To file your Indiana state taxes, full-year residents complete Form IT-40, part-year residents and nonresidents use Form IT-40PNR, and both can be submitted electronically through the state’s INTIME portal, through certified tax software, or on paper by mail. Your 2025 return and any tax owed are due April 15, 2026.1Indiana Department of Revenue. Tax Season 2025 Has Arrived
Who Has to File
If you were a full-year Indiana resident and your gross income was more than your total exemptions, you need to file a return. The quick test: add $1,000 for yourself, $1,000 for a spouse on a joint return, and $1,000 for each dependent. If your income tops that figure, file.2Indiana Department of Revenue. Who Should File a Tax Return
Part-year residents and nonresidents who earned Indiana income also file, but on Form IT-40PNR rather than the standard IT-40.3Indiana Department of Revenue. IT-40PNR Part Year and Full Year Nonresident Individual Income Tax Booklet
One boundary worth knowing: Indiana has reciprocal agreements with Illinois, Kentucky, Michigan, Ohio, Pennsylvania, and Wisconsin. Wages earned in Indiana by a resident of one of those states are not subject to Indiana income tax on those wages. If that’s you, submit a residency affidavit to your Indiana employer so they don’t withhold Indiana tax from your paychecks.4Legal Information Institute. 45 IAC 3.1-1-115 Reciprocal Agreement States
What to Gather Before You Start
Pull these together first so you aren’t hunting through drawers mid-return:
- Social Security numbers for you, your spouse if filing jointly, and every dependent
- Your completed federal Form 1040, because your federal adjusted gross income is the starting line for the Indiana return
- W-2 forms from every employer, showing wages and Indiana withholding
- 1099 forms for interest, dividends, freelance work, retirement distributions, or other non-wage income
- Records of deductible expenses: rent receipts, property tax statements, 529 plan contribution records
Then pick the right form. Full-year residents use IT-40. Part-year and nonresidents use IT-40PNR. Both are available on the Indiana Department of Revenue website.3Indiana Department of Revenue. IT-40PNR Part Year and Full Year Nonresident Individual Income Tax Booklet
Three Ways to Submit Your Return
INTIME (The State Portal)
The Indiana Tax Information Management Engine, known as INTIME, is the Department of Revenue’s online filing and payment system. You set up an account, choose the tax year, and enter your return directly. Submission generates a confirmation number.5Indiana Department of Revenue. INTIME
Third-Party Tax Software
Certified programs such as TurboTax, H&R Block, and FreeTaxUSA will prepare and transmit your Indiana return. They step you through each schedule, flag common errors, and send a digital receipt within minutes once the state accepts the filing.
By Mail
Paper filers need the right P.O. box, because Indiana splits incoming mail by whether a payment is enclosed:
- Refund or no payment enclosed: Indiana Department of Revenue, P.O. Box 40, Indianapolis, IN 46206-0040
- Payment enclosed: Indiana Department of Revenue, P.O. Box 7224, Indianapolis, IN 46207-7224
Include Form IT-40V (the payment voucher) with any check. Paper returns take substantially longer to process than electronic ones.6Indiana Department of Revenue. Mail in Tax Forms
How Your Indiana Tax Is Calculated
The Indiana return starts with the federal adjusted gross income from your Form 1040, then applies state-specific additions and subtractions. Some income is added back, such as interest from out-of-state municipal bonds. Other items come out. Indiana does not tax Social Security benefits, so any Social Security included in your federal AGI gets subtracted on the state return.7Indiana Department of Revenue. Deductions
Deductions
A few deductions commonly reduce taxable income:
- Renters can deduct up to $3,000 of rent paid on a primary residence during the year, or $1,500 if married filing separately.8Indiana General Assembly. Indiana Code 6-3-2-6 Deduction Rent Payments
- Homeowners can deduct up to $2,500 of property taxes paid on their primary Indiana residence, or $1,250 if married filing separately.
Exemptions
Indiana allows a $1,000 exemption for yourself, $1,000 for a spouse on a joint return, and $1,000 for each dependent. Qualifying dependent children get an additional $1,500 exemption on top of that, which doubles to $3,000 the first year you claim the child.9Indiana Department of Revenue. Schedule 3 Exemptions
The Flat State Rate and a County Rate on Top
After deductions and exemptions, the state tax is a flat 3.00% of what remains for tax year 2025.10Indiana Department of Revenue. Rates Fees and Penalties
Every Indiana county also imposes its own income tax, running from 0.5% to 3.0% depending on where you lived on January 1 of the tax year. Full-year residents calculate the county piece on Schedule CT-40 by multiplying taxable income by the applicable county rate, then add that result to the state tax on the IT-40. The rate chart for all 92 counties is printed on the back of Schedule CT-40 and posted on the Department of Revenue website.11Indiana Department of Revenue. Schedule CT-40 County Tax Schedule for Full-Year Indiana Residents
Credits
Credits come off the tax itself rather than reducing taxable income, which makes them more valuable dollar-for-dollar than a deduction of the same size. Two to know:
- The CollegeChoice 529 credit equals 20% of your contributions to an Indiana CollegeChoice 529 savings plan, capped at $1,500 per year, or $750 if married filing separately. A $7,500 contribution reaches the full $1,500 credit.12Indiana Department of Revenue. Income Tax Information Bulletin 98 Indiana 529 Savings Plan Credit
- The Unified Tax Credit for the Elderly runs from $40 to $140 if you or your spouse were 65 or older during the tax year and your household federal AGI was under $10,000. The exact amount depends on income and whether both spouses are 65 or older.13Indiana General Assembly. Indiana Code 6-3-3-9 Unified Tax Credit for the Elderly
Paying What You Owe, or Getting a Refund
Add state tax, county tax, and subtract credits. Compare that total to the Indiana tax already withheld from your paychecks plus any payments you’ve made. If withholding was more than the bill, you’re due a refund. If it was less, pay the difference by April 15.
INTIME accepts payment by bank account at no charge, or by debit or credit card for a processing fee.14Indiana Department of Revenue. Payments and Billing
Electronically filed returns usually process within three weeks; paper returns can take up to twelve. You can check status on INTIME or by calling the Department of Revenue at 317-232-2240 (option 3). You’ll need your Social Security number and the whole-dollar amount of the refund you’re expecting.15Indiana Department of Revenue. Where’s My Refund
If You Need More Time
You can get an automatic extension by filing Form IT-9 on or before April 15, or by obtaining a federal extension. That pushes your filing deadline to November 16, 2026, but it does not push the payment deadline. Any tax unpaid after April 15 accrues interest. To avoid a late-payment penalty on top of that interest, pay at least 90% of what you expect to owe by April 15 and the remainder by November 16.16Indiana Department of Revenue. Extension of Time to File
What Late Filing or Underpayment Costs
If you file late or come up short on April 15, Indiana charges a penalty of 10% of the unpaid tax. Interest also accrues on the balance; for calendar year 2026, the rate is 7% per year.17Indiana Department of Revenue. Departmental Notice 03
Fixing a Return After You File
If you find an error after filing, such as unreported income or a deduction you missed, you have three years from the original due date or the date the tax was paid, whichever is later, to amend. For tax years 2021 forward, you amend by choosing the “Amended” option on Form IT-40 instead of using a separate amendment form. If your federal return also changed, file Form 1040X with the IRS first, then amend the Indiana return to match.18Indiana Department of Revenue. Amend A Return
Simple math errors don’t need an amended return; the Department of Revenue corrects those during processing. If you forgot to attach a W-2 but aren’t reporting more income, wait for the department to contact you rather than refiling.