Navigating year-end tax forms can leave even the most seasoned accountants scratching their heads, particularly when it comes to recording 401(k) plan contributions. If you are a small to medium-sized company, understanding how these elective deferrals map to Form W-2 is essential for accurate reporting.
Here is a breakdown of how to handle these contributions for the 2026 tax year.
Key W-2 Boxes for 401(k) Reporting
Reporting retirement contributions involves two primary areas of the W-2: Box 1 and Box 12.
Box 1: Wages, Tips, and Other Compensation
This box represents the total amount paid to an employee who is subject to federal income tax.
- Taxable Income Only: Box 1 should only include the taxable portion of an employee’s income.
- Roth Inclusion: If an employee makes Designated Roth contributions, these must be included in Box 1. Unlike traditional 401(k) contributions, Roth amounts are not excluded from taxable wages.
Box 12: Elective Deferrals
Box 12 is where you use specific codes to identify non-taxable (at the time of contribution) deferrals.
- Code D: This is commonly used to report elective deferrals to a section 401(k) plan.
- What to Include: This section records the portion of the salary the employee did not receive immediately because it was deferred. This includes the standard deferral, any “catch-up” amounts for employees age 50 or older, and Roth contributions.
- Consolidated Reporting: For employees 50+, standard elective deferrals and catch-up contributions are reported as a single sum in Box 12 using the appropriate code.
Understanding Contribution Limits
As an employer, it is vital to advise employees of their maximum annual contribution limits. For 2026, the overall limit on annual additions (including elective deferrals and employer matching) is generally the lesser of:
- 100% of the participant’s compensation.
- $72,000 (or up to $83,250 for those age 60 to 63), subject to cost-of-living adjustments.
Maximum Warning: Employers face a deduction limit for their contributions to defined contribution plans. This deduction cannot exceed 25% of the compensation paid or accrued during the year to eligible employees.
Accounting for 401(k) Contributions
To keep your company’s books accurate throughout the year, follow this simplified recording process:
| Action | Recording in Company Books |
|---|---|
| Employee Elects Contribution | Record the election in the HR account with the employee’s signature. |
| Employer Pays Employee | Record the entire gross amount (including plan contributions) as a Payroll Expense. |
| Recording the Payment to the Employee | Debit the Payroll Expense for the full amount (including the deferred amount); credit Cash and the 401(k) Liability accounts. |
| Paying the 401(k) Plan (Employee Contributions) | When the company pays the plan, record the transaction by crediting Cash and debiting the 401(k) Liability account. |
Example Scenario (Tax Year 2026)
Consider an employee in Florida who earned $19,000 in gross payroll. If the employee deferred $9,000 into a traditional 401(k):
- Box 1 would show $10,000.00 as taxable income.
- Box 12 (Code D) would show $9,000 as the non-taxable deferral amount.
The entire $19,000 is recorded (debit) as a payroll expense. (Credits) Credit the cash account for the $10,000 paid directly to the employee at the time of payroll, and credit the other $9,000 to the 401(k) Liability account.
Need more information?
Here are some IRS links you can visit:
Form W2: https://www.irs.gov/instructions/iw2w3
Amounts Employees can contribute: https://www.irs.gov/newsroom/401k-limit-increases-to-24500-for-2026-ira-limit-increases-to-7500#:~:text=Therefore%2C%20participants%20in%20most%20401(k)%2C%20403(b)%2C%20governmental,$11%2C250%20instead%20of%20the%20$8%2C000%20noted%20above.
Limits on Employer deductions: https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-401k-and-profit-sharing-plan-contribution-limits#:~:text=However%2C%20an%20employer’s%20deduction%20for,SIMPLE%2C%20and%20Qualified%20Plans).