Calculators / Estimated tax
Federal · tax year 2026

Estimated tax safe-harbor calculator

Compare annual prepayment targets and see the gap after withholding and estimated payments.

Last verified October 1, 2026U.S. individual calendar-year filers

Your annual inputs

For calendar-year 2026 Form 1040 filers. Special farming/fishing rules, household employment taxes, nonresident-alien rules, a change between joint and separate returns, and annualized-income or penalty calculations are excluded.

If 2025 tax was zero, choose Yes only if you were a U.S. citizen or resident alien throughout all of 2025 and the zero-tax exception applies. If unsure, consult the IRS instructions before using this tool.Use 2026 Form 1040-ES worksheet line 11c. Include applicable income, self-employment and other taxes; this input is not taxable income.Full-year federal income tax withholding, including expected withholding later in 2026. Do not enter state withholding or payroll Social Security/Medicare taxes.

How the calculation works

The prior-year factor is 110% when 2025 AGI exceeds $150,000, or $75,000 for married filing separately in 2026. At exactly the threshold, the factor is 100%.

The benchmark is the smaller of the available prior-year amount and 90% of estimated 2026 tax after refundable credits. Projected withholding reduces the annual estimated-payment amount; payments already made reduce the remaining top-up. Percentage results are rounded up to the next cent.

If no qualifying 12-month prior-year return is available, only the current-year route is used. The tool does not calculate your tax from income or deductions.

Payment dates still matter

The regular 2026 installment dates are April 15, June 15, September 15, 2026, and January 15, 2027. IRS relief or special rules can change an individual’s deadlines.

This tool does not allocate income or payments among installments, calculate a catch-up payment, or decide whether you owe an underpayment penalty. Uneven income may require the annualized-income method. Review Form 2210 and Publication 505 when payment timing is the question.

Official methodology sources

  1. IRS — 2026 Form 1040-ES
  2. IRS — Underpayment of Estimated Tax by Individuals

Formula follows 2026 Form 1040-ES worksheet lines 11c–14b and the line 12b instructions. This is an annual planning calculation, not a completed return or payment instruction.