Supplemental income has two very different meanings depending on context. In an employment and tax setting, it means money your employer pays you on top of your regular salary or hourly wages — bonuses, overtime, commissions, severance, and similar payments — that the IRS taxes under a specific set of withholding rules. In the federal benefits setting, it refers to Supplemental Security Income (SSI), a monthly cash program for people who are 65 or older, blind, or disabled and who have very limited income and resources. The two share a word and nothing else, so the rules below are split accordingly.
Supplemental Wages: What Counts
Under federal tax rules, supplemental wages are any compensation your employer pays you that is not your regular hourly or salaried pay. The IRS regulation lists specific examples: bonuses, overtime pay, commissions, back pay, severance pay, reported tips, sick pay from a third-party agent, taxable fringe benefits, and income recognized from nonstatutory stock options or restricted property, among others.1eCFR. 26 CFR 31.3402(g)-1 – Supplemental Wage Payments
Overtime is one of the most common forms. The Fair Labor Standards Act requires employers to pay at least one and a half times your regular rate for every hour you work beyond 40 in a single workweek.2eCFR. Part 778 Overtime Compensation Commission payments, cash-outs of unused vacation or sick leave, back pay from a settlement or payroll correction, retroactive pay increases, and severance all fall into the same category.
How Supplemental Wages Are Taxed
Employers withhold federal income tax on supplemental wages using one of two methods described in IRS Publication 15. Which method applies depends on whether the supplemental amount is identified separately from your regular pay.
When the supplemental payment is separate, or listed as a distinct line item on the same check, the employer can use the percentage method: a flat 22% withheld from the entire supplemental amount, regardless of the tax bracket shown on your W-4. If you receive more than $1 million in supplemental wages during a single calendar year, the portion above $1 million is withheld at 37%.3Internal Revenue Service. Publication 15 (2026), (Circular E), Employer’s Tax Guide – Section: 7. Supplemental Wages
When supplemental pay is lumped in with regular wages and not identified separately, the employer must use the aggregate method. That method adds the supplemental amount to your regular wages for the pay period, treats the total as a single payment, and applies the standard withholding tables tied to your W-4. The aggregate method often takes more out of a single paycheck, because the combined total pushes the calculation into a higher bracket for that period.3Internal Revenue Service. Publication 15 (2026), (Circular E), Employer’s Tax Guide – Section: 7. Supplemental Wages
Supplemental wages are also subject to Social Security tax at 6.2% and Medicare tax at 1.45%, the same rates that apply to regular wages.4Internal Revenue Service. Social Security and Medicare Withholding Rates Social Security tax stops once your total wages for the year reach the annual wage base; Medicare tax has no cap. An additional 0.9% Medicare surtax applies to wages above $200,000 for single filers.
The 22% Is Withholding, Not Your Final Tax
A common misconception is that supplemental wages are permanently taxed at 22%. That rate is only a withholding estimate, meaning the amount taken out of your check to prepay federal income tax. When you file your annual return, all of your income (regular and supplemental) is combined, and your actual tax is calculated using the standard brackets. If the 22% withheld was more than your effective rate on that income, you get a refund. If it was less, you owe the difference.
How Supplemental Wages Appear on Your W-2
Supplemental wages appear on your Form W-2 in Box 1 along with your regular wages; the two are not broken out separately. Federal income tax withheld on the combined amount appears in Box 2.5Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3 – Section: Box 1 If you routinely receive bonuses, commissions, or other supplemental pay, review your W-4 periodically to make sure enough is being withheld across the year. Underpayment can lead to a balance due, and potentially an estimated-tax penalty, when you file.
