To avoid the federal tax underpayment penalty, pay in enough through withholding and estimated taxes to meet one of three safe harbors: at least 90 percent of the tax you’ll owe this year, 100 percent of the tax shown on last year’s return (110 percent if your prior-year adjusted gross income topped $150,000), or a balance due of less than $1,000 when you file. Hitting any one of them is enough. You choose the target that’s easiest to hit and aim your paycheck withholding or quarterly payments at it.
The Three Safe Harbors
Section 6654 of the Internal Revenue Code lays out the thresholds. Meet any one and no penalty applies:
- Your withholding and estimated payments cover at least 90 percent of your current-year tax.
- Your withholding and estimated payments equal 100 percent of the tax shown on your prior-year return.
- The balance due on your return—total tax minus withholding—is under $1,000.
For most people with steady income, the prior-year figure is the easiest target because it’s a fixed number you already know. Look at last year’s Form 1040, note the total tax, and make sure your withholding plus any estimated payments hit that amount by year-end.1Office of the Law Revision Counsel. 26 USC 6654 – Failure by Individual to Pay Estimated Income Tax
Higher Bar for Higher Incomes
If your prior-year adjusted gross income exceeded $150,000 ($75,000 if married filing separately), the prior-year safe harbor jumps from 100 percent to 110 percent. On a $30,000 prior-year tax bill, that means paying in at least $33,000 during the current year. The 90 percent current-year option and the under-$1,000 threshold don’t change with income.2Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty
When the Prior-Year Option Isn’t Available
The prior-year safe harbor only works if your previous tax year covered a full 12 months and you actually filed a return. Short-year filers and people who didn’t file must rely on the 90 percent current-year test instead.1Office of the Law Revision Counsel. 26 USC 6654 – Failure by Individual to Pay Estimated Income Tax
If You Owed Nothing Last Year
If your prior-year tax liability was zero, no underpayment penalty applies for the current year, no matter how much you owe now. The prior year must have been a full 12-month tax year and you must have been a U.S. citizen or resident throughout. This helps people returning to work after a gap or starting a business after a lean year: your required annual payment under the 100 percent rule is zero.1Office of the Law Revision Counsel. 26 USC 6654 – Failure by Individual to Pay Estimated Income Tax
Adjust Your W-4 to Hit the Target
For wage earners, raising withholding is the cleanest path to a safe harbor. File a new Form W-4 with your employer whenever you want. Step 4(c) lets you specify an extra flat-dollar amount to withhold from each paycheck.3Internal Revenue Service. Form W-4 (2026) Employee’s Withholding Certificate
Estimate the shortfall for the rest of the year and divide by remaining pay periods. A $2,400 gap with 12 paychecks left means $200 per period on line 4(c). No estimated payment vouchers, no quarterly deadlines.
Withholding has a timing advantage that estimated payments don’t: the IRS treats it as paid evenly across the year, even if the extra withholding only kicks in during the last few paychecks. So if you realize in November that you’re underpaid, cranking up your W-4 for the final weeks can retroactively cover earlier quarters.4Internal Revenue Service. Pay As You Go: Withholding and Estimated Taxes
Quarterly Estimated Tax Payments
Income that isn’t subject to payroll withholding—self-employment, dividends, interest, rents, capital gains—generally has to be covered through estimated payments on Form 1040-ES. The form’s worksheet walks you through projecting your income, deductions, credits, and tax, using last year’s return as the starting point. Once you have a total, split it into four equal installments.5Internal Revenue Service. About Form 1040-ES, Estimated Tax for Individuals
You can mix strategies. If you have a day job and side income, extra withholding from the paycheck counts toward the same safe harbor as any estimated payments you send in—the IRS adds them together.
