Special Features of the US Tax System – United States
The US tax system has unique features that distinguish it from most other countries: citizenship-based taxation, a complex federal-state-local structure, extensive retirement savings incentives, and no national VAT or sales tax.
Special Features of the US Tax System
The US tax system has unique features that distinguish it from most other countries: citizenship-based taxation, a complex federal-state-local structure, extensive retirement savings incentives, and no national VAT or sales tax.
Citizenship-Based Taxation
The US is one of only two countries that taxes citizens on worldwide income regardless of where they live. US citizens abroad must file tax returns even if earning nothing in the US.
US citizens living abroad can exclude up to $132,900 of foreign earned income from US tax in 2026. Must meet either the Bona Fide Residence or Physical Presence test.
Taxes paid to foreign governments can offset US tax liability dollar-for-dollar. Prevents double taxation. Claimed on Form 1116.
US persons with foreign financial accounts exceeding $10,000 must file FBAR (FinCEN 114). FATCA (Form 8938) required for foreign assets above $50,000 (single) or $100,000 (joint). Severe penalties for non-compliance.
Federal vs. State Taxes
Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, and Wyoming have no state income tax. Significant savings for residents.
State income tax rates range from 0% to 13.3%. High-tax states include California, New York, New Jersey, Hawaii. State taxes are deductible on federal return (SALT cap $10,000).
Some cities levy additional income taxes: New York City (up to 3.88%), Philadelphia, Detroit, and others. Added on top of federal and state taxes.
Retirement Savings Incentives
Employer-sponsored retirement plan. Traditional: pre-tax contributions reduce taxable income, taxed on withdrawal. Roth: after-tax contributions, tax-free withdrawals in retirement.
Traditional IRA: possible tax deduction on contributions. Roth IRA: no deduction but tax-free growth and withdrawals. Income limits apply for Roth contributions and Traditional IRA deductions.
HSA offers tax-deductible contributions, tax-free growth, and tax-free withdrawals for medical expenses. $4,300 individual/$8,550 family limit in 2026. Rolls over year to year.
Sales Tax (No Federal VAT)
State-level sales tax rates vary. Highest base rate: California at 7.25%. Five states have no sales tax at all. Applied at point of sale, not value-added.
Local taxes can add 1-5% on top of state rate. Some areas in Louisiana, Tennessee, and Arkansas have combined rates exceeding 10%.
Most states exempt groceries and prescription drugs. Some exempt clothing (Pennsylvania, New Jersey). Rules vary significantly by state and product category.
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