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Payroll Stack

Methodology and sources

Last updated

What the calculators estimate

The paycheck and take-home pay calculators estimate withholding: what an employer's payroll system takes out of one paycheck. They do not work out your final tax for the year. Your actual tax may differ when you file, and a refund or a balance due is the difference.

Federal income tax

We follow IRS Publication 15-T (2026), Worksheet 1A, the percentage method for automated payroll systems with a Form W-4 from 2020 or later:

  1. Wages for the period (after 401(k) and Section 125 deductions) are multiplied by the pay periods in a year: 52, 26, 24 or 12.
  2. Step 4(a) other income is added.
  3. Step 4(b) deductions are subtracted, and so is $12,900 for married filing jointly or $8,600 otherwise, unless the Step 2 box is checked, in which case nothing is subtracted.
  4. The result is run through the 2026 annual table for the filing status: the standard table, or the Step 2 checkbox table if the box is checked.
  5. The annual amount is divided by the pay periods, Step 3 credits per period are subtracted (not below zero), and Step 4(c) extra withholding is added.

We test this against the IRS's own wage-bracket tables in the same publication: 200 rows across weekly, biweekly, semimonthly and monthly pay and all six filing-status columns agree to within $1.

For reference, the 2026 standard deduction is $16,100 single, $32,200 married filing jointly and $24,150 head of household. Withholding does not subtract it directly; the IRS tables already allow for it.

Social Security and Medicare

  • Social Security: 6.2% of wages up to $184,500 in 2026.
  • Medicare: 1.45% of all wages.
  • Additional Medicare: 0.9% on wages your employer pays you above $200,000 in the calendar year, whatever your filing status.
  • Traditional 401(k) and 403(b) contributions do not reduce these wages. Section 125 health, dental, vision and HSA contributions do.
  • If you enter wages paid so far this year, the paycheck column places the Social Security cap and the Additional Medicare threshold accurately.

Federal figures in effect January 1, 2026 to December 31, 2026; last checked October 1, 2026.

States

Each supported state has its own data file with its rates, the dates they apply, and the sources below. States not listed here are not supported yet and have no calculator page.

Alaska

Alaska has no state income tax on wages.

  • Alaska does not tax wages, so no state income tax is withheld.
  • Employees pay 0.50% unemployment insurance on the first $54,200 of 2026 wages.
  • Unemployment insurance is applied to Social Security wages (an assumption; check your pay stub).

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Arizona

Arizona has a flat 2.5% income tax; employers withhold the percentage you choose on Form A-4 (2% if you have not chosen).

  • Arizona’s income tax rate is 2.5%, but withholding is the percentage you choose on Form A-4: 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0% or 3.5% of gross taxable wages.
  • If you have not filed Form A-4, your employer withholds 2.0%.
  • Form A-4 also lets an employee who expects to owe no Arizona tax choose zero withholding.
  • State wages are assumed to equal federal income tax wages (401(k) and Section 125 contributions excluded).

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Florida

Florida has no state income tax on wages.

  • Florida does not tax wages, so no state income tax is withheld.
  • No employee-paid state payroll deduction is modeled for 2026.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Illinois

Illinois withholds a flat 4.95% state income tax.

  • Illinois withholds 4.95% of wages after subtracting $2,925 for each IL-W-4 line 1 allowance and $1,000 for each line 2 allowance.
  • State wages are assumed to equal federal income tax wages (401(k) and Section 125 contributions excluded).

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Kentucky

Kentucky withholds a flat 3.5% state income tax.

  • Kentucky withholds 3.5% of annual wages after a $3,360 standard deduction.
  • Local occupational license taxes (city and county) are not included.
  • State wages are assumed to equal federal income tax wages (401(k) and Section 125 contributions excluded).

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Michigan

Michigan withholds a flat 4.25% state income tax.