2026 Payment Deadlines
- First quarter (January–March income): April 15, 2026
- Second quarter (April–May income): June 15, 2026
- Third quarter (June–August income): September 15, 2026
- Fourth quarter (September–December income): January 15, 2027
If a deadline lands on a weekend or a D.C. legal holiday, it moves to the next business day.6Internal Revenue Service. Publication 509 (2026), Tax Calendars
How to Pay
The Electronic Federal Tax Payment System (EFTPS) lets you schedule payments up to a year ahead and automate all four installments in one sitting. Sign-in runs through Login.gov or ID.me.7Internal Revenue Service. EFTPS: The Electronic Federal Tax Payment System IRS Direct Pay is a lighter option with no account setup for one-off bank payments.8Internal Revenue Service. Direct Pay With Bank Account Mailing a check with the numbered voucher from the Form 1040-ES package still works.
If You’re Self-Employed
Self-employed filers owe income tax plus self-employment tax for Social Security and Medicare. The Form 1040-ES worksheet handles both. Multiply your net self-employment earnings by 92.35 percent, then apply 12.4 percent for Social Security (on earnings up to $184,500 in 2026) and 2.9 percent for Medicare.9Internal Revenue Service. a href=”https://www.irs.gov/pub/irs-pdf/f1040es.pdf” target=”_blank” rel=”noopener”>Form 1040-ES – Estimated Tax for Individuals10Social Security Administration. Contribution and Benefit Base You can deduct half of your self-employment tax when figuring adjusted gross income on the worksheet, which lowers the income-tax piece of your estimate.
Uneven Income: The Annualized Method
Equal quarterly payments punish anyone whose income arrives in bunches. Seasonal businesses, freelancers with irregular projects, and people who receive one large payment mid-year can use the annualized income installment method instead. You recalculate the required payment at each installment period based on income actually earned by that point. Low-earning quarters produce smaller required payments; a windfall quarter produces a larger one.
To use it, complete Schedule AI on Form 2210 along with Parts I, II, and III of the same form, and attach it to your return.11Internal Revenue Service. Instructions for Form 2210 (2025) The calculation demands a full income, deduction, and credit breakdown for each of the four periods, and many taxpayers who use this route hire a preparer.
Farmers and Fishermen
If at least two-thirds of your gross income for the current or prior year comes from farming or fishing, the schedule collapses to a single payment due January 15 of the following year. You can also skip estimated payments entirely if you file your return and pay the full balance by March 1.12Internal Revenue Service. Farmers and Fishermen
How the Penalty Works If You Miss
The penalty isn’t a flat fine. It’s calculated like interest on each quarterly shortfall, running from that installment’s due date until you pay or file. The rate is the federal short-term rate plus three percentage points, compounded daily. For the first quarter of 2026 the rate is 7 percent per year.13Internal Revenue Service. Interest Rates Remain the Same for the First Quarter of 2026 The IRS resets the rate every quarter.14Internal Revenue Service. Quarterly Interest Rates
Because each quarter runs on its own clock, catching up mid-year cuts the penalty even when you can’t erase it. Paying one installment late doesn’t affect quarters you paid on time.
Waivers When You Already Missed
The IRS can waive part or all of the penalty in a few situations. You request most waivers by filing Form 2210 with your return and attaching an explanation.
- Casualty, disaster, or other unusual circumstance that made timely payment unreasonable. Check box B in Part II of Form 2210 and attach documentation such as police or insurance reports.
- Federally declared disaster. The IRS applies relief automatically for taxpayers in covered areas, so filing Form 2210 usually isn’t necessary. If you’re outside the area but your records or preparer are inside it, call the IRS disaster hotline at 866-562-5227.
- Retirement after age 62 or disability during the current or prior tax year, when the underpayment was due to reasonable cause rather than neglect. Attach documentation of your retirement date and age, or the date the disability began.11Internal Revenue Service. Instructions for Form 2210 (2025)
The IRS reviews each request on its own facts, so approval isn’t automatic outside the disaster-area rule. If you can hit a safe harbor before year-end, that’s still the surest way to keep the penalty off your return in the first place.