Missouri tax deadlines 2026
Last updated May 14, 2026
- Missouri: Progressive individual income tax 0%-4.7% (top bracket at $8,968+, scheduled to reduce to 4.5% subject to revenue triggers). Kansas City + St. Louis levy local earnings tax (1%).
- Missouri offers a Pass-Through Entity Tax (PTET) election — federal SALT cap workaround.
- Kansas City and St. Louis each levy a 1% earnings tax on residents and non-residents working in those cities. Annual returns and quarterly withholdings required separately from state.
Missouri individual income tax
Filing deadline
April 15, 2027
Extension deadline
October 15, 2027
Missouri conforms to the federal April 15 individual income tax deadline. Progressive individual income tax 0%-4.7% (top bracket at $8,968+, scheduled to reduce to 4.5% subject to revenue triggers). Kansas City + St. Louis levy local earnings tax (1%).
Quarterly payments
Q1 2026
Jan 1 – Mar 31, 2026
Q2 2026
Apr 1 – May 31, 2026
Q3 2026
Jun 1 – Aug 31, 2026
Q4 2026
Sep 1 – Dec 31, 2026
Missouri Pass-Through Entity Tax (PTET)
Missouri SALT Parity Act allows pass-through entity election (Form MO-1041). Owners receive Missouri state tax credit for entity-paid PTE tax.
Authoritative sourceFederal individual income tax (Form 1040)
Filing deadline
April 15, 2027
Extension deadline
October 15, 2027
Quarterly payments
Q1 2026
Jan 1 – Mar 31, 2026
Q2 2026
Apr 1 – May 31, 2026
Q3 2026
Jun 1 – Aug 31, 2026
Q4 2026
Sep 1 – Dec 31, 2026
Penalty summary
Failure-to-file: 5%/month up to 25%. Failure-to-pay: 0.5%/month. Interest accrues on unpaid balances.
Federal S-corp & partnership (Form 1120-S / 1065)
Filing deadline
March 16, 2027
Extension deadline
September 15, 2027
Federal C-corporation (Form 1120, calendar year)
Filing deadline
April 15, 2027
Extension deadline
October 15, 2027
Federal payroll (Form 941)
Quarterly payments
Q1 941
Jan – Mar 2026 wages
Q2 941
Apr – Jun 2026 wages
Q3 941
Jul – Sep 2026 wages
Q4 941
Oct – Dec 2026 wages
File these Missouri returns with confidence
TaxScout's tax form library walks through every IRS form CPA firms file for Missouri clients — who must file, key fields, common mistakes, and step-by-step instructions.
Frequently Asked Questions
Missouri-specific and federal questions for tax year 2026.
If you owe tax and file after April 15 without an approved extension, the IRS assesses a failure-to-file penalty (5% of unpaid tax per month, up to 25%) plus a failure-to-pay penalty (0.5% per month) plus interest. If you're due a refund, there's no late-filing penalty — but you have only three years from the original deadline to claim it. CPAs should advise extension filers that an extension extends time to file, never time to pay.
Multi-state filing without the spreadsheet
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