Why did my federal tax go up?

Short answer

A W-4 change, a raise pushing more wages into a higher bracket, or supplemental wages (bonus, RSU vesting) being withheld at the flat 22% supplemental rate.

Educational only — not advice. PayslipIQ USA provides educational guidance only. It is not legal, tax, accounting, payroll, employment, credit, financial, or consumer reporting advice. Results are estimates based on the information you enter or upload and may be incomplete, outdated, or inaccurate. PayslipIQ USA does not verify income, certify payroll accuracy, determine legal violations, or confirm that money is owed. PayslipIQ is independent and not affiliated with the IRS, SSA, U.S. Department of Labor, any state tax agency, employer, or payroll provider. Always confirm with your employer, payroll department, the IRS, your state labor or revenue agency, a CPA, attorney, or another qualified professional before acting.Figures reflect tax year 2025. Last verified 2025-04-01. Rules and limits may change.

How to figure out which cause is yours

Find a recent paycheck where this looked normal.
Compare the two stubs line by line. The Paycheck Comparison tool does this for you.
Identify the line(s) that changed — that is almost always the answer.
Use the Ask Payroll Generator to send a polite question.

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