Oklahoma Estimated Tax Payments (2026)

Do you have to pay estimated taxes in Oklahoma?

Yes. If you're self-employed in Oklahoma and expect to owe $500 or more in Oklahoma income tax for 2026 after withholding, you must make quarterly estimated payments to Oklahoma Tax Commission. That is below the federal $1,000 threshold, so most part-time freelancers owe them too. Oklahoma taxes income at graduated rates up to 4.5%.

When are Oklahoma estimated taxes due in 2026?

Oklahoma's 2026 quarterly payments are due April 15, June 15, September 15, and January 15, in four equal installments, on the same calendar as your federal payments.

• Q1, April 15, 2026

• Q2, June 15, 2026

• Q3, September 15, 2026

• Q4, January 15, 2027

How much should you set aside for Oklahoma estimated taxes?

Plan to set aside 25% to 30% of your net self-employment profit to cover federal and Oklahoma taxes combined, then confirm the exact amount with the calculator above. On $50,000 of net freelance profit, federal self-employment tax alone is about $7,065 (15.3% on 92.35% of your earnings). On top of that you'll owe federal income tax and Oklahoma income tax at graduated rates up to 4.5%.

How do you avoid a Oklahoma underpayment penalty?

To avoid a Oklahoma underpayment penalty, pay the smaller of 70% of your 2026 Oklahoma tax or 100% of your 2025 tax, in four on-time installments. Paying the full amount late doesn't help; each installment has to be on time. You can estimate a federal underpayment penalty here.

What deductions lower your Oklahoma estimated taxes?

Because estimated taxes are based on your net profit, every business write-off you claim lowers what you owe each quarter. Common deductions for 1099 workers, reported on Schedule C, include the home-office deduction, car mileage, phone and internet, software, and supplies. You can also deduct half of your self-employment tax, and the federal Qualified Business Income (QBI) deduction can remove up to 20% of your qualified business income, which flows through to your Oklahoma return in most states.

Keeper's 1099 tax calculator estimates your bill after deductions, and our write-off guides list the deductions for your line of work.

Note: Figures are current for the 2026 tax year and are for planning, not tax advice. Confirm the details with the Oklahoma Tax Commission before you file.

How to file quarterly taxes in Oklahoma

Filing quarterly in Oklahoma means two separate payments each period: one to the IRS for federal tax, and one to Oklahoma Tax Commission for your state taxes. Here’s how to do it.

1. Confirm you need to pay. You owe estimated payments when tax isn’t withheld from enough of your income — 1099 or freelance work, investment income, or other untaxed income. Federal and Oklahoma run separate tests: the state generally requires estimated payments if you expect to owe $500 or more in Oklahoma tax after withholding and credits, subject to its safe-harbor rules.
2. Calculate your federal estimate. Use the Form 1040-ES worksheet (or tax software). Estimate your full-year income, add your federal income tax and self-employment tax, subtract anything already withheld from a paycheck, and split the rest across the year. The estimate at the top of this page gives you a starting number.
3. Calculate your Oklahoma estimate separately. Work out your Oklahoma amount on its own using Form OW-8-ES. Don’t just send part of your federal payment to the state — the Oklahoma calculation is separate, based on your Oklahoma income tax, credits, and any Oklahoma withholding.
4. Pay the IRS. Pay through IRS Direct Pay (or EFTPS) and choose the estimated tax / Form 1040-ES option. Select tax year 2026 and save the confirmation number. This money counts only toward your federal taxes.
5. Pay Oklahoma separately. Make a second payment to OkTAP and select the Form OW-8-ES estimated payment for 2026. Save that confirmation too. This money counts only toward your Oklahoma taxes.
6. Repeat on each deadline. For 2026, federal estimated payments are due April 15, 2026, June 15, 2026, September 15, 2026, and January 15, 2027. Oklahoma uses those same four dates.

Steps reflect 2026 rules and are for planning, not tax advice.