Income Tax in Kentucky
Kentucky (KY) has a flat income tax rate of 4.0% for tax year 2025. The standard deduction is $3,160 for single filers and $3,160 for married filing jointly.
Kentucky runs a low-rate income tax. The top marginal bracket sits in the bottom band of the U.S. state-tax distribution, and the effective rate paid by typical households is correspondingly modest. State revenue mixes income tax with sales and property taxes.
For households comparing Kentucky against other states, the full picture combines income tax (modeled by the calculator) with state and local sales tax, property tax, and any state-specific tax preferences. The compare tool on this site runs a side-by-side total-burden estimate; the per-state pages cover the income-tax piece in detail.
TaxCompare answers state and federal tax questions using the IRS Revenue Procedures and the Tax Foundation state-tax database — the authoritative current-year statutory sources. Every numeric answer on the site uses current-year brackets, deductions, and rates as published by those sources.
Two things to know. First, statutory rates and effective rates are different. A 6 percent state with deductions and credits can produce a lower effective tax than a 4 percent state with no deductions. The compare tool runs effective-rate calculations. Second, multi-state filers (work in one state, live in another) have residency rules the tool does not currently model; the output reflects single-state residence.
How Kentucky Income Tax Works
Kentucky uses a flat-rate income tax structure for tax year 2025: a single rate of 4.0% applies to taxable income above the standard or itemized deduction. Flat-rate states do not stack marginal brackets — every taxable dollar is taxed at the same rate, which simplifies returns at the cost of less progressivity than a bracketed structure.
The state standard deduction in Kentucky is $3,160, applied identically to single and married filers. The standard deduction is subtracted from gross income before bracket rates are applied, so the first $3,160 of income is effectively shielded from state income tax.
Compared to states with progressive brackets, Kentucky's flat structure means a household earning twice as much pays roughly twice as much in state tax (after the standard deduction). High earners pay less than they would under most progressive schedules; low earners typically pay more.
2025 Tax Brackets in Kentucky
| Tax Rate | Taxable Income Range |
|---|---|
| 4.0% | $0+ |
Each bracket rate applies only to taxable income that falls within the bracket range. To see the dollar tax on a specific income, try the income tax calculator.
Standard Deduction
| Filing Status | Deduction |
|---|---|
| Single | $3,160 |
| Married Filing Jointly | $3,160 |
What This Page Cannot Tell You
The brackets and deductions above describe the statutory state-level rules. Your actual state tax liability depends on credits (earned-income credit, child credit, dependent credit), itemized deductions, retirement-income exclusions, local-government taxes (city or county income tax in some states), and federal taxable-income conformity rules. None of those interactions are computed here.
This page is informational and is not tax advice. For filing decisions, consult a qualified tax professional and the official IRS publications and $Kentucky Department of Revenue instructions for tax year 2025. The Tax Foundation publishes annual state-tax-burden comparisons at taxfoundation.org if you want a national context for the Kentucky numbers above.
Frequently Asked Questions
What is the income tax rate in Kentucky for 2025?
Kentucky (KY) has a flat income tax rate of 4.0% for tax year 2025. The standard deduction is $3,160 for single filers and $3,160 for married filing jointly.
Does Kentucky use flat or progressive brackets?
Kentucky uses a flat income tax for 2025 — a single rate of 4.0% applies to all taxable income above the standard or itemized deduction. Flat-rate states do not stack marginal brackets, so every taxable dollar is taxed at the same rate.
What is the Kentucky standard deduction for 2025?
For 2025, Kentucky's standard deduction is $3,160 for single filers and $3,160 for married filing jointly. The deduction is subtracted from gross income before state bracket rates are applied.
Does Kentucky tax Social Security or retirement income?
Social Security and retirement income treatment varies meaningfully across states and changes year to year as state legislatures act. The IRS taxes Social Security at the federal level using a separate worksheet (see Publication 915). For Kentucky's specific treatment, consult the official Kentucky Department of Revenue website. This page is informational; consult a qualified tax professional for advice on your situation.
Where does this data come from?
The brackets and deductions on this page are compiled from official state tax authority publications and from the Tax Foundation's annual state tax data, cross-checked against IRS state tax data where applicable. The 2025 figures reflect statutes in effect as of the most recent update (April 2026). State legislatures sometimes change rates or thresholds mid-year; for filing decisions, always verify against the official Kentucky Department of Revenue publication and consult a qualified tax professional. This site does not provide tax advice.