Quarterly tax calculator 2026
Estimate the equal payments that may be required to avoid an underpayment penalty. This uses the smaller current-year or prior-year safe-harbor amount, then subtracts expected withholding.
| Estimated 2026 federal tax | $17,101.47 |
| 90% current-year amount | $15,391.32 |
| Prior-year safe-harbor amount | $12,000.00 |
| Required annual amount before withholding | $12,000.00 |
| Expected federal withholding | $0.00 |
| Estimated payments required | $12,000.00 |
Equal-installment dates: April 15, June 15 and September 15, 2026, and January 15, 2027. Uneven income may need the annualized installment method.
2026 federal estimated-tax dates
| Installment | Due date |
|---|---|
| 1st | April 15, 2026 |
| 2nd | June 15, 2026 |
| 3rd | September 15, 2026 |
| 4th | January 15, 2027 |
How the safe-harbor estimate works
In most cases, estimated payments apply when you expect to owe at least $1,000 after withholding and refundable credits, and withholding will be below the smaller of 90% of current-year tax or 100% of prior-year tax. The prior-year percentage becomes 110% when prior-year AGI was above $150,000, or $75,000 if married filing separately.
Seasonal or uneven income may produce different installments under the annualized income installment method. This calculator assumes four equal payments and does not cover farming, fishing, fiscal-year filers or refundable credits.
Sources
- IRS Form 1040-ES (2026) — 92.35% net-earnings factor, 2.9% Medicare and 12.4% Social Security calculation, half-tax deduction, tax schedules, safe-harbor rules and payment dates
- IRS — Self-employment tax — who pays SE tax, Additional Medicare Tax filing-status thresholds and the employer-equivalent deduction
- IRS — About Schedule SE — Schedule SE is used to figure tax due on net earnings from self-employment
Questions
Do I have to pay quarterly taxes if I also have a W-2 job?
Maybe. Federal withholding from the W-2 job counts toward the required amount, so increasing W-2 withholding can reduce or eliminate estimated payments.
Why is the prior-year amount sometimes 110%?
For 2026, the higher-income rule applies when 2025 AGI was over $150,000, or over $75,000 if married filing separately.
Are the four tax periods three months each?
No. The federal due dates are April 15, June 15, September 15 and the following January 15; the payment periods are not equal calendar quarters.