Oklahoma income tax rates range from 0% to 4.5% in 2026 across 4 tax brackets. On top of state tax, residents pay federal income tax (10-37%) and FICA (7.65%). A single filer earning $75,000 in Oklahoma takes home approximately $58,319 after all taxes - an effective rate of 22.2%.
- State income tax: 0% - 4.5% | Standard deduction: $6,350 (single)
- Personal exemption: $1,000 per filer
- Federal income tax: 10-37% on top of state tax
- Oklahoma simplified its income tax to 4 brackets for 2026: the first $3,750 is tax-free, then 2.5%, 3.5%, and 4.5% top rate. The top rate was reduced from 4.75% and the three lowest brackets were eliminated. Social Security income is fully exempt.
How to calculate Oklahoma income tax
Use the calculator above for an instant result. Here is how the calculation works step by step:
- Start with gross income - your total wages or salary before any deductions
- Subtract pre-tax deductions - 401(k) contributions, HSA, health insurance premiums paid pre-tax. This reduces both income tax and FICA
- Apply the federal standard deduction ($15,000 for single in 2026) or your itemized deductions, whichever is larger, to get federal taxable income
- Calculate federal income tax by applying the 2026 bracket rates (10-37%) to your federal taxable income
- Calculate Oklahoma state income tax - subtract the state standard deduction and personal exemption ($1,000) from AGI, then apply the state brackets
- Add FICA taxes - 6.2% Social Security (capped at $176,100) + 1.45% Medicare (uncapped) + 0.9% additional Medicare above $200,000
- Subtract post-tax deductions - Roth 401(k), union dues, etc.
Oklahoma income tax brackets 2026
Oklahoma uses 4 income tax brackets ranging from 0% to 4.5%. The single filer standard deduction is $6,350 plus a $1,000 personal exemption.
| Taxable income (single, 2026) | Rate |
|---|---|
| $0 - $3,750 | 0% |
| $3,750 - $4,900 | 2.5% |
| $4,900 - $7,200 | 3.5% |
| Over $7,200 | 4.5% |
Married filing jointly brackets differ - the income thresholds are higher:
| Taxable income (MFJ, 2026) | Rate |
|---|---|
| $0 - $7,500 | 0% |
| $7,500 - $9,800 | 2.5% |
| $9,800 - $14,400 | 3.5% |
| Over $14,400 | 4.5% |
Source: Tax Foundation 2026.
Federal income tax brackets 2026
Federal income tax applies to all US residents regardless of state. The 2026 brackets (IR-2025-103) are:
| Taxable income (single) | Taxable income (MFJ) | Rate |
|---|---|---|
| $0 - $11,925 | $0 - $23,850 | 10% |
| $11,926 - $48,475 | $23,851 - $96,950 | 12% |
| $48,476 - $103,350 | $96,951 - $206,700 | 22% |
| $103,351 - $197,300 | $206,701 - $394,600 | 24% |
| $197,301 - $250,525 | $394,601 - $501,050 | 32% |
| $250,526 - $626,350 | $501,051 - $751,600 | 35% |
| Over $626,350 | Over $751,600 | 37% |
Federal standard deductions: Single $15,000 | MFJ $30,000 | Head of Household $22,500. The standard deduction is subtracted from gross income before applying brackets.
FICA: Social Security and Medicare (2026)
FICA taxes are separate from income tax and fund Social Security and Medicare. Employees pay:
| Tax | Rate | Wage base |
|---|---|---|
| Social Security | 6.2% | First $176,100 of wages |
| Medicare | 1.45% | All wages (no cap) |
| Additional Medicare surtax | 0.9% | Wages over $200,000 (single) / $250,000 (MFJ) |
Employers match the 6.2% Social Security and 1.45% Medicare contributions, so the total FICA contribution is 15.3% of wages up to the wage base. Self-employed individuals pay the full 15.3% (the "self-employment tax") but can deduct half as a business expense.
Source: IRS Topic No. 751 - Social Security and Medicare Withholding Rates.
Deductions and exemptions in Oklahoma
Federal deductions (2026): The standard deduction is $15,000 for single filers ($30,000 MFJ). Itemize instead if your deductions (mortgage interest, state/local taxes capped at $10,000, charitable contributions, medical expenses over 7.5% of AGI) exceed the standard deduction.
Oklahoma state deductions: The state standard deduction is $6,350 for single filers, plus a $1,000 personal exemption per filer. Married filing jointly filers get a $12,700 state standard deduction.
Key pre-tax deductions that reduce both income tax and FICA taxable wages:
- Traditional 401(k) or 403(b): up to $23,500 in 2026 ($31,000 if age 50+)
- Health Savings Account (HSA): up to $4,300 self-only / $8,550 family in 2026
- Employer health insurance premiums (Section 125 cafeteria plan)
- Flexible Spending Account (FSA): up to $3,300 in 2026
- Traditional IRA: up to $7,000 ($8,000 if 50+), subject to income limits
How Oklahoma compares to other states
Oklahoma's top rate of 4.5% places it near the middle of the range in the US. The national median top state income tax rate is approximately 5-6%. California has the highest at 13.3%; nine states have no income tax at all. See our US income tax comparison map for a state-by-state view.
Frequently asked questions
Does Oklahoma have a state income tax?
Yes. Oklahoma taxes income at rates from 0% to 4.5% for the 2026 tax year.
How much income tax will I pay in Oklahoma on $75,000?
A single filer earning $75,000 in Oklahoma in 2026 would pay approximately:
- Federal income tax: $8,114
- Oklahoma state income tax: $2,830
- Social Security: $4,650
- Medicare: $1,088
- Take-home: ~$58,319 (22.2% effective rate)
Use the calculator above for your exact income, filing status, and deductions.
What is the difference between marginal and effective tax rate?
Your marginal rate is the rate applied to your last dollar of income - the highest bracket you've reached. Your effective rate is total tax divided by gross income - what you actually pay on average. Your effective rate is always lower than your marginal rate in a progressive tax system, because only income within each bracket is taxed at that rate.
Can I reduce my Oklahoma income tax?
Yes. Key strategies: maximize pre-tax retirement contributions (401k, IRA), contribute to an HSA if on a high-deductible health plan, and check whether itemizing deductions exceeds your standard deduction. Pre-tax contributions reduce both income tax and FICA taxes. Contributions to a traditional IRA reduce federal taxable income but may not reduce state income tax in all states.