Indiana Form ES-40 is the one-page voucher you send to the Indiana Department of Revenue with each quarterly estimated state income tax payment. You use it when you expect to owe at least $1,000 in Indiana tax after withholding and credits, and you can submit it either electronically through INTIME or on paper with a check. The form itself is short. Getting the amount right and hitting each quarterly deadline is what actually matters.
Who Needs to File It
You need to make estimated payments if you expect to owe at least $1,000 in Indiana income tax for the year after subtracting withholding and credits. That threshold catches most self-employed workers, sole proprietors, partners, S-corporation shareholders, and anyone with untaxed income of any real size. If your employer withholds Indiana tax from every paycheck and that covers your full liability, you can skip the form.
Situations that typically trigger estimated payments:
- Self-employment or freelance income with no employer withholding.
- Rental income, dividends, or capital gains that arrive without Indiana tax taken out.
- Pension or IRA distributions with no state withholding, or not enough.
- A main job that withholds Indiana tax and a side income source that doesn’t.
Indiana also has county income taxes, and your estimated payment needs to cover both the state and the county portion. The applicable county rate is based on where you lived on January 1 of the tax year.
Quarterly Due Dates
Indiana uses the same quarterly schedule as the IRS. For the 2026 tax year:
- First quarter: April 15, 2026
- Second quarter: June 15, 2026
- Third quarter: September 15, 2026
- Fourth quarter: January 15, 2027
If a due date falls on a weekend or state holiday, the deadline shifts to the next business day. Mailed payments count by postmark date. Electronic payments must be submitted by 11:59 p.m. ET on the due date.
Filling Out the Voucher
Form ES-40 is a payment voucher, not a return. You can download it from the DOR’s individual tax forms page or complete it inside the DOR’s online portal.1Indiana Department of Revenue. Current Year Individual Tax Forms The fields are straightforward:
- Your name and Social Security number. If you file jointly, include both names and both SSNs. The primary taxpayer’s SSN should match the one on your annual IT-40.
- Your current mailing address, matching what the DOR has on file so the payment lands in the right account.
- Your county code, a two-digit number for your Indiana county of residence as of January 1. The code list is in the form instructions and on the DOR website.
- The filing period, marking which quarter this payment covers.
- The payment amount. Write the same amount on your check or money order.
Check the SSN and county code carefully. A wrong SSN can leave your payment sitting unmatched to your account, and the wrong county code misallocates the county portion.
How to Submit It
There are two ways to get the payment in.
Online through INTIME. Indiana’s Taxpayer Information Management Engine at intime.dor.in.gov accepts estimated payments by bank transfer (ACH debit) or credit card. If you pay online, you don’t need to mail the paper voucher; the system records the payment and gives you an immediate confirmation.2Indiana Department of Revenue. Estimated Payments
By mail. Print or tear out the ES-40, write a check or money order payable to the Indiana Department of Revenue, and mail both to the address printed on the form. Don’t staple or paper-clip the check to the voucher. Write your SSN and the tax period on the memo line so the DOR can reunite them if they get separated.
If you’re mailing close to a deadline, a certificate of mailing from the post office gives you a dated record. The postmark is what counts, but proof is worth having if a penalty question comes up later.
Calculating the Amount
Start with your expected adjusted gross income for the year. Indiana applies a flat state rate of 2.95 percent for the 2026 tax year, with certain Indiana-specific modifications, then adds your county rate on top. The DOR’s county tax rate table lists each county’s rate.
Once you have total expected liability (state plus county), subtract any Indiana withholding your employers will send in and any credits you expect to claim. What’s left is what you owe through estimated payments. Divide by four for equal installments, or allocate more to quarters when income actually arrives.
There’s a safe harbor: if your estimated payments plus withholding equal at least 100 percent of your prior year’s Indiana tax, you generally avoid the underpayment penalty even if you end up owing more when you file. That’s a useful fallback if your income jumps unexpectedly.
Underpayment Penalty
Indiana charges a penalty when withholding plus estimated payments don’t cover enough of your liability. It’s calculated quarter by quarter on the underpaid amount, using an interest rate the DOR sets each year. It compounds based on how much you underpaid and how long the shortfall lasted.2Indiana Department of Revenue. Estimated Payments
You avoid the penalty entirely if any of these apply:
- Your total tax due after withholding and credits is less than $1,000.
- Estimated payments plus withholding cover at least 100 percent of your prior year’s Indiana tax.
- You paid at least 90 percent of your current year’s actual liability through withholding and timely estimated payments.
When you file your IT-40, Schedule IT-2210 is where the penalty calculation lives, including the annualized income method if your income was uneven across the year.
Changing Payments Mid-Year
Your first-quarter estimate doesn’t lock you in. If income runs higher than expected, raise the next quarter’s payment. If it drops, lower it. Each voucher is independent, so you fill in whatever the current projection supports.
One thing to know: piling a whole year’s shortfall into the January fourth-quarter payment closes the fourth-quarter gap but doesn’t undo penalties for earlier quarters where you were underpaid. Adjust as soon as you see the estimate is off. Nothing stops you from paying early or sending extra payments between the official due dates.