How to pay Iowa estimated taxes.

Iowa collects its own estimated tax through the Iowa Department of Revenue, separate from the IRS. Here’s who needs to pay, when, and how to pay online.

Do you need to pay?

You must make estimated payments if you expect to owe $1,000 or more in Iowa tax on income not subject to withholding. This is up from $200 for tax years before 2026.

Iowa follows the federal method: pay at least 90% of this year's tax or 100% of last year's tax. If last year's federal AGI (plus Iowa bonus depreciation/section 179 and other decoupling adjustments) was over $150,000 ($75,000 married filing separately), the prior year amount is 110%.

If you underpay: Figured on Form IA 2210 as a daily interest charge; the 2026 rate is 10% a year (0.027397% per day).

For how to pick a safe amount, see how much to pay in estimated taxes.

Deadlines

Four equal installments due April 30, 2026, June 30, 2026, September 30, 2026, and January 31, 2027. Because January 31, 2027 is a Sunday, the fourth payment is due Monday, February 1, 2027. This does not match the federal schedule: each Iowa date is later in the month.

A date on a weekend or holiday moves to the next business day. Pay at least two business days early.

Paying Iowa, step by step

What you need

Nothing to set up. GovConnectIowa takes payments without an account.
Your Social Security number and a copy of last year's Iowa return.
Your bank routing and account numbers.

Start at GovConnectIowa, Iowa's official payment site.

Go to GovConnectIowa and click Make a Payment on the homepage. You don't need a logon.
Choose the individual income estimated tax payment option.
Enter your SSN, the tax period (the year end, such as 12/31/2026, not the installment date), and the amount.
Pay from your bank account or by credit/debit card (card fee applies).
Submit by 11:59 p.m. Central on the due date and save the confirmation.

Other ways to pay: Mail the IA 1040ES voucher with a check or money order, or pay in person. Card payments carry a fee charged by the payment provider. Individual income tax can't be paid by ACH credit.

Iowa will not fill these payments in for you. Your preparer has to enter each estimated payment on your Iowa return. Keep your own record of the date, amount, and confirmation number.

Extension payments

Iowa has no extension form, and a federal extension does not apply. If at least 90% of your tax is paid by April 30, you automatically have until October 31 to file. It does not extend the time to pay: interest runs on any balance after April 30. To pay, use GovConnectIowa or the IA 1040V voucher.

Make this year's first estimated payment as a separate transaction, marked as an estimate for the current year.

Good to know

Iowa due dates fall on the last day of the month (April 30, June 30, September 30, January 31), not the 15th. When that day is a weekend or holiday, the due date moves to the next business day, so the final 2026 payment is due February 1, 2027.
First-time payments through GovConnectIowa are verified with your bank, which can take up to 5 business days to post.
Paying without a logon means you can't see your payment history; a GovConnectIowa logon lets you check your estimates before you file.
Nonresident owners of a pass-through entity that elects PTET, or that includes them on a composite return, don't make estimates on that income.
Moved this year? You may owe estimates to both Iowa and your other state for the part of the year you lived or earned income in each.
Paying the IRS too? Follow the federal walkthrough. Other states each have a guide of their own.

Official sources

Checked October 2026 against the Iowa Department of Revenue's own publications.

This guide is for general education and reflects rules as of October 2026. Tax law and agency websites change, and your situation may have details that change the answer. Please talk with your tax professional before acting on it.