Kentucky’s individual income-tax standard deduction will rise by $110 to $3,470 for tax year 2027, giving taxpayers and payroll administrators a new figure to use in planning for the coming year. The Kentucky Department of Revenue announced the inflation adjustment this month and said it will be incorporated into the state’s 2027 tax forms.
The new amount is 3.3% above the $3,360 deduction in effect for 2026. The department’s announcement does not change filing deadlines or determine a taxpayer’s final liability by itself. Instead, the standard deduction reduces the Kentucky income subject to tax for individuals who elect to use it rather than itemize deductions.
Kentucky law requires the department to update the deduction annually. Under KRS 141.081, the prior-year amount is multiplied by an inflation factor based on the nonseasonally adjusted U.S. city-average Consumer Price Index for all urban consumers. The formula compares two 12-month periods ending in July, and it prevents the deduction from falling when the calculated inflation factor is below one.
The statute also establishes important limits. The standard deduction is optional for individuals and replaces itemized deductions when selected. It is not available for a short tax year caused by an accounting-period change or for fiduciaries. Married taxpayers living together must apply the election consistently when one spouse’s income is determined without the deduction.
The 2027 increase continues a series of annual inflation adjustments. Kentucky set the deduction at $3,270 for 2025 and raised it by $90 to $3,360 for 2026, according to the department’s prior-year notice. The latest $110 increase is therefore larger in dollars than the previous adjustment, though it remains modest relative to most household income.
Across the state budget, the deduction has a much larger cumulative effect. Kentucky’s official tax analysis estimated that the provision would reduce revenue by $166.2 million in fiscal 2026, $169.9 million in fiscal 2027 and $173.4 million in fiscal 2028. Those projections predated the newly announced 2027 amount but show the scale of the policy across all eligible returns.
For scale, a $110 increase in a deduction does not produce a $110 tax cut. The change affects taxable income, so the benefit depends on the tax rate and the taxpayer’s circumstances. Kentucky’s official 2026 withholding formula uses a 3.5% individual rate and the $3,360 deduction. If the same rate applied in 2027, the additional $110 deduction would reduce tax by about $3.85 for an eligible filer. The Revenue Department’s deduction notice, however, does not announce a 2027 rate, so taxpayers should wait for the state’s updated forms and withholding guidance before calculating final amounts.
The practical effect arrives first for employers, payroll providers and taxpayers preparing 2027 estimates. They should use the new $3,470 figure only for Kentucky calculations for the 2027 tax year, while continuing to use the applicable current-year forms for 2026 filings and withholding. Federal deductions are separate and do not replace Kentucky’s state-specific rules.
