Oklahoma tax guide

Oklahoma taxes for self-employed workers in 2026

Oklahoma uses a 70% test, which is more forgiving than the federal 90%.

Published by Cadus Labs LLC · Last updated November 9, 2026 · How we write these guides

Based on the Oklahoma Tax Commission's 2026 Form OW-8-ES-SUP and other guidance from the state's tax agency.

Oklahoma estimated tax payments for 2026

You generally have to make quarterly payments if you expect your Oklahoma tax to exceed your withholding by $500 or more, and your withholding will be less than the smaller of 70% of this year's tax or last year's liability.

The form is Form OW-8-ES, and you can generally pay online instead of mailing it.

2026 Oklahoma estimated tax due dates for calendar-year filers
PaymentDue
First paymentApril 15, 2026
Second paymentJune 15, 2026
Third paymentSeptember 15, 2026
Fourth paymentJanuary 15, 2027

If your income is seasonal, the annualized method on Form OW-8-ES-SUP may lower a payment.

Your federal tax comes first

Wherever you live, self-employed income is subject to federal income tax and self-employment tax. A single filer with $60,000 of net profit and no other income owes about $12,037 in federal tax for 2026, or 20% of profit, before any state or local tax.

Federal estimated payments are due April 15, June 15, and September 15, 2026, and January 15, 2027. Use our 1099 tax calculator to run your own numbers.

Recordkeeping checklist

Set aside for federal and state tax from every payment you receive.
Make federal and state estimated payments if you expect to owe enough.
Keep receipts and a mileage log for everything you deduct.
Put each Oklahoma payment date on your calendar.

Free tools for this

Calculator

1099 and Self-Employment Tax Calculator

Enter your 1099 income and business expenses to estimate self-employment tax, federal income tax, and what to set aside each quarter. No sign-up, and nothing you type is saved.

Calculator

Quarterly Tax Set-Aside Calculator

Turn expected profit into a practical tax savings target, then use Cadus to keep income, expenses, deductions, receipts, and reports organized.

Template

Quarterly Tax Savings Worksheet

Use this worksheet to turn expected monthly profit into a practical tax savings target before estimated tax due dates arrive.

Template

Business Expense Log Template

Copy this table to start organizing business purchases, receipt proof, categories, and business purpose before moving records into Cadus.

Official sources

the Oklahoma Tax Commission's 2026 Form OW-8-ES-SUPOklahoma: 2025 Form OW-8-ES

Related guides

Self-employment tax guide

Self-Employment Tax

The self-employment tax rate is 15.3%. See who pays, how the 2026 wage base works, the deduction for half the tax, and a worked example.

Estimated tax guide

Quarterly Estimated Taxes

2026 estimated tax due dates, who has to pay, how to avoid the penalty, and a worked example for a self-employed worker earning $60,000.

Schedule C education

Schedule C Expense Categories

Every Schedule C expense line in plain English: what goes on each one, what doesn't, and the records to keep for self-employed workers.

Oklahoma Taxes FAQ

When do I have to pay Oklahoma estimated tax?

You generally have to make quarterly payments if you expect your Oklahoma tax to exceed your withholding by $500 or more, and your withholding will be less than the smaller of 70% of this year's tax or last year's liability.

When are Oklahoma estimated payments due in 2026?

April 15, 2026, June 15, 2026, September 15, 2026, and January 15, 2027.

Cadus educational content is not tax, legal, or accounting advice. Tax rules can change, and individual facts matter. Review official guidance or speak with a qualified tax professional before filing.