Indiana calendar and forms

Indiana’s calendar runs on the federal dates with one exception. The IT-40 is due April 15, 2027, the same day as the Form 1040; the four estimated payments fall on the federal dates; but the extension runs to November 15, 2027, a month past the federal October date. A federal extension carries over to Indiana automatically; without one, file Form IT-9 by April 15. Either way the extension covers the paperwork only. At least 90% of the tax must be paid by April 15 to avoid the late-payment penalty, and interest runs from April 15 on whatever is unpaid. The form side is a single return, the IT-40, with numbered schedules that attach only when they apply, and one schedule nearly everyone files: CT-40, the county tax.

Most Indiana filers touch four pages: the IT-40, Schedule CT-40 for the county rate, Schedule 3 for the exemptions, and Schedule 2 if they rent, own a home, draw Social Security or served in the military. The rest of the list below is for people who moved, who 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 works

If you filed a federal Form 4868, Indiana honors it; check the extension box on the IT-40 when you file. If not, Form IT-9 by April 15, 2027, on paper or through INTIME, does the same thing for Indiana alone. Both extend the time to file, to November 15, 2027. Neither extends the time to pay. The late-payment penalty is 10% of the unpaid tax, or $5 if more. The Department waives it if at least 90% of the final state and county tax was paid by April 15 and the balance is paid with the return by the extended date. Interest runs on anything paid after April 15 regardless. Active-duty military outside the United States get an automatic 60 days; a combat zone gives 180 days after leaving it.

Estimated payments

Indiana expects estimated payments when the state and county tax for the year, after withholding and credits, will be more than $1,000. One ES-40 or one INTIME payment covers both taxes. The penalty is figured on Schedule IT-2210, and there is none if payments and withholding reach 90% of this year’s tax or 100% of last year’s in four equal, timely installments; 110% of last year’s if last year’s federal AGI was over $150,000 ($75,000 married filing separately). The penalty has been 10% of each period’s shortfall; from July 1, 2026 it is figured at the Department’s statutory interest rate. Because Indiana taxes pensions and IRA withdrawals in full, retirees are the people most often caught: an out-of-state IRA custodian withholds nothing for Indiana, and a Roth conversion withholds nothing for anyone. The fix is an ES-40.

The forms, in the order a filer meets them

Filing, paying and checking a refund

Almost every Indiana return is filed electronically with the federal return. The Department’s 2025 booklet put an e-filed refund at 10 to 14 business days on average and a paper refund at up to 12 weeks, and asks filers to wait three to four weeks before calling. Paid preparers who file more than 10 individual returns must e-file unless the client signs Schedule IN-OPT. Early in the season the Department sends identity-confirmation letters to a share of filers; a return that draws one waits until the letter is answered.

INfreefile is Indiana’s free-filing program: four commercial vendors (TaxSlayer, FreeTaxUSA, OLT and 1040.com for the 2025 season) file the federal and Indiana returns free under an income limit, $51,000 of AGI at FreeTaxUSA and OLT, up to $89,000 at TaxSlayer and 1040.com with floors and an age limit, more for active-duty military and EITC filers. The 2026-season limits are to come. Go in through the Department’s INfreefile page, not the vendor’s front door, or the Indiana return may not be free. Indiana has not taken part in IRS Direct File.

INTIME, at intime.dor.in.gov, is the Department’s online account. Without an account it makes a payment, checks a refund, requests an extension and answers a letter. With one it shows every estimated payment and every notice, lets you choose electronic-only correspondence under the 2026 law, and sets up a payment plan. A bank-debit payment costs nothing; card payments go through a processor that charges a fee. The Department’s individual FAQ page covers the account.

Where’s my refund is the refund status tool on INTIME; you need your Social Security number and the exact refund amount. For a person, the Department’s individual income tax line is 317-232-2240, Monday through Friday, 8 a.m. to 4:30 p.m. Eastern, for payments, billing, refunds and general questions. There are ten district offices around the state for in-person help, by appointment through the Department’s contact page.