Enterprise
Individual & Small Business
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Federal 2026 estimated tax due dates, for comparison: April 15, 2026, June 15, 2026, September 15, 2026, January 15, 2027.
Who must pay Iowa estimated tax?
Every individual or married couple filing a joint Iowa return that expects to have a tax liability of $1,000 or more from income not subject to withholding. (Threshold was $200 before tax years beginning on or after January 1, 2026.)
How do you avoid a Iowa underpayment penalty?
Pay 100% of the prior year's Iowa tax liability (12-month year), or 110% if the prior year's federal AGI (plus Iowa bonus depreciation/section 179 and other decoupling adjustments) exceeded $150,000 ($75,000 MFS); or pay at least 90% of the tax on current-year annualized income (Form IA 2210). Farmers/fishers (2/3 of gross income): one payment by January 15, 2027 and file by April 30, or file and pay in full by March 1, 2027.
Are there local estimated payments?
Iowa school district surtax (and any emergency medical services surtax) is computed on the state IA 1040 and paid with state tax; there are no separate local estimated payments.
How much should you pay?
Start with your federal estimate: the free Quarterly Estimated Tax Calculator works out your 2026 federal payments and safe harbor. Iowa figures its own tax, so the state amount is separate.