How much tax will I pay in the USA?

Your Social Security number (SSN) is your personal number for work, tax and much of US life. In the US you pay federal income tax, often state and sometimes city income tax, plus FICA, the payroll tax for Social Security and Medicare.

Getting your SSN

An SSN is a bit like a UK National Insurance number, but it is used far more widely: by employers, banks, landlords, phone companies and credit agencies. It is free. In general, only people with permission from the Department of Homeland Security to work can get one.

1. If you are immigrating with a green card, you can ask for an SSN on your immigrant visa application. The card is then posted to the US address you gave, usually within about 3 weeks of arriving
2. Otherwise, start your application online at ssa.gov, then take your documents to a Social Security office or card centre within 45 days
3. If you don’t start online, the SSA suggests waiting 10 days after you arrive before applying, so it can check your immigration record
4. Bring your passport and your I-94 record (your arrival record) showing a status that allows work, and any work permit (EAD). The SSA only accepts originals or copies certified by the issuing agency
5. The card comes by post. Keep it at home rather than in your wallet

You can start work before your number arrives. The SSA says you may work while your application is processed, and your employer adds the number later. See Your first day at work.

ITIN: if you can’t get an SSN

An ITIN (Individual Taxpayer Identification Number) is a tax-only number from the IRS (Internal Revenue Service) for people who need one for US tax but aren’t eligible for an SSN. A common case is a spouse on a dependent visa without work rights who is named on a joint return. You apply on Form W-7, usually attached to your tax return. You can post your documents to the IRS, or apply in person at an IRS office with ITIN services or with a Certifying Acceptance Agent, who can check most documents and hand them straight back. An ITIN doesn’t give you the right to work.

Are you a US tax resident?

US tax residence has its own tests, separate from your visa. You are a US tax resident for a year if you have a green card, or if you pass the substantial presence test:

• You were in the US at least 31 days this year, and
• Days this year, plus a third of the days last year, plus a sixth of the days the year before, add up to at least 183

Some people don’t count days, for example students on F or J visas, and teachers and trainees on J visas, who keep to their visa terms. Residents are taxed on worldwide income, including UK interest and dividends: see Moving money from the UK. Your first year is often a “dual-status” year: non-resident before your residency starting date, resident after it. There are choices that can change this. The UK–US tax treaty and the foreign tax credit help stop the same income being taxed twice. Get advice A cross-border tax adviser is worth it in year one.

Federal income tax rates for 2026

Tax is charged on taxable income: your pay minus pre-tax deductions (such as 401(k) contributions and health insurance premiums) and minus the standard deduction, a fixed tax-free amount. Many people take the standard deduction rather than listing (“itemising”) deductions. There is no personal allowance on top, as the personal exemption is zero.

FICA: Social Security and Medicare

On top of income tax, your employer withholds FICA from your pay, and pays the same again itself:

• Social Security: 6.2% of pay up to $184,500 in 2026
• Medicare: 1.45% of all pay, plus an extra 0.9% withheld on pay over $200,000 in a year

Under the UK–US social security (totalisation) agreement, someone sent temporarily by their employer from one country to the other can, with a certificate of coverage, stay in their home system for up to five years instead. See 401(k) and retirement accounts.

State and city income tax

Most states have their own income tax, and a few cities add one. Here are the places our calculators use. Check the state tax website for your own figures.

For other states, search for the state’s “department of revenue” or “taxation” website. No income tax doesn’t always mean lower costs: states without one raise money in other ways, such as sales and property taxes. Compare in Cost of living.

An example

On a salary of $120,000 (about £90,900), single, living in Austin, with the standard deduction and nothing else: federal income tax is about $17,570 and FICA $9,180, a total of about $26,750 for a full year as a resident. In New York City, state and city tax add several thousand dollars more. Pre-tax 401(k) and health premiums lower the income tax. Try the pay calculator.

Your W-4 and pay stub

On your first day you fill in Form W-4. It tells your employer how much federal tax to withhold (take from your pay). The form no longer uses “allowances”: it asks for your filing status, any second job or working spouse, dependants and other adjustments. If you are a non-resident for tax, there are special instructions (IRS Notice 1392). Many states have their own form too. The IRS has an online Tax Withholding Estimator to check you are on track. Your pay stub (payslip) shows gross pay, each tax, FICA, 401(k) and health deductions, and net pay.

Your tax return

Unlike most UK employees on PAYE, most people in the US file a federal return every year (Form 1040), plus a state return where the state has an income tax. Your employer gives you a Form W-2 after the year ends, showing your pay and tax.

You may also need to file in the UK for the year you leave: see Telling HMRC you’re leaving.