After-Tax Deduction: What It Means for Employers

What it means in practice

Every paycheck starts with gross pay. Some deductions are excluded from the wages that one or more taxes are figured on; those are pre-tax deductions. Everything else is after-tax: income tax withholding and FICA are figured on wages that still include the amount, and the deduction is subtracted on the way to net pay. "After-tax" describes tax treatment, not the order of lines on a pay stub.

Three kinds of after-tax deductions. Sort every payroll deduction that is not pre-tax into one of three groups, because federal wage law treats them differently. (1) Deductions the employer is legally required to make for a third party, such as a garnishment or child support withholding order (29 CFR 531.39). (2) Voluntary deductions the employee directs the employer to pay to someone else, such as Roth contributions, union dues, charitable gifts and insurance premiums (29 CFR 531.40). (3) Deductions for the employer's own benefit, such as required uniforms or tools, which DOL Fact Sheet #16 says may not cut into the minimum wage or overtime pay.

Designated Roth contributions. The IRS calls a designated Roth contribution "a type of elective deferral that employees can make" to a 401(k), 403(b) or governmental 457(b) plan. The IRS Roth comparison chart says designated Roth contributions "are made with after-tax dollars," while traditional elective contributions "are made with before-tax dollars." The employer "includes the amount of the designated Roth contribution in the employee's gross income," and the contribution is subject to wage withholding. Other points from the IRS Roth FAQs: the law does not allow designated Roth contributions in SARSEP or SIMPLE IRA plans; a plan that offers them must also offer pre-tax elective contributions; there is no income limit; once a contribution is designated as Roth it cannot later be changed to pre-tax; and the employer must separately account for the Roth contributions, gains and losses until the account is fully distributed. A qualified distribution is generally one made after a 5-taxable-year period of participation and on or after age 59 1/2, death or disability.

2026 deferral limits. The IRS sets the 2026 elective deferral limit for traditional and safe harbor 401(k) plans at $24,500, with catch-up contributions of up to $8,000 at age 50 or older, or $11,250 for employees aged 60 to 63. The IRS Roth FAQs say the limit covers the combined amount contributed to designated Roth and traditional pre-tax accounts, in any proportion. An employee in plans of unrelated employers must aggregate all elective deferrals and monitor the total. Beginning in 2026, participants in plans with Roth features must make catch-up contributions on a Roth basis if prior-year wages with the plan sponsor exceeded $150,000.

Garnishments and child support. Court and agency withholding orders are figured on disposable earnings, which DOL Fact Sheet #30 defines as "the amount of earnings left after legally required deductions are made," such as taxes and the employee's share of Social Security and Medicare. For ordinary debts, no garnishment is allowed when weekly disposable earnings are $217.50 ($7.25 x 30) or less; at $290 or more, the maximum is 25%. For child support or alimony, up to 50% may be taken if the worker supports another spouse or child, up to 60% if not, plus 5% for support more than 12 weeks in arrears. Under 29 CFR 531.39, the actual sum paid under a court order counts as wages paid if neither the employer nor anyone acting for it derives any profit or benefit, but withholding above the Consumer Credit Protection Act limit is not treated as paid wages.

Union dues. The Labor Management Relations Act permits an employer to deduct labor organization membership dues only if it has received from each employee "a written assignment which shall not be irrevocable for a period of more than one year, or beyond the termination date of the applicable collective agreement, whichever occurs sooner" (29 U.S.C. 186(c)(4)). For FLSA purposes, 29 CFR 531.40 lists "union dues paid pursuant to a collective bargaining agreement with bona fide representatives of the employees and as permitted by law" among payments that count as wages.

Charitable payroll giving. 29 CFR 531.40 also covers "voluntary contributions to churches and charitable, fraternal, athletic, and social organizations" from which the employer gets no profit or benefit. Employees who deduct the gift need the employer's records. IRS Publication 526 (2025) says an employee who gives by payroll deduction must keep a pay stub, Form W-2 or other employer document showing the date and amount, plus a pledge card from the charity stating that it does not provide goods or services in return. If $250 or more is withheld from a single paycheck, the same records apply; each paycheck's deduction is treated as a separate contribution.

After-tax insurance premiums. Publication 15 (2026) says that under a section 125 cafeteria plan, if an employee "chooses cash or other taxable benefit," the amount is "subject to all employment taxes." Premiums withheld without a cafeteria plan come out of wages that have already been taxed. For FLSA purposes, insurance premiums paid to independent insurers count as wages when the employer "is under no obligation to supply the insurance" and gets no benefit from it (29 CFR 531.40). After-tax premiums can matter later: Publication 15-A (2026) says sick pay "attributable to employee contributions to a sick pay plan made with after-tax dollars" is not subject to Social Security, Medicare or FUTA tax or to income tax withholding, while contributions made pre-tax through a cafeteria plan are treated as employer contributions.

