Your employer doesn't guess how much federal tax to take out of each paycheck. They look it up — in the federal withholding tax table published by the IRS in Publication 15-T, or they let payroll software apply the same math. Take a single filer earning $68,000 a year, paid biweekly — $2,615.38 per check. The table-driven answer is about $235.77 of federal withholding per paycheck, on top of Social Security and Medicare. This guide shows exactly where that number comes from.
Once you know how to read one, you can check whether your own withholding looks sane and see exactly which lines of your W-4 change the result. Everything below uses 2026 figures — the $16,100 single-filer standard deduction and the 10%–37% federal brackets — the same numbers our calculators use.
Every January the IRS publishes updated withholding tables in Publication 15-T, Federal Income Tax Withholding Methods. The tables aren't tax law — they're a lookup system that converts your pay, filing status, and Form W-4 entries into a per-paycheck dollar amount. Your employer (or their payroll provider) gets there one of two ways.
The wage-bracket method is the printed-table version. Separate tables cover weekly, biweekly, semimonthly, and monthly payrolls, with separate columns for single, married filing jointly, and head of household. Find the row containing your wage range, slide across to your filing-status column, read off the withholding. It's fast, which is why small employers still use it — but the printed tables run only up to a set wage ceiling.
The percentage method does the same job with arithmetic. Payroll annualizes your pay, subtracts an amount standing in for the standard deduction and your W-4 adjustments, runs the rest through the 10%–37% brackets, divides back down by pay periods, and applies dependent credits and extra withholding. Almost all payroll software uses this method, and it's required once wages pass the wage-bracket ceiling or you use line 4(c). A few dollars of difference between methods is just rounding in the printed table.
The IRS PDF looks intimidating — page after page of wage ranges — but reading one takes four steps. Step 1: pick the table for your pay frequency. A biweekly and a semimonthly paycheck of the same size withhold differently, because biweekly means 26 checks a year and semimonthly means 24. Step 2: find the row for your gross wages this pay period. Rows are narrow bands, something like "at least $2,600 but less than $2,620," and the cell assumes wages mid-band.
Step 3: adjust for your W-4 first. Checking the multiple-jobs box in Step 2, or entering other income in Step 4(a), raises the taxable wages used for table purposes; deductions in Step 4(b) lower them. A plain W-4 — Steps 1 and 5 only — uses wages as-is. Step 4: read across to your filing-status column, subtract any dependent amount from Step 3 (converted per paycheck), and add any extra withholding from line 4(c).
One more thing: the cell covers federal income tax only. Social Security (6.2% on wages up to $184,500 in 2026) and Medicare (1.45% on every dollar, plus 0.9% over $200,000) are figured separately and stacked on top. When your stub shows a bigger bite than the table suggests, FICA is almost always the difference.
Here's the math for the paycheck from the top of this page — single filer, $68,000 a year, paid biweekly, plain W-4. Each gross paycheck is $2,615.38 ($68,000 ÷ 26). The percentage method follows the same steps payroll software runs every payday:
1. Annualize the pay: $2,615.38 × 26 = $68,000. 2. Subtract the standard deduction built into the tables: $16,100 for a single filer in 2026, leaving $51,900 of taxable income. 3. Run it through the brackets: 10% on the first $12,400 is $1,240; 12% on the next $38,000 is $4,560; 22% on the remaining $1,500 is $330 — $6,130 of annual federal tax. 4. Divide back: $6,130 ÷ 26 = $235.77 withheld per paycheck.
That $235.77 is federal income tax only. The same stub also loses $162.15 of Social Security (6.2%) and $37.92 of Medicare (1.45%) — about $435.84 in federal deductions before state tax, 401(k), or health premiums. The biweekly wage-bracket table lands within a dollar or two of $236; the printed table rounds to whole dollars, the percentage method keeps the cents.
Pay frequency moves the per-check number more than people expect. Pay that same $68,000 semimonthly — 24 checks of $2,833.33 — and the same $6,130 divides by 24: $255.42 per check. Same salary, same annual tax, bigger slice only because there are fewer paychecks. To run your own numbers you need gross pay per period, filing status, and whatever you entered on your W-4 beyond Steps 1 and 5 — or let the tax withholding calculator do the annualizing.
The most common complaint is that the tables "over-tax" big paychecks. What actually happens is annualization: the tables treat every paycheck as if you earn that much all year. A heavy overtime week pushes your $2,615 check to $3,400, payroll annualizes that to $88,400, and part of the check gets withheld as if it sits in the 22% bracket. You are not being taxed extra — you're being withheld extra, and the difference comes back as a refund, or shrinks what you owe, when you file.