Supplemental Security Income (SSI)
Supplemental Security Income is a separate federal program, run by the Social Security Administration (SSA), that provides monthly cash to people with very limited income and resources. Despite the similar name, SSI is not funded by Social Security payroll taxes; it comes from general federal tax revenue.6Office of the Law Revision Counsel. 42 USC Chapter 7, Subchapter XVI: Supplemental Security Income for Aged, Blind, and Disabled
Who Qualifies
To be eligible you must fall into one of three groups: age 65 or older, blind, or disabled. You also need very low income and limited assets. For adults, the SSA defines disability as a medically determinable physical or mental impairment severe enough to prevent you from doing your previous work or any other substantial gainful work that exists in the national economy, and the condition must be expected to last at least 12 months or result in death. Children under 18 face a different standard: their impairment must cause “marked and severe functional limitations” lasting at least 12 months or expected to result in death.7Office of the Law Revision Counsel. 42 USC 1382c – Definitions
Unlike Social Security retirement or disability insurance, SSI does not require any work history. Eligibility turns entirely on your financial situation and medical condition.
2026 Payment and Resource Limits
For 2026, the maximum federal SSI payment is $994 per month for an individual and $1,491 per month for a couple.8Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet Your actual payment may be lower if you have countable income.
You must also keep your countable resources below $2,000 as an individual or $3,000 as a couple.8Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet Countable resources include cash, bank accounts, stocks, and other property that could be converted to cash. Your home and typically one vehicle are excluded from this count.
How Income Affects Your SSI Payment
SSI is designed for people with very little income, so nearly every dollar you receive reduces your payment. The formula treats earned and unearned income differently.
Unearned income includes Social Security benefits, pensions, unemployment benefits, interest, dividends, and cash gifts from friends or relatives.9Social Security Administration. Supplemental Security Income (SSI) – Income The SSA ignores the first $20 per month (the general income exclusion) and then reduces your SSI payment dollar-for-dollar for every remaining dollar of unearned income.
Earned income from wages or self-employment gets more favorable treatment. The SSA first applies the $20 general exclusion (if not already used against unearned income), then subtracts an additional $65 earned-income exclusion, and after that counts only half of the remaining earnings against your benefit. So for every extra $2 you earn above those exclusions, your SSI check drops by roughly $1.
Students under age 22 who receive SSI get an even larger break through the Student Earned Income Exclusion. In 2026, qualifying students can earn up to $2,410 per month, and up to $9,730 for the full year, before any of those earnings count against SSI.10Social Security Administration. What’s New in 2026?
State Supplemental Payments
Most states add their own supplement on top of the federal SSI payment. Roughly 44 states and the District of Columbia provide some form of state supplemental payment. A handful of states, including Arizona, Arkansas, Mississippi, North Dakota, Tennessee, and West Virginia, do not.11Social Security Administration. Understanding Supplemental Security Income SSI Benefits The amount and eligibility rules vary widely by state.
In some states the SSA administers the state supplement and sends a single combined check. In others the state runs its own program and issues a separate payment, which means you may need to file a separate application with the state agency.12Social Security. Eligibility for State Supplementary Payments Contact your state’s social services office or local SSA office to find out whether your state offers a supplement and how to apply.
Reporting Requirements and Penalties
If you receive SSI, you must report any change in your income, resources, or living situation to the SSA promptly, and no later than the 10th day of the month after the change happens.13Social Security Administration. Report Changes to Your Situation While on SSI Common reportable changes include starting or stopping a job, receiving a raise, moving, gaining or losing a household member, and changes in bank account balances.
Failing to report on time can trigger both an overpayment, which you will have to pay back, and a penalty deduction from future benefits. The penalties escalate with each offense:
- First failure: $25 deducted from a future SSI payment
- Second failure: $50 deducted
- Third or later failure: $100 deducted each time
These penalty deductions do not apply if you had good cause for the late report or were not at fault.6Office of the Law Revision Counsel. 42 USC Chapter 7, Subchapter XVI: Supplemental Security Income for Aged, Blind, and Disabled Beyond the penalty itself, unreported income can lead to a suspension of benefits or a demand that you repay months of overpayments, which is a much larger financial hit than the penalty deduction alone.