Missouri (MO)
April 15, 2026
October 15, 2026
✓ Automatic w/ Federal
MO — MissouriMissouri Personal Income Tax Extension — What You Need to Do
If you have a federal extension (Form 4868), Missouri automatically grants you a matching extension to October 15, 2026 — no separate Missouri form needed. You only need to file Form MO-60 if you expect to owe Missouri tax, want a Missouri extension without a federal one, or need more time than the federal extension provides.
Missouri Extension Checklist — 2026
Two things to handle. Form MO-60 is only required in specific situations.
April 15, 2026
Pay Any Missouri Tax Due (File Form MO-60 If So)
Check with Form MO-60 Missouri Department of Revenue
PO Box 3400
Jefferson City, MO 65105-3400
Keep a copy of approved Form MO-60 to attach to your return.
October 15, 2026
File Federal + Missouri Return
File your federal return now and add your Missouri state return — Form MO-1040 — in the same session, attaching a copy of your approved extension. Filing sooner means a faster refund. Your Missouri extended deadline is October 15.
Start Federal + Missouri Return →
Secure eFile · Step-by-step guidance · 24/7 support
Missouri Late Filing & Payment Penalties — What It Costs to Wait
Missouri’s late-payment penalty is a flat one-time charge, unlike the monthly-accruing late-filing penalty.
| Charge Type | Rate | Cap | Trigger |
|---|---|---|---|
| Late Filing Penalty | 5% of unpaid tax per month (or part) | 25% | Return filed late without valid extension coverage |
| Late Payment Penalty | 5% of unpaid tax (one-time, flat) | N/A — flat charge | Tax unpaid after April 15, 2026 |
| Interest | 7% per year (2026) | No cap | Accrues from April 15 on any unpaid balance |
Missouri State Extension Details
| Extension Type | Automatic with Federal Extension |
| Original Filing Deadline | April 15, 2026 |
| Extended Filing Deadline | October 15, 2026 |
| Extension Period | 6 months (federal-aligned) |
| Extension Form | Form MO-60 — only required if you expect to owe tax, need an extension without a federal one, or need more time than the federal extension provides |
| Return Form | Form MO-1040 |
| Federal Extension Required? | Not required, but simplifies the process — a federal extension automatically covers Missouri if you don’t expect to owe tax |
| Payment Deadline | April 15, 2026 (extension does not extend time to pay) |
| Online Payment Portal | MyTax Missouri |
| Extension (Form MO-60) Mailing Address | Missouri Department of Revenue, PO Box 3400, Jefferson City, MO 65105-3400 |
| Return Mailing Address (refund/no tax due) | Missouri Department of Revenue, PO Box 500, Jefferson City, MO 65105-0500 |
| Return Mailing Address (payment enclosed) | Missouri Department of Revenue, PO Box 329, Jefferson City, MO 65105-0329 |
| State Agency | Missouri Department of Revenue |
| Late Filing Penalty | 5% of unpaid tax per month, up to 25% |
| Late Payment Penalty | 5% of unpaid tax, flat one-time charge |
| Interest Rate (2026) | 7% per year |
Missouri Tax Extension — Frequently Asked Questions
Do I need to file a Missouri extension form?
No, not if you already have a federal extension and don’t expect to owe Missouri tax. File Form MO-60 only if you expect to owe, want a Missouri extension without a federal one, or need more time than the federal extension gives.
Is Missouri’s late-payment penalty charged every month?
No. Unlike the late-filing penalty (5% per month, capped at 25%), the late-payment penalty is a flat 5% one-time charge on the unpaid balance.
What if I owe Missouri tax when I request the extension?
File Form MO-60 with payment by April 15, 2026. The extension covers filing only, not payment.
What if I’m due a refund?
If you’re due a refund, no extension form or payment is required. Filing sooner still gets your refund to you faster.
Which Missouri return form do I need?
Form MO-1040 is Missouri’s individual income tax return, used by residents, part-year residents, and nonresidents alike.
Where do I mail my return versus my extension payment?
Extension payments (Form MO-60) go to PO Box 3400. Completed returns go to PO Box 500 (refund/no tax due) or PO Box 329 (payment enclosed) — different addresses, so double-check before mailing.
Ready to File? Start Federal + Missouri
File your federal return and add Missouri state in the same session. October 15 extended deadline — secure, fast, with live support.