Bonuses work differently. Most employers skip the tables for bonuses and use the flat 22% supplemental rate instead (37% over $1 million a year), then add FICA. A $5,000 bonus loses $1,100 to federal withholding before Social Security and Medicare. That's withholding, not a special bonus tax rate — on your return the bonus is taxed at your normal marginal rate. Our bonus tax calculator shows the split.
Mid-year changes look erratic too. Start a job in July and withholding still annualizes as if you'd earned that rate since January — the tables have no memory of other jobs unless you declare the income in Step 4(a). Cross the $184,500 Social Security wage base and take-home jumps, because the 6.2% line switched off, not because the table changed. And two jobs at once is the classic trap: each employer shelters the standard deduction on its own — $32,200 instead of $16,100 — unless you check the box in Step 2.
The table gives a starting number; your W-4 bends it in five predictable ways. Step 2, the multiple-jobs checkbox, switches payroll to a higher-rate calculation that assumes income split across jobs, raising withholding on each check. Step 3, dependents, subtracts a credit — $2,000 per qualifying child under 17 in 2026 — converted per paycheck: on biweekly pay, one child lowers federal withholding by about $76.92 per check ($2,000 ÷ 26). Step 4(a), other income (freelance work, interest, dividends), raises the wage base. Step 4(b), deductions — itemized deductions above the standard deduction — lowers it. And Step 4(c), extra withholding, is the blunt instrument: a flat dollar amount added to every paycheck on top of the table's answer.
Concrete tune-up: say you owed $1,040 on last year's return and nothing else changed. Paid biweekly, that's a $40-per-check shortfall. Write $40 on line 4(c) of a fresh W-4 and next year's shortfall is covered almost exactly ($40 × 26 = $1,040). No table lookup required on your end — your employer adds it after the table does its work.
Exempt status switches the tables off entirely. Had no federal tax liability last year and expect none this year? Writing EXEMPT on the W-4 stops federal withholding (FICA still applies; the claim expires each February 15 unless renewed). Fine for a student with a small summer job — a fast route to a bill plus penalty for anyone with real income.
Everything above is the federal system. Most states run a parallel one — own tables or a flat percentage, driven by a state W-4 or the federal form. The same $68,000 withholds nothing for state tax in Texas or Florida (two of nine states with no wage income tax), while California, New York, and Illinois each take their own slice. Fifty variations is why the take-home pay calculator asks for your state first.
A five-minute check catches most problems. Annualize one stub — federal withholding times pay periods per year — and compare it with a rough annual tax computed as in section three: gross pay minus the $16,100 standard deduction ($32,200 married filing jointly), through the 10%–37% brackets. Thousands above means a big refund is coming; adjust your W-4 to keep the money during the year. Thousands below — common with two jobs or side income — means a balance due; fix it with Step 2 or line 4(c) while paychecks remain.
Run that check after any raise, new job, marriage, or new baby, and once each fall. The tables themselves are mechanical and reliable; it's the inputs — your W-4, your pay frequency, your second job — that drift out of date. The table is never really wrong. It's just answering the question your W-4 asked it.
In IRS Publication 15-T, Federal Income Tax Withholding Methods, published each year at irs.gov. It holds the wage-bracket tables for weekly, biweekly, semimonthly, and monthly payrolls, plus the percentage-method tables payroll software uses — the source document behind every pay stub's federal line.
Usual causes: new IRS tables in January, a new W-4 on file, a pay-frequency change, or a pre-tax deduction like a 401(k) contribution or health premium changing the taxable wages the tables apply to. If none of those happened, ask payroll — a coding error is possible, and it's easier to fix mid-year than after your W-2 is printed.
No. The tables produce withholding — a per-paycheck prepayment, not your final tax. Your actual bill is computed on your return from total income, deductions, and credits. Withholding above the bill comes back as a refund; withholding below it means a balance due, plus a possible underpayment penalty if you fall outside the IRS safe harbors (generally 90% of this year's tax or 100% of last year's, 110% for higher earners).
At most mid-size and large employers, the percentage method — it's what payroll software computes, and it's required for higher wages and for extra withholding requested on line 4(c) of the W-4. Small employers running payroll by hand may still use the printed wage-bracket tables. For the same paycheck the two methods land within a dollar or two of each other, so you usually can't tell from the stub alone.