Safe harbor rule
Publication 505 says the required annual payment is generally the smaller of 90% of expected 2026 tax or 100% of 2025 tax when the prior return covers all 12 months.
Apps
Form 1040-ES safe harbor
2026 Estimated Tax Safe Harbor Calculator
Compare the 2026 current-year tax target with the prior-year tax safe harbor, then see the regular quarterly voucher gap after withholding, credits, and payments.
2026 safe harbor signalNext voucher needs attentionThe regular installment method shows a cumulative shortfall.
Tax and payment inputs
Safe harbor estimate
Required annual target$21,000Update the inputs to refresh this result.
Remaining to cover$3,000Update the inputs to refresh this result.
Next voucher gap$0Update the inputs to refresh this result.
Quarterly target$5,250Update the inputs to refresh this result.
Tax after withholding$12,000Update the inputs to refresh this result.
Prior-year target$21,000Update the inputs to refresh this result.
Regular installment checkpoints
| Due date | Cumulative target | Covered so far | Gap |
|---|---|---|---|
| 2026-04-15 | $5,250 | $6,000 | $0 |
High income and farm rules
For higher income taxpayers, the prior-year percentage becomes 110%. Farming and fishing users can select the two-thirds current-year test and the single January 15, 2027 payment timing.