Self-Employed Quarterly Taxes in 2026: How to Calculate Each Payment
Quarterly estimated taxes are the part of self-employment nobody explains until you have already missed one. There is no withholding on 1099 income, so the IRS asks you to pay as you earn — four times a year, on a calendar that does not match actual quarters. Getting the amount roughly right matters less than paying something on time, because the penalty is charged on what you failed to pay by each date, not on your final April balance.
Who has to pay quarterly
You owe estimated payments if you expect to owe $1,000 or more in tax after subtracting withholding and refundable credits. For most self-employed people that means about $5,000 or more in net profit, since 15.3% SE tax alone crosses the threshold quickly. If a spouse's paycheck withholding is large enough to cover your liability, you can skip estimates entirely.
The 2026 due dates
Q1 (January 1 – March 31) is due April 15, 2026. Q2 (April 1 – May 31) is due June 15, 2026. Q3 (June 1 – August 31) is due September 15, 2026. Q4 (September 1 – December 31) is due January 15, 2027. Note the uneven periods: Q2 covers two months, Q3 covers three. If a date falls on a weekend or holiday it shifts to the next business day.
How each payment amount is calculated
Project your full-year net profit, compute SE tax at 15.3% on 92.35% of it, add federal income tax on taxable income after the standard deduction and half your SE tax, add state tax, subtract any withholding, then divide by four. That is the mechanical version, and it is what a quarterly tax calculator does for you in one pass.
Include state estimates
Most states with an income tax run their own estimated payment system on the same or a similar calendar. Paying federal and forgetting state is a common and expensive oversight.
Round up slightly
Overpaying by a small margin costs you nothing but float and comes back as a refund; underpaying triggers interest.
The safe harbor that removes all guesswork
You avoid the underpayment penalty if you pay at least 90% of the current year's tax or 100% of the prior year's total tax, whichever is smaller. If your prior-year AGI exceeded $150,000, the prior-year figure becomes 110%. Take last year's total tax, divide by four, and pay that regardless of how this year goes — you cannot be penalized even if your income doubles.
The annualized method for uneven income
If you earned nothing in the spring and a fortune in the fall, flat quarterly payments overpay early and underpay late. The annualized income installment method on Form 2210 Schedule AI lets each payment match the income actually earned in that period. It is more paperwork but it is the correct answer for seasonal businesses, creators with viral months, and consultants with lumpy contracts.
How to pay
IRS Direct Pay from a bank account is free and instant; choose 'Estimated Tax' and the correct year. EFTPS works well for recurring scheduled payments. Card payments carry a processor fee of roughly 2%. Save the confirmation number for every payment — you will need the totals when you file.
Worked example: $60,000 profit, single, Arizona
Net profit $60,000. SE tax on 92.35% ($55,410) is about $8,478, half deductible. Taxable income after that deduction and the $16,100 standard deduction is roughly $39,661, giving about $4,450 of federal income tax. Arizona adds roughly $1,000. Total near $13,930, so each quarterly payment is about $3,480. If withholding from a part-time W-2 job already covers $4,000 of that, the quarterly figure drops to about $2,480.
What the penalty actually costs
The underpayment penalty is interest, charged per quarter on the shortfall from the date it was due until it is paid, at a rate that has recently run around 7% to 8% annualized. Missing a $3,000 payment for six months costs on the order of $110 — annoying rather than ruinous, but entirely avoidable.
If you missed a quarter
Pay as soon as you can; the interest stops accruing on the day the money arrives. Do not wait for the next due date and do not skip ahead. Then either raise the remaining payments or, if you have a W-2 job, increase withholding — withholding is treated as paid evenly across the year and can retroactively cure an earlier shortfall in a way estimated payments cannot.
Adjust your estimate mid-year
Recalculate before each due date using year-to-date actuals rather than January's optimism. A calculator run in September with real numbers beats a projection made in April, and Q4 is your last chance to correct course before filing season.
Bookkeeping that makes this painless
Move a fixed percentage of every client payment into a separate tax savings account the day it arrives. When the due date comes, the money is already there and the payment is a two-minute task rather than a cash-flow crisis.
Frequently asked questions
+How do I calculate self-employed quarterly taxes for 2026?
Project annual net profit, add 15.3% SE tax on 92.35% of it to federal income tax on income after the standard deduction and half the SE tax, add state tax, subtract withholding, and divide by four.
+What happens if I skip a quarterly payment?
The IRS charges an interest-style underpayment penalty on the shortfall from that due date until you pay. Paying late is much cheaper than not paying at all.
+Can I just pay everything in April instead?
You can, but the penalty applies to each quarter you underpaid along the way. Paying the full amount in April does not undo three missed deadlines.
+What is the safe harbor for estimated taxes?
Paying 100% of your prior-year total tax — 110% if your prior-year AGI was over $150,000 — protects you from the penalty no matter how much this year's income grows.
+Do I pay state estimated taxes too?
In most states with an income tax, yes, on a similar calendar. States without income tax, such as Texas and Florida, require nothing.
+Are quarterly payments the same amount each time?
They can be, but if your income is seasonal the annualized income installment method lets you pay based on each period's actual earnings instead.
About the author
Javed Niamat · Founder & Editor, GigTax
Javed Niamat founded GigTax to make self-employment tax math understandable for rideshare drivers, delivery couriers, creators and freelancers. He builds and maintains every calculator on this site and writes the guides that explain the numbers behind them.
Related calculators
- Self-Employed Tax EstimatorEstimate federal, SE, and state tax for your full 1099 year.
- Side Hustle Tax CalculatorEstimate tax on side-gig 1099 income stacked on your W-2.
- Freelancer Quarterly Tax CalculatorForm 1040-ES quarterly payments for freelance 1099 income.
- Gig Worker Tax CalculatorFederal + SE + state tax and mileage for any mix of gig platforms.
Related guides
- Quarterly Tax Deadlines Explained: The 2026 Form 1040-ES CalendarThe 2026 IRS quarterly tax deadlines for 1099 workers: April 15, June 15, September 15, and January 15, 2027. Safe-harbor rules, penalties, and how to pay.
- Independent Contractor Quarterly Taxes: How Much, When, and How to Pay in 2026How independent contractors calculate, schedule, and pay quarterly estimated taxes in 2026 — safe harbor rules, 1040-ES math, and penalty math explained.
- How to Avoid IRS Penalties as a Freelancer in 2026The 6 IRS penalties that hit freelancers — underpayment, late-filing, late-payment, accuracy, SE tax, and 1099 mismatch — and exactly how to avoid every one in 2026.
- How to Estimate Self-Employment Tax: A 2026 WalkthroughEstimate your 2026 self-employment tax in 5 steps: the 92.35% × 15.3% formula, quarterly split, prior-year safe harbor, and how to pay the IRS in under 2 minutes.