Complete Tax Guide

How the US Tax System Works

The United States uses a progressive federal income tax system, meaning higher income is taxed at higher rates — but only the income within each bracket is taxed at that bracket's rate. Many people misunderstand this and believe that earning more money can somehow result in less take-home pay. That's not how it works.

For 2025, the seven federal income tax brackets range from 10% on the first ~$11,925 of taxable income (for single filers) to 37% on income above $626,350. Taxable income is calculated after subtracting either the standard deduction ($14,600 for single filers in 2025) or itemized deductions — whichever is greater.

The Difference Between Marginal and Effective Tax Rate

Your marginal tax rate is the rate on your last dollar of income. Your effective tax rate is what you actually pay as a percentage of your total income. For a single filer earning $75,000, the marginal rate is 22% but the effective federal rate is closer to 13–14% after the standard deduction. Understanding this distinction prevents many common financial planning mistakes.

Self-Employment and Freelance Taxes

If you're self-employed, a freelancer, or an independent contractor, you owe self-employment (SE) tax in addition to income tax. SE tax is 15.3% — covering both the employee and employer shares of Social Security (12.4%) and Medicare (2.9%). However, you can deduct half of SE tax from your income, and qualifying freelancers may deduct up to 20% of business income under the Qualified Business Income (QBI) deduction. Quarterly estimated tax payments are required to avoid penalties.

Capital Gains: Short-Term vs. Long-Term

Capital gains tax rates depend entirely on how long you held the asset. Assets held for one year or less are short-term gains taxed as ordinary income (up to 37%). Assets held longer than one year qualify for preferential long-term capital gains rates: 0%, 15%, or 20% depending on your income level. For 2025, the 0% rate applies up to $47,025 for single filers — meaning strategic timing of asset sales can dramatically reduce your tax bill.

Cryptocurrency Taxes

The IRS treats cryptocurrency as property, not currency. Every taxable event — selling crypto, trading one coin for another, using crypto to buy goods or services — triggers a capital gains calculation. Mining income and staking rewards are taxed as ordinary income at their fair market value when received. Record-keeping is critical; cost basis tracking across exchanges and wallets is a major challenge for active crypto users.