Estimated Quarterly Tax Calculator United States

If you work for yourself, no employer withholds tax from your pay, so the IRS asks you to pay as you go through four estimated tax payments a year on Form 1040-ES. This estimated tax calculator combines the two federal taxes a self-employed person owes for 2026, self-employment tax and federal income tax, and divides the total into four equal installments so you know roughly what to set aside each quarter.

How self-employment tax is calculated

Self-employment tax is the Social Security and Medicare tax that an employer and employee normally split; working for yourself, you pay both halves. The calculation starts from 92.35 percent of your net profit, which removes the employer-equivalent portion. On that base, Social Security is charged at 12.4 percent (double the 6.2 percent rate) up to the annual wage base of $184,500, and Medicare at 2.9 percent (double 1.45 percent) with no ceiling. The two together are your self-employment tax.

Above the wage base, only the 2.9 percent Medicare portion keeps growing, so two freelancers with very different high profits can owe similar self-employment tax. For lower and middle incomes, self-employment tax at 15.3 percent on most of the profit often exceeds the income tax on the same income.

How the income tax piece works

Income tax is not charged on your full profit. First you deduct half of the self-employment tax, the employer-equivalent share. Then you subtract the standard deduction for your filing status: $16,100 for a single filer, $32,200 for a married couple filing jointly, $24,150 for a head of household, and $16,100 for someone married filing separately. What is left is taxable income, which goes through the graduated federal brackets starting at 10 percent.

Turning the annual total into quarterly payments

The two taxes added together are your annual liability, divided by four for the quarterly payment. The IRS expects roughly even installments, and paying in four parts avoids an underpayment penalty as long as you meet the safe harbor rules. You can also set aside a fixed share of each invoice instead of facing one large bill. If your income is uneven, the annualized income method lets you pay more in strong quarters and less in slow ones, but equal payments are the usual starting point.

The safe harbor

You avoid an underpayment penalty if you pay at least 90 percent of this year’s tax, or 100 percent of last year’s tax (110 percent if last year’s adjusted gross income was over $150,000), whichever is smaller. Many self-employed people base the four payments on last year’s return because that number is already known. If your income rises sharply, you can increase later payments to stay clear of a penalty.

A worked example

Take a single freelancer with $60,000 of net profit in 2026. The self-employment base is 92.35 percent of that, $55,410. Social Security at 12.4 percent is $6,870.84 and Medicare at 2.9 percent is $1,606.89, so self-employment tax is $8,477.73. Half of that, $4,238.87, is deducted along with the $16,100 standard deduction, leaving taxable income of $39,661.13. The brackets give $1,240 on the first band plus 12 percent of the amount above $12,400, or $4,511.34 of federal income tax. Total tax is $12,989.07, four payments of about $3,247.27.

That is about 21.6 percent of the $60,000 profit in federal tax before any state tax. A common rule of thumb is to put 25 to 30 percent of every payment you receive into a separate account, which covers federal tax and leaves room for state tax and slow quarters. In this example the self-employment tax of about $8,478 is larger than the income tax of about $4,511, which catches many new freelancers who budget only for income tax.

Assumptions and limitations

This is a planning estimate, not a filed return. It assumes the standard deduction, that all net profit is subject to self-employment tax, and that you have no other income, credits, withholding, or the Additional Medicare Tax on very high earners. It does not model the qualified business income deduction, retirement contributions such as a SEP-IRA or solo 401(k), the earned income or child tax credits, or state estimated tax, and it uses equal installments instead of the annualized method. The rates, wage base and standard deductions are stored as parameters sourced from the IRS and reviewed each year; for more than a rough figure, check the current 1040-ES instructions or a tax professional.

About This Estimated Tax Calculator

Use this estimated tax calculator to get an instant, accurate estimate. The figures follow official IRS guidance and every rate and threshold is kept up to date for 2026. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.