Kentucky doesn’t have tax brackets. The state charges a single flat income tax rate on all taxable income, and for the 2026 tax year that rate is 3.5 percent.1Kentucky Revised Statutes. Kentucky Code 141.020 – Levy of Income Tax on Individuals Whether you earn $30,000 or $300,000, the percentage is the same. After subtracting a $3,360 standard deduction and any credits you qualify for, 3.5 percent of what’s left is your Kentucky income tax.
The Flat Rate and How It Keeps Dropping
Kentucky moved to a flat tax in 2018, starting at 5 percent. The rate has fallen in half-point steps since: 4.5 percent for 2023, 4.0 percent for 2024 and 2025, and 3.5 percent beginning with the 2026 tax year. The most recent cut was enacted through House Bill 1 in early 2025.2Kentucky Legislative Research Commission. 25RS HB 1
There is no marriage penalty built into the rate, no phase-outs tied to income level, and no higher tier for high earners. A single flat percentage runs across every dollar of taxable income.
The statute also contains a trigger that can lower the rate further. If the state’s Budget Reserve Trust Fund balance equals at least 10 percent of General Fund revenues at the close of a fiscal year, and General Fund revenues exceed appropriations plus what would have been collected at the prior rate, the rate can drop another half point.1Kentucky Revised Statutes. Kentucky Code 141.020 – Levy of Income Tax on Individuals In theory, sustained surpluses over many years could take the rate all the way to zero.
What You Subtract Before Applying the Rate
Your Kentucky calculation starts with your federal adjusted gross income, modified by Kentucky-specific additions and subtractions. From that you take the standard deduction, which for the 2026 tax year is $3,360.3Kentucky Department of Revenue. Kentucky DOR Announces 2026 Standard Deduction The Department of Revenue adjusts the figure each year for inflation; it was $3,160 for 2024 and $3,270 for 2025.
Kentucky does not offer itemized deductions as an alternative on the state return. Everyone takes the same flat subtraction, regardless of mortgage interest, charitable gifts, or medical expenses.
Retirement Income and Social Security
Retirees get a meaningful carve-out. Kentucky lets you exclude up to $31,110 of qualifying retirement income, covering distributions from private pensions, annuities, profit-sharing plans, and government retirement plans.4Kentucky Revised Statutes. Kentucky Code 141.019 – Calculation of Adjusted Gross Income and Net Income for Taxpayers Other Than Corporations Retirement income above $31,110 is taxed at the regular 3.5 percent rate.
Social Security benefits are fully exempt from Kentucky income tax. They are excluded at the federal level before you ever reach your Kentucky adjusted gross income, so they never enter the state calculation.
Credits That Reduce Your Tax
Deductions lower the income the 3.5 percent rate is applied to. Credits reduce the final tax dollar for dollar. Kentucky offers several.
- A $40 personal credit for each person on the return who is 65 or older, and a separate $40 credit for legal blindness. A taxpayer who is both 65 and blind can claim $80.5Kentucky Department of Revenue. Individual Income Tax
- The family size tax credit, which can erase most or all of a lower-income household’s state tax bill. If modified gross income is at or below 100 percent of the federal poverty threshold for your family size, the credit equals your entire tax. Between 100 and 133 percent of that threshold, it phases down in steps.6Kentucky Revised Statutes. Kentucky Code 141.066 – Family Size Tax Credit
- An education tuition credit worth 25 percent of the federal American Opportunity Credit or Lifetime Learning Credit you claimed, limited to undergraduate studies at Kentucky institutions. Unused amounts carry forward up to five years.5Kentucky Department of Revenue. Individual Income Tax
- A child and dependent care credit equal to 20 percent of the federal credit from Form 2441.5Kentucky Department of Revenue. Individual Income Tax
- A $20 credit for members of the Kentucky National Guard. Military reservists who aren’t in the Guard don’t qualify.5Kentucky Department of Revenue. Individual Income Tax
The family size tax credit is the one households often miss. For 2025, the income ceiling for a family of one was roughly $42,760. The threshold moves with federal poverty guidelines, so check the current year’s instructions when you file. A family that assumes it owes tax may find the credit zeroes out the bill entirely.
Who Has to File a Kentucky Return
Not every resident owes a return. You need to file if your modified gross income exceeds the threshold for your family size and your Kentucky adjusted gross income exceeds the standard deduction threshold for your filing status. The modified gross income cutoffs are:
- Family size of one: more than $15,650
- Family size of two: more than $21,150
- Family size of three: more than $26,650
- Family size of four or more: more than $32,150
These are the most recent published thresholds.7Kentucky Department of Revenue. Do I Need to File a Return If your income falls below the cutoff but Kentucky tax was withheld from your paycheck, file anyway. A return is the only way to get that withholding refunded.
The state deadline matches the federal one. Returns for the 2025 tax year are due April 15, 2026.8Kentucky Finance and Administration Cabinet. Kentucky Tax Filing Season Begins Jan. 26
Local Occupational Taxes Add to the State Rate
The 3.5 percent flat rate is only the state piece. Cities, counties, and school districts across Kentucky levy their own occupational license taxes on wages earned within their borders. Rates typically run from 0.50 percent to 2.50 percent, with a median near 1 percent. Employers generally withhold these taxes based on where you work, not where you live.
That creates a quirk for commuters. You might live in a county with no occupational tax but work in a city that charges 2.25 percent, or straddle two different jurisdictions. The combined bite from state and local income-based taxes often lands in the 4 to 6 percent range when you add the state’s 3.5 percent to whatever applies locally. There is no statewide database of every local rate, so check with your employer or local government if you aren’t sure what you’re paying.
Penalties and Interest if You Miss the Deadline
Late filing is more expensive than most people expect. Kentucky charges a late filing penalty of 2 percent of the tax due for each 30-day period (or fraction of one) that your return is overdue, up to a maximum of 20 percent.9Kentucky Department of Revenue. Penalties, Interest and Fees The minimum penalty is $10 in most cases, or $100 if a jeopardy assessment has been issued.
Interest also accrues on any unpaid balance. For calendar year 2026, the rate is 9 percent.9Kentucky Department of Revenue. Penalties, Interest and Fees It’s set by statute and can’t be waived. Penalty and interest run at the same time, so a return that is both late and unpaid piles up charges fast. If you owe tax but can’t pay in full by April 15, file the return on time anyway. You’ll still owe interest on the unpaid amount, but you avoid the separate late filing penalty stacking on top of it.