How do self-employed people pay their incomes taxes during the year?

Self-employed individuals typically pay their income taxes through estimated tax payments made quarterly. The IRS requires these payments to cover income tax and self-employment tax, which includes Social Security and Medicare contributions. Self-employed persons calculate their estimated taxes based on expected income and expenses, submitting payments in April, June, September, and January of the following year. They report their income and expenses annually on Schedule C attached to their Form 1040 tax return.