Where the tax on a paycheck actually comes from

Published 2026-11-05 · Last reviewed 2026-11-06

A paycheck is not one subtraction. It is a fixed order of them, and every line in that order answers a different question: what is set aside before tax, what the income tax is applied to, what FICA is charged on, and what the state takes. $96,500 of gross pay paid twice a month, married filing jointly, with a 4.75% state rate and 1.25% local rate, comes out as $3,171.16 per paycheck and $76,107.75 for the year. This guide is about the assumptions behind those lines, because the number is only as useful as they are.

The order the money leaves

Pre-tax deductions leave first: a traditional 401(k) contribution and Section 125 items such as health, dental and HSA contributions. They reduce the taxable wage itself, which is why they cut the bill twice - once in income tax and once in FICA. Taxable income is then gross pay minus those deductions minus the standard deduction. On this salary the deduction is $32,200 for a joint return, which leaves $64,300.00 taxable.

The federal tax is then charged band by band: $7,220.00 on this salary, which is 7.48% of gross. Nobody pays their top rate on the whole salary - only the dollars inside each band are taxed at that band's rate. FICA is separate and much simpler: Social Security at 6.2% and Medicare at 1.45%, which on these wages is $5,983.00 and $1,399.25, $7,382.25 together (7.65% of gross). FICA is charged on wages after pre-tax deductions, so a 401(k) contribution lowers it too. Then the state and local rates you supplied produce $5,790.00 (6.00%), and what is left is take-home pay.

Those five lines have to add back up. Gross pay is the sum of the tax lines and the take-home figure: $7,220.00 + $7,382.25 + $5,790.00 + $76,107.75 = $96,500.00. The calculator prints that identity on the page rather than asking you to trust it. Take-home is 78.87% of gross here, which is also why the numbers move the way they do when a salary changes.

Two assumptions worth reading before the number

The federal line is the annual bracket ladder, not the IRS percentage-method tables. The whole year is taxed once, on the yearly taxable income, using the 2026 brackets and the 2026 standard deduction. An employer withholds differently: Publication 15-T applies those brackets to each pay period through a table, so bonuses, overtime, a mid-year raise and the elections on your Form W-4 all move a real paycheck away from this figure. The annualised answer is the one that settles at filing; the per-period answer is the one payroll actually prints.

State and local tax are flat rates you supply, so the state line is an order-of-magnitude estimate. Real state systems are progressive, with their own deductions, credits and phase-outs, and a handful of states and cities levy no income tax at all. Replacing the default with your own rate - and reading the result as an estimate rather than a withholding figure - is the honest way to use that line.

Where these numbers come from

• Every figure above is calculated, not copied in. The order of the deductions, the FICA split and the take-home figure come from one shared payroll calculation; the brackets, the standard deduction and the taxable income come from the same tax tables the income tax pages use. The calculator page and this guide use the same calculation, so a change in one shows up in both or in neither.
• Every release automatically checks the math: the FICA rates on wages after pre-tax deductions, the order of the deductions, the identity that the tax lines plus take-home are the gross, and the 2026 bracket edges and standard deduction amounts against the IRS publication.
• The rates themselves are published, not invented. The brackets and the standard deduction follow IRS Revenue Procedure 2025-32 for tax year 2026; Social Security at 6.2% up to the annual wage base, Medicare at 1.45% with no cap, and the 0.9% Additional Medicare tax above the filing-status threshold follow IRS Publication 15 (2026). The sources are listed on the calculator page itself.

What this guide does not cover

It does not read your Form W-4, model state credits or local exemptions, or predict a refund. It does not apply the annual elective-deferral limit to a percentage-based 401(k) entry, so a very high contribution percentage can overstate the deduction. It says nothing about self-employment tax, where the same income is charged both halves of FICA and a different set of deductions applies, and nothing about the tax treatment of equity compensation. Those are separate questions with separate rules, and a page that quietly mixed them in would be wrong on all of them at once.

Work the numbers yourself in the Paycheck Calculator, compare the federal line with the Income Tax Calculator, or see what the W-4 elections change in the W-4 Withholding Calculator.

Explanations and estimates only - not tax, legal or financial advice. Read the full disclaimer.