Where Do I Find 401k Contributions on W2?

The W-2 form, officially known as the Wage and Tax Statement, is an important document received annually from an employer. It details an employee’s gross wages, taxes withheld, and other compensation information for the tax year. This form is essential for accurately preparing and filing federal, state, and local income tax returns, ensuring that the correct income and tax payments are reported to the appropriate tax authorities. Without a precise W-2, taxpayers would find it challenging to determine their taxable income and claim proper credits or deductions.

Finding Your 401(k) Contributions

Employee contributions to a 401(k) retirement plan are located in Box 12 of your W-2 form. Box 12 is a versatile section on the W-2 used to report various types of deferred compensation and other benefits that may not be included in your taxable wages. Your employer may utilize multiple subsections within Box 12 (12a, 12b, 12c, 12d) to report different amounts.

To identify your traditional 401(k) contributions, look for Code D listed next to a dollar amount in Box 12. This code signifies elective deferrals under a section 401(k) cash or deferred arrangement plan. The amount displayed alongside Code D represents the total sum you contributed to your 401(k) plan from your paycheck during the tax year.

Understanding Box 12 Codes

Code D specifically denotes elective deferrals to a 401(k) plan, including both pre-tax and Roth 401(k) contributions. The amount reported under Code D reflects only the employee’s contributions and does not include any employer contributions, such as matching funds.

Other common codes found in Box 12 relate to different types of retirement plans or deferred compensation arrangements:
Code AA identifies designated Roth 401(k) contributions, which are included in the Code D amount but shown separately for informational purposes.
Code E is used for elective deferrals to a 403(b) plan, often utilized by employees of public schools and certain tax-exempt organizations.
Code F indicates elective deferrals under a 457(b) deferred compensation plan, typically available to state and local government employees.
Code S reports contributions to a SIMPLE IRA.
Code BB denotes designated Roth contributions to 403(b) plans.
Code EE denotes designated Roth contributions to governmental 457(b) plans.

How 401(k) Affects Your Wages

Pre-tax 401(k) contributions impact the taxable wage amounts reported on your W-2. The amount you contribute to a traditional 401(k) plan, identified by Code D in Box 12, directly reduces the figure in Box 1, labeled “Wages, tips, other compensation.” This reduction occurs because these contributions are made with pre-tax dollars, meaning they are not subject to federal income tax withholding at the time of deferral.

Pre-tax 401(k) contributions do not reduce the wages subject to Social Security tax, reported in Box 3, or Medicare tax, reported in Box 5. Consequently, the amounts in Box 3 and Box 5 often appear higher than the amount in Box 1, reflecting that 401(k) contributions remain subject to Federal Insurance Contributions Act (FICA) taxes. In contrast, Roth 401(k) contributions are made with after-tax dollars. As such, Roth contributions do not reduce the wages reported in Box 1, Box 3, or Box 5, as taxes have already been paid on these amounts.