Pre-tax vs after-tax deduction
Pre-tax deductions come out of pay before a given tax builds its wage base; after-tax deductions come out of pay already taxed.
A pre-tax deduction lowers the wages that tax counts, while an after-tax deduction reduces net payNet pay. Net pay is the amount an employee receives by paycheck or direct deposit after every tax and deduction is subtracted from gross pay.Click to open the term without changing any wage base. Treatment depends on the plan and the specific tax, never on the deduction’s name. Pre-tax treatment raises net pay for the same premium and lowers the wages in the affected Form W-2Form W-2. Form W-2 is the annual wage and tax statement you give employees and file with the Social Security Administration, reporting wages paid and taxes withheld.Click to open the term boxes. A deduction that also reduces Social Security wages lowers the earnings credited toward a future benefit. After-tax and post-tax name the same treatment.
Which deductions are usually pre-tax?
Section 125 cafeteria planSection 125 cafeteria plan. A Section 125 cafeteria plan is an IRS-governed plan framework that can allow employees to elect qualifying benefits on a pre-tax basis.Click to open the term deductions are the common pre-tax group. Traditional 401(k)401(k). A 401(k) is an employer-sponsored retirement plan funded through payroll deferrals the employee elects, usually alongside an employer contribution.Click to open the term and 403(b) deferrals are pre-tax for federal income tax but still count as Social Security and Medicare wages. Plan design, law, employee election, and employer configuration all affect the treatment: confirm it at setup, not from a plan name, and confirm any specific plan with a qualified tax professional. A voluntary deduction, one the employee chooses or authorizes, can be pre-tax or after-tax. When you figure disposable earnings under federal garnishmentGarnishment. Garnishment is a legal order requiring an employer to withhold part of an employee’s wages and send it to a creditor, court, or agency.Click to open the term law, you usually cannot subtract voluntary deductions.
- Medical, dental, and vision premiums through a cafeteria plan
- Health savings account contributions through a cafeteria plan
- Health flexible spending accounts
- Dependent care flexible spending accounts
- Traditional 401(k) and 403(b) deferrals, for federal income tax
- Commuter benefits under Section 132, within their monthly limits
- Garnishments
- Child support
- Union dues
- Roth 401(k) contributions
- Disability premiums an employee chooses to pay with taxed dollars
- Repayment of an advance
- Publication 15-B (2026), Employer’s Tax Guide to Fringe Benefits
- Fact Sheet #30: Wage Garnishment Protections of the Consumer Credit Protection Act (CCPA)
General information, not legal or tax advice. Apply current federal and state rules with qualified guidance.