Iowa calendar and forms

Iowa runs its own calendar. The IA 1040 is due April 30, 2027, fifteen days after the federal return, and the four estimated payments fall on the last day of April, June, September and January rather than the 15th. The extension is automatic and needs no form, but it has a condition most people miss: at least 90% of the final Iowa tax must be paid by April 30, through withholding, estimates or a payment with the IA 1040V. Meet the 90% and you have until November 1, 2027 to file with no penalty, only interest at 9% a year on what is left. Miss it and there is no extension at all. A federal Form 4868 does nothing for Iowa.

The form side is short. There is one return for everyone, the IA 1040, and a Schedule 1 that carries the Iowa modifications: Social Security, retirement income, military pay, the 529 deduction. Most Iowans touch those two pages and nothing else. The rest of the list below is for people who moved or work across the state line, who owe estimated tax, or who need to fix a return already filed.

The 2027 filing season, dated

How the extension really works

Iowa Administrative Code 701-301.2 puts it this way: a taxpayer who “has paid at least 90 percent of the tax required to be shown due by the due date and has not filed a return by the due date” is treated as having asked for an extension, and the Department “will automatically grant an extension of up to six months to file the return.” No application, no form. Withholding, estimated payments and a payment sent with the IA 1040V by April 30 all count toward the 90%, which is figured against the tax finally shown on the return, so a guess that comes in a little high is safer than one that comes in a little low. When the 90% test is met there is no late-filing penalty; interest at 9% a year still runs on the unpaid 10% from April 30.

Two things catch people. First, the federal extension is not an Iowa extension; the only exception is a taxpayer with a tax home abroad whose federal extension runs past six months, who gets the same extra time with proof attached. Second, the extension is to file, not to pay. Someone who expects to owe $2,000 with nothing withheld has no extension until $1,800 is in the Department’s hands, by a payment on EasyPay Iowa or a check with the IA 1040V. Below 90%, a 5% late-filing penalty and a 5% late-payment penalty apply along with the interest.

Estimated payments

For 2026, estimated payments are required when the Iowa tax expected on income that has no Iowa withholding is $1,000 or more. That is the new threshold; it was $200 through 2025. The due dates are Iowa’s own, the last day of the month: April 30, June 30 and September 30, 2026 and January 31, 2027 for the 2026 year, with the January date sliding to February 1 because the 31st is a Sunday. A requirement that arises later in the year starts with the next date and fewer installments. The safe harbor follows the federal pattern, 90% of this year’s tax or 100% of last year’s, paid on time, with no 110% tier for higher incomes (verify the 2026 IA 2210 wording); the penalty is figured on IA 2210, or IA 2210 Schedule AI for income that arrived unevenly. Farmers and commercial fishers with two-thirds of their income from farming or fishing pay once by January 15 or file and pay by March 1 with IA 2210F.

Because Iowa exempts Social Security at any age and retirement income from 55, retirees are rarely the ones caught. The people who are: the self-employed, pass-through owners, landlords, anyone with a large capital gain, and a worker under 55 who took an IRA distribution with no Iowa withholding.

The forms, in the order a filer meets them

Filing free, paying, and checking a refund

Iowa has no state-built filing program and was never part of IRS Direct File, which ended after the 2025 season. The Department posts a page of free e-file vendors under the IRS Free File program, each with its own income cap: for 2025 returns the offers ran from $32,000 of AGI (1040NOW, any Iowan) to $89,000 (1040.com, TaxAct, TaxSlayer, two with age limits), with military offers at $89,000 across the board; the 2026-season offers are posted when the season opens (verify). VITA and AARP Tax-Aide sites prepare the Iowa return with the federal one at no charge for those who qualify. Over 92% of Iowa returns were filed electronically last season.

Payments go through EasyPay Iowa, where you pick the tax type and year; letters, account history and payment plans are in a GovConnectIowa account. Refund status is on Where’s My Refund, which asks for the Social Security number, the tax year and the exact refund amount. The Department’s stated window is 30 days for an e-filed return; paper takes longer. Some refunds are held while the Department sends a letter to confirm you filed. The letter is real; a text about an Iowa refund is not.

Paper returns go to Iowa Income Tax Document Processing, PO Box 9187, Des Moines IA 50306-9187 (verify). The Department’s office is in the Hoover State Office Building, 1305 E. Walnut St., Des Moines, open 8:00 to 4:30 Central, Monday through Friday. Taxpayer questions: 515-281-3114 or 800-367-3388. Billings and collections: 866-339-7912.