FLSA limits on deductions. Under the Fair Labor Standards Act, wages count as paid only if paid "finally and unconditionally or 'free and clear,'" and the Act is not met where the employee "kicks-back" wages to the employer or another person for the employer's benefit, such as by buying required tools (29 CFR 531.35). In a nonovertime workweek, deductions for tools and similar items are lawful only if the employee still receives the required minimum wage in cash free and clear (29 CFR 531.36(b)). In an overtime workweek, such deductions may not exceed what could be deducted if the employee had worked only the maximum straight-time hours, and the regular rate is figured on the stipulated wage before any deductions (29 CFR 531.37). The employee's share of taxes may be counted as wages (29 CFR 531.38). The federal minimum wage is $7.25 an hour, effective July 24, 2009 (DOL). An arrangement designed to evade the minimum wage is not recognized as valid payment (29 CFR 531.40(b)).

How it works in payroll, step by step. (1) Classify each deduction: pre-tax under a qualifying plan, legally required, voluntary third-party, or for the employer's benefit. (2) Collect the required paperwork, such as the court order, the union dues assignment or the employee's signed authorization. (3) Figure income tax, Social Security and Medicare on wages that include every after-tax amount. (4) Figure any garnishment on disposable earnings, which subtract only legally required deductions. (5) Subtract the after-tax deductions to reach net pay, checking that employer-benefit deductions do not push pay below the minimum wage or into overtime pay. (6) Track Roth deferrals year to date against the combined 2026 limit, and remit amounts to the plan, union, charity or agency.

W-2 reporting. The 2026 General Instructions for Forms W-2 and W-3 list designated Roth contributions under a 401(k), a 403(b) salary reduction agreement or a governmental 457(b) plan among the amounts included in box 1, and say they must be reported in boxes 1, 3 and 5. Box 12 shows them with code AA (401(k)), BB (403(b)) or EE (governmental 457(b)), and Roth catch-up contributions are added to the same code as a single sum. Designated Roth matching or nonelective contributions are reported on Form 1099-R, not in box 12. Box 14a may show other information, labeled; the instructions list union dues, uniform payments, health insurance premiums deducted and "voluntary after-tax contributions (but not designated Roth contributions)" as examples. See our Form W-2 guide.

Recordkeeping. FLSA payroll records must show total additions to or deductions from wages each pay period, "including employee purchase orders or wage assignments," and, in individual records, the dates, amounts and nature of each item (29 CFR 516.2(a)(10)). Those deduction records are kept at least 2 years (29 CFR 516.6(c)). 29 CFR 531.40(b) suggests keeping full records of all assignments and orders and following state rules on signing, witnessing and delivery.

Where states differ. Many states limit deductions more than federal law does. Two examples from official state sources: New York Labor Law 193 allows deductions required by law and deductions "expressly authorized in writing by the employee and are for the benefit of the employee," given voluntarily after written notice of all terms. Its current list includes insurance premiums, pension or health and welfare benefits, charitable contributions, United States bonds, union dues and transit passes; the employer keeps the authorization during employment and six years after; and outside a collective bargaining agreement the employee may revoke in writing, with the deduction stopping within four pay periods or eight weeks, whichever is sooner. The statute shows a narrower version effective November 6, 2028. Washington's RCW 49.52.060 allows deductions required by state or federal law or "expressly authorized in writing in advance by the employee for a lawful purpose accruing to the benefit of such employee," and medical deductions only if the employer derives no financial benefit and records them openly. Check your state labor department before adding a new deduction.

Worked example 1: Roth versus traditional on Form W-2. A Remindax illustration with assumed numbers: an employee earns $60,000 in 2026 wages, has no other deductions and defers $6,000 to the 401(k). As a designated Roth deferral, box 1 is $60,000, boxes 3 and 5 are $60,000, and box 12 shows AA 6000.00. As a traditional deferral, box 1 is $54,000, boxes 3 and 5 stay $60,000, and box 12 shows D 6000.00. Either way, the $6,000 counts toward the $24,500 limit.

Worked example 2: union dues and a garnishment. Assumed numbers: weekly gross pay is $600, taxes withheld are $90, and the employee authorized $30 in Roth deferrals and $10 in union dues. Fact Sheet #30 subtracts only legally required deductions, so disposable earnings are $600 - $90 = $510, not $470. The ordinary-debt limit is 25% of $510, or $127.50, since $510 is above $290.

Worked example 3: minimum wage. Assumed numbers: an employee earns $7.25 an hour for 40 hours, $290. A $10 United Way deduction the employee authorized can count as wages paid under 29 CFR 531.40 if the employer gets no benefit. A $10 deduction for tools the employer requires would cut into the minimum wage and violate 29 CFR 531.35.

Worked example 4: after-tax disability premiums. In Publication 15-A (2026), Edgewood Corporation paid 70% of a group disability policy's cost and employees paid 30%. Alan receives $2,000 a month, so $1,400 of each payment is taxable sick pay and the $600 from employee contributions is excluded.

Questions employers ask. Do after-tax deductions lower Social Security wages? No; they stay in the taxable wage bases, and Roth deferrals appear in boxes 1, 3 and 5 (W-2 Instructions). Can a plan offer only Roth deferrals? No; a plan offering designated Roth contributions must also offer pre-tax elective contributions (IRS Roth FAQs). Do union dues reduce what a creditor can garnish? Usually not; Fact Sheet #30 says voluntary deductions such as union dues usually may not be subtracted. Confirm specifics with a qualified professional.

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