500. Medicare taxes withheld from wages and tips are shown in Box 6. An additional Medicare tax of 0.9% is applied in 2015 for employees who earn over $200,000
Box 10: Dependent care benefits. Reimbursements from your employer for dependent care expenses and the value of employer-provided care services are included in Box 10. Generally, amounts up to $5,000 are tax-free. The tax-free amount will reduce expenses eligible for the dependent care credit. Amounts in excess of $5,000 are included in taxable wages.
Box 12: Elective deferrals to retirement plans. Elective salary deferrals to a 401(k) plan or SIMPLE 401(k) are shown in Box 12 with Code “D”. For example, if you made a pre-tax salary deferral of $10,000 to a 401(k) plan, your employer would enter $10,000 with Code “D” in Box 12. Contributions a Roth 401(k) plan are shown in Box 12 with Code “AA”.
Box 12: Cost of employer-sponsored health coverage. The total cost of your health plan coverage is shown in Box 12 of Form W-2 with Code “DD”. Any amount reported with Code “DD” is not taxable, it is provided for informational purposes only.
Box 12: Travel reimbursements. Reimbursements from your employer for vehicle mileage and business trips are shown in Box 12 with Code “L”. Reimbursements in excess of IRS limits are included in taxable wages.
Box 12: Moving expense reimbursements. Tax-free employer reimbursements for moving expenses are shown in Box 12 of Form W-2 using Code “P”.
Box 12: Employer contributions to health savings account (HSA) or Archer MSA. Employer contributions to a health savings account (HSA) are shown in Box 12 using Code “W”. Total employer contributions to an Archer MSA are shown in Box 12 using Code “R”. Contributions in excess of IRS limits are included in taxable wages.
Box 12: Non-statutory stock option exercised. If you exercised a non-statutory stock option the taxable “spread” (excess of fair market value of stock over exercise price) is shown in Box 12 using Code “V” and is included in taxable wages.
Box 13: Statutory employee. If this box is checked then report your income and deductible job expenses on Schedule C. Earnings are not subject to income tax withholding but are subject to Social Security and Medicare taxes.
Box 13: Retirement plan. If this box is checked then you were an active participant in an employer retirement plan at some point during the year.
Box 14: Taxable fringe benefits and miscellaneous payments. Fringe benefits or deductions from your pay, such as state disability insurance taxes, union dues, educational assistance, and health insurance premiums may be reported in Box 14.
Boxes 15-20: State and local taxes. State wages, state income tax withholdings, local wages, and local income tax withholdings are shown in Boxes 15-20 of Form W-2.