  • Michigan withholds 4.25% of compensation after $5,900 for each exemption on Form MI-W4.
  • City income taxes (Detroit and other cities) are not included.
  • State wages are assumed to equal federal income tax wages (401(k) and Section 125 contributions excluded).

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Nevada

Nevada has no state income tax on wages.

  • Nevada does not tax wages, so no state income tax is withheld.
  • No employee-paid state payroll deduction is modeled for 2026.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

New Hampshire

New Hampshire has no state income tax on wages.

  • New Hampshire does not tax wages, so no state income tax is withheld.
  • No employee-paid state payroll deduction is modeled for 2026.
  • New Hampshire’s tax on interest and dividends was reported repealed from 2025 (not confirmed here); it never applied to wages.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

North Carolina

North Carolina has a flat 3.99% income tax and withholds at 4.09%.

  • North Carolina’s 2026 income tax rate is 3.99%, but employers withhold at 4.09% (the rate plus 0.1%).
  • The NC-4 standard deduction is $12,750 for single and married filers and $19,125 for head of household; each NC-4 allowance is $2,500.
  • Married people each file their own NC-4, so the deduction per paycheck is the same as for a single filer.
  • State wages are assumed to equal federal income tax wages (401(k) and Section 125 contributions excluded).

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Pennsylvania

Pennsylvania withholds a flat 3.07% state income tax on compensation.

  • Pennsylvania withholds a flat 3.07% of compensation, with no allowances or standard deduction.
  • Unlike the federal rules, Pennsylvania taxes your 401(k) and 403(b) contributions.
  • Section 125 health, dental, vision and HSA contributions are treated as not taxable here (an assumption; check your employer’s plan).
  • Local earned income tax and the local services tax are not included.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

South Dakota

South Dakota has no state income tax on wages.

  • South Dakota does not tax wages, so no state income tax is withheld.
  • No employee-paid state payroll deduction is modeled for 2026.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Tennessee

Tennessee has no state income tax on wages.

  • Tennessee does not tax wages, so no state income tax is withheld.
  • No employee-paid state payroll deduction is modeled for 2026.
  • Tennessee’s former Hall tax on investment income ended in 2021; it never applied to wages.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Texas

Texas has no state income tax on wages.

  • Texas does not tax wages, so no state income tax is withheld.
  • No employee-paid state payroll deduction is modeled for 2026.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Washington

Washington has no state income tax on wages.

  • Washington does not tax wages, so no state income tax is withheld.
  • Paid Family and Medical Leave and WA Cares premiums are taken from pay.
  • Both premiums are applied to Social Security wages (an assumption); an employer may choose to pay some of your PFML share.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Wyoming

Wyoming has no state income tax on wages.

  • Wyoming does not tax wages, so no state income tax is withheld.
  • No employee-paid state payroll deduction is modeled for 2026.

In effect January 1, 2026 to December 31, 2026 · last checked October 1, 2026

Not included

  • City, county and school district taxes (for example Pennsylvania local earned income tax, Kentucky occupational taxes, Detroit city tax).
  • Form W-4 from 2019 or earlier (withholding allowances).
  • Supplemental wages such as bonuses paid separately.
  • Daily, quarterly and semiannual pay frequencies.

Rounding and updates

We keep cents throughout and show amounts to the cent. The IRS and some states allow employers to round withholding to whole dollars, so a pay stub may differ by up to a dollar per line.

Federal tables for the next year are normally published in December, and the Social Security wage base in October. We update the data files when they are published, and show the date every figure was last checked.

Disclaimer

Estimates only, not tax, legal or financial advice. Results use 2026 IRS and state withholding formulas as published on the dates shown, and assume the information you enter is complete. Your employer’s payroll and your actual tax return may differ. Local taxes (city, county, school district) are not included unless shown. For your situation, use the IRS Tax Withholding Estimator (irs.gov/w4app) or a tax professional. Payroll Stack is not a payroll provider and is not affiliated with the IRS, any state agency, or any payroll company.