Cross-Border Tax & Paycheck Comparison

Federal income tax and FICA (Social Security and Medicare) are identical across all 50 states. However, state-level personal income tax varies from 0.0% in nine states (including Texas, Florida, Washington, and Nevada) to a top marginal rate of 13.3% in California and 10.9% in New York State (plus up to 3.876% in New York City). Furthermore, states like California mandate 1.2% State Disability Insurance (SDI) with uncapped wages, while Texas and Florida have zero mandatory disability payroll deductions. On an $150,000 salary, this creates an annual take-home difference of over $12,700 between Texas/Florida and California.

It depends on your income-to-housing ratio. Because Texas and Florida have no personal state income tax, local governments rely more heavily on property taxes to fund school districts and infrastructure. In Texas, effective property tax rates often range between 1.8% and 2.5% of assessed home value, compared to California's Proposition 13 capped baseline of ~1.1% to 1.25%. For higher income earners ($100k+), the income tax savings in Texas or Florida virtually always exceed the higher property tax bill. For lower income earners who own relatively expensive homes, the tradeoff is narrower.

Yes, in many cases, due to New York's aggressive 'convenience of the employer' doctrine (20 NYCRR § 132.18). Under this rule, New York taxes 100% of wages paid to out-of-state remote workers unless the employee can legally prove that working outside New York is an absolute necessity of the employer (e.g. specialized physical laboratory equipment or a registered bona fide employer branch office), rather than for the employee's convenience. In contrast, remote workers employed by California, Washington, or Texas companies face no out-of-state wage withholding on work performed while residing in Texas or Florida.

Under the Tax Cuts and Jobs Act (TCJA), the federal itemized deduction for State and Local Taxes (SALT) is strictly capped at $10,000 per year ($5,000 for married individuals filing separately). This cap primarily penalizes residents of high-tax states such as California, New York, New Jersey, and Massachusetts. In California, a single worker earning $150,000 pays approximately $10,950 in state income tax plus local property taxes, meaning a significant portion of their state tax bill cannot be deducted federally.

Take-home pay in the UK and Ireland is typically lower than in low-tax U.S. states, but the systems fund universal public services directly through payroll taxes. In the UK, basic-rate income tax (20%) kicks in after the £12,570 Personal Allowance, plus 8% Class 1 National Insurance, rising to 40% tax at £50,270. In Ireland, the 20% standard cut-off gives way to a 40% higher marginal rate, plus the Universal Social Charge (USC) and 4% PRSI. In exchange, UK and Irish residents pay zero out-of-pocket employer healthcare premiums and receive comprehensive statutory healthcare via the NHS and HSE.

Traditional 401(k) and 403(b) contributions are made on a pre-tax basis under federal tax code Section 402(g). When you contribute, you reduce federal taxable income and state taxable income in the state where you currently work. Under federal law (4 U.S.C. § 114, the Pension Source Act), states are prohibited from taxing nonresidents on retirement income earned while working in that state. Therefore, if you earn money and contribute to a 401(k) while living in high-tax California or New York, but withdraw that money in retirement while residing in zero-tax Texas or Florida, you pay 0% state income tax on your withdrawals.