If you live or work in St. Louis, you face two separate income-based taxes. Missouri charges a state income tax that tops out at 4.70% for the 2026 tax year, and the City of St. Louis charges a flat 1% earnings tax on wages and other compensation. They are filed on different forms, through different portals, and carry different penalties. The first thing to settle is whether you’re actually inside the City, because St. Louis City and St. Louis County are separate jurisdictions and the 1% earnings tax applies only within City limits.
Missouri Income Tax Rates for 2026
Missouri uses a graduated scale. Rates start at 1.5% on the first $1,000 of Missouri taxable income and climb through several brackets to the top rate of 4.70%, which applies to all taxable income above $9,191 for 2026.1Missouri Revisor of Statutes. Missouri Revised Statutes 143.011 – Resident Individuals, Tax Rates, Rate Reductions, When2Missouri Department of Revenue. 2025 Individual Income Tax Year Changes The top rate has been dropping over the past few years through a revenue-triggered reduction mechanism, down from 4.95% in 2023.
The standard deduction for 2026 is $15,750 for single filers and $31,500 for married couples filing a combined return.2Missouri Department of Revenue. 2025 Individual Income Tax Year Changes Your Missouri return begins with your federal adjusted gross income, then applies Missouri-specific deductions and exemptions. Because the state uses rolling conformity with the federal Internal Revenue Code, federal changes to deductions and income definitions generally flow through to your state return automatically.
Who Owes Missouri Income Tax
Missouri treats you as a resident if you are domiciled in the state, or if you keep permanent living quarters here and spend more than 183 days in Missouri during the tax year.3Missouri Department of Revenue. Nonresidents and Residents with Other State Income If you are domiciled in Missouri but have no permanent home here, have a permanent home elsewhere, and spend 30 days or fewer in the state, you are not treated as a resident.
Nonresidents who earn income from Missouri sources still owe tax on that income. The return is calculated as though you were a full-year resident, then reduced on Form MO-NRI to prorate the tax to your Missouri-source earnings.4Missouri Department of Revenue. Nonresidents and Residents with Other State Income FAQs Missouri residents who paid income tax to another state can claim a credit on Form MO-CR, limited to the smaller of the tax paid to the other state or the Missouri tax on that same income.
The St. Louis City Earnings Tax
The City of St. Louis imposes a 1% earnings tax on wages, salaries, commissions, and other compensation, authorized under Mo. Rev. Stat. ยง 92.110.5Justia Law. Missouri Code 92.110 – Tax May Be Levied on Earnings and Profits Two groups owe it:
- City residents pay 1% on all earnings, regardless of where the employer is located or where the work is performed.6City of St. Louis. Individual Earnings Tax Information
- Non-residents who work in the City pay 1% on the portion of their income earned within City limits.6City of St. Louis. Individual Earnings Tax Information
City Versus County
St. Louis City is an independent city and is not part of any county. If you live in Creve Coeur, Clayton, Kirkwood, or any other municipality within St. Louis County, you are not a City resident and do not owe the earnings tax on your income unless you physically work inside City limits. Plenty of people who say they live “in St. Louis” actually live in the County and have no earnings tax obligation at all. Your address and which boundary your property sits inside determine which side you’re on.
Remote and Split-Location Work
The earnings tax follows physical presence. If any portion of a day is worked within City limits, that whole day counts as a City workday.6City of St. Louis. Individual Earnings Tax Information Non-residents who split time between a City office and a home outside the City calculate their tax from the ratio of days worked inside the City to total days worked, using the non-residency deduction formula on Form E-1. If you work remotely from a home outside the City for a City-based employer, the tax generally does not apply to the days you work from home, because you are not physically present in the City on those days.
Filing the Two Returns
You file two separate returns. Each has its own form, portal, and mailing address.
Missouri State Return
The state return uses Form MO-1040, available from the Missouri Department of Revenue.7Missouri Department of Revenue. Forms and Manuals You’ll need your federal return, all W-2s, and any 1099s. Because Missouri starts with your federal adjusted gross income, finish the federal return first.3Missouri Department of Revenue. Nonresidents and Residents with Other State Income You can file electronically through the Department’s portal. Paper returns go to Jefferson City: P.O. Box 329 if you owe a balance, P.O. Box 500 for refund returns.8Missouri Department of Revenue. Missouri Department of Revenue Now Accepting E-filed State Tax Returns
City Earnings Tax Return
The City return uses Form E-1, filed with the St. Louis Collector of Revenue.9City of St. Louis. E-1 Form (Fillable) You report total gross compensation, apply the 1%, subtract any amount your employer already withheld, and pay the difference. If you paid income tax to another city or state on the same earnings, you may also need Form E-1CR.10City of St. Louis. File Individual Earnings Taxes Many employers withhold the 1% automatically, but even when they do, you are responsible for verifying the full amount was withheld and filing the return.6City of St. Louis. Individual Earnings Tax Information
Deadlines and Extensions
Both returns are due April 15.11Missouri Department of Revenue. Individual Income Tax FAQs If you file a federal extension, Missouri automatically grants a matching state extension through October 15, with no separate state extension form required.12Missouri Department of Revenue. Form MO-60 Application for Extension of Time to File An extension gives you more time to file, not more time to pay. If you expect to owe, estimate and pay by April 15 to avoid interest.
City extensions work differently. You must prepay at least 90% of your total earnings tax by April 15 to avoid penalty and interest during the extension period.10City of St. Louis. File Individual Earnings Taxes Underestimating that prepayment triggers the same penalties as filing late.
What Late Filing Costs
The consequences differ sharply between state and city.
On the Missouri return, the Department of Revenue assesses a penalty on any return not filed by the due date.13Missouri Department of Revenue. Pay Individual Income Taxes Online Interest on unpaid balances runs at 7% annually for 2026.14Missouri Department of Revenue. Statutory Interest Rates
City penalties are steeper. A late earnings tax return draws a 5% penalty of the unpaid tax for each month or partial month, capped at 25%. Interest also accrues at 1% per month, or 12% annually, until the balance is paid in full.10City of St. Louis. File Individual Earnings Taxes Five months of inattention produces the maximum 25% penalty plus 5% interest on whatever you owed.
One Related Tax to Know About
Neither the state return nor the City earnings tax covers personal property. St. Louis residents separately owe personal property tax on vehicles, boats, and other tangible personal property. You must declare your personal property by April 1 each year, and missing that deadline triggers a 10% assessment penalty. Bills are mailed in November and due by December 31, with penalty and interest accruing after January 1.15City of St. Louis. Pay Your Personal Property Tax You cannot renew your vehicle registration until all delinquent personal property taxes are paid, which is the detail that catches most people off guard.