State filing information
Iowa
Business tax filing in Iowa: state returns, sales tax, other business taxes, and the federal dates that apply everywhere.
- Iowa corporate income tax returns for calendar-year filers are due April 30.
- Iowa partnership returns are due April 30.
- Iowa sales and use tax returns are due on the Last day of the following month.
- Other business taxes in Iowa: Franchise tax (IA 1120F).
- The next federal deadline that applies in Iowa is Q3 2026 estimated tax payment (Form 1040-ES) on .
Corporate income tax return
Partnership / S corporation returns
Sales tax return
Other business taxes
Other business taxes
| Tax | Who owes it | Due |
|---|---|---|
| Franchise tax (IA 1120F) | Financial institutions (banks, savings and loan associations, etc.) instead of corporation income tax | – |
Rules in full
Corporate income tax
Iowa corporation income tax return (IA 1120) is due on the last day of the fourth month after the end of the tax year (cooperatives: 15th day of the ninth month).
Extension. Automatic six-month extension to file (no form required) for taxpayers who have paid 90% or more of the correct tax by the original due date;...
Partnerships and S corporations
S corporations (and partnerships) may make a Pass-Through Entity Tax (PTET) election to be taxed at the entity level; electing entities must make estimated payments; the PTET election must be made by the date six months after the original due date of the return (2025 IA 1120S instructions). Composite return (IA PTE-C) requirements apply to nonresident owners.
Sales and use tax
Due date. Monthly returns and payments are due on or before the last day of the month following the end of the month in which the tax was collected; annual returns are due on or before January 31 for the prior calendar year.
Filing frequency. Effective July 1, 2022, quarterly filing was eliminated: taxpayers collecting less than $1,200 in sales and use tax per year file annually; taxpayers collecting $1,200 or more per year file monthly. Deposit payments are no longer required.
Thresholds. Annual < $1,200 tax per year; monthly >= $1,200 per year.
Prepayments. None. Mandatory semimonthly deposits were eliminated effective July 1, 2022; payment is due only when a return is filed.
Notes
Iowa has no franchise, net worth, or gross receipts tax on general businesses and no LLC fee at the Department of Revenue. Iowa returns use the last day of the 4th month (April 30), not the 15th.
Federal dates that apply in Iowa
- SEP15TueIndividuals & Sole ProprietorsQ3 2026 estimated tax payment (Form 1040-ES)
- SEP15TuePartnershipsForm 1065 extended return (Form 7004), tax year 2025
- SEP15TueS-CorporationsForm 1120-S extended return (Form 7004), tax year 2025
- SEP15TueC-CorporationsQ3 2026 corporate estimated tax (Form 1120-W)
- OCT15ThuIndividuals & Sole ProprietorsForm 1040 extended return (Form 4868), tax year 2025
- OCT15ThuC-CorporationsForm 1120 extended return (Form 7004), tax year 2025
Sources
- https://revenue.iowa.gov/ official
- https://revenue.iowa.gov/taxes/file-my-taxes/business-taxes/filing-frequency-return-due-dates official
- https://revenue.iowa.gov/media/4083/download?inline= official
- https://revenue.iowa.gov/media/4373/download?inline= official
- https://revenue.iowa.gov/taxes/tax-guidance/sales-use-excise-tax/sales-and-use-tax-permit-return-filing-and-payment-changes official
- https://www.law.cornell.edu/regulations/iowa/Iowa-Code-r-701-202.1
- https://www.avalara.com/taxrates/en/state-rates/iowa/iowa-sales-tax-guide.html
Checked 2026-09-01; researcher confidence 0.85. Corrections with a link to the state's own page: contact@businesstaxdeadlines.com.