Property Tax Assessment Appeals in Lake County, Indiana and Porter County

What you are appealing

An appeal is about the assessed value, not the tax rate. Indiana assesses real property at market value in use, and distress sales like tax sales, foreclosures, and short sales usually don’t show market value (Lake County Assessor FAQ). Properties are reassessed on a four year cycle, with one fourth of the county physically reviewed each year. The Indiana Department of Local Government Finance oversees the process statewide.

Your tax bill also depends on local rates, referendums, deductions, and tax caps (Porter County Assessor FAQ). If the value is right but the bill still looks off, check that your deductions are on. Our homestead deduction page covers the big one.

Know your notice and your deadline

Form 130 sets two deadlines for a current year real property appeal. If the Form 11 notice of assessment is mailed before May 1, file by June 15 of that year. If it is mailed on or after May 1, file by June 15 of the year the tax statements are mailed (Form 130, State Form 53958).

Here is where the two counties differ. Lake County does not currently issue Form 11s, so the tax bill is your notice of assessment, and the assessor says a completed, signed Form 130 must be in by the June 15 deadline (Lake County Assessor). Porter County does mail them. For the January 1, 2026 assessment, Porter County mailed Form 11s on April 28, 2026, and the filing deadline was June 15, 2026 (Porter County Assessor).

File Form 130

File one Form 130 for each parcel you want reviewed (state appeal flowchart). Filing starts a review and requires the assessing official to schedule an informal meeting with you. Form 130 is plain about the risk: the assessment may go down, stay the same, or go up.

In Lake County, the assessor takes a signed Form 130 in person at its office, by mail, by email, by fax, or through its online appeals portal, and it encourages residential owners to use the portal (Lake County Assessor appeal filing). In Porter County, look up your parcel on the assessor’s site and open the Forms tab for a Form 130 already filled in with your parcel information. You can mail it, bring it to the office, or submit it on the site (Porter County Assessor appeal steps).

Bring evidence of value

You don’t have to attach evidence when you file, but you do have to share it at the informal meeting. The state lists an appraisal, construction costs, and sales of your property or comparable properties as examples (Form 130 instructions).

For the January 1, 2026 assessment, Porter County listed these types of evidence (Porter County Assessor):

• A 2025 sale of the property, or offers to purchase it.
• A market value in use appraisal dated January 1, 2026 from a licensed appraiser.
• Arm’s length sales of comparable properties from January 1 to December 31, 2025.
• For one to four rental units, a current lease or 12 months of rent records.
• Current dated photos of condition and estimates for repairs.

Bought the house in 2025? Porter County lists that sale as evidence for the 2026 assessment. Recent sales near you help too, and pulling those is part of our job, so call the shop and ask.

If the informal meeting doesn’t settle it

Your appeal goes to the county Property Tax Assessment Board of Appeals (PTABOA). According to the state flowchart, the board must hold a hearing within 180 days of filing and give you at least 30 days of notice. You can ask in writing, at least 20 days ahead, for the board to decide without a hearing. A $50 penalty may be charged for an unexcused failure to appear (state appeal flowchart).

If the assessment went up by more than 5 percent over the prior year’s final value, the assessor has the burden of proving it is correct. If you disagree with the board, file Form 131 with the Indiana Board of Tax Review within 45 days of the order. After that board’s final decision, you have 45 days to petition the Indiana Tax Court (state appeal flowchart).

Fixing a plain error on your record

Some problems are facts, not opinions, like a garage on the property record card that doesn’t exist, a clerical or math mistake, or a missing deduction or credit. Both county assessors say these objective appeals go on page 2 of Form 130 and can reach back up to three years of assessments. A refund also takes a Claim for Refund, Form 17T (Lake County Assessor, Porter County Assessor).

Buying or selling with taxes in mind

Real Estate USA walks through property taxes when you buy a home in Northwest Indiana and how Northwest Indiana property taxes work in general. Our property taxes Ask page answers the short version, and our buyer closing costs page covers how taxes show up at closing.

Towns we work

We help owners and buyers across Lake County and Porter County, including Crown Point, Cedar Lake, Lowell, Hebron, St. John, Hobart, Valparaiso, and Chesterton. If your assessment jumped and you want a second look at recent sales on your street, call us.

Before you file

• Find your notice. In Lake County that is your tax bill. In Porter County it is the Form 11.
• Mark June 15 and confirm the deadline for your notice.
• Pull your property record card and check the details.
• Gather sales, an appraisal, photos, or repair estimates as of January 1.
• File one Form 130 for each parcel and keep a dated copy.
• Make sure your homestead deduction is on file.

Our selling guide and buying guide cover the rest of the path. Search homes on Realest.com.

Questions owners ask

What is the deadline to appeal a property tax assessment in Indiana?

It depends on when the Form 11 notice of assessment was mailed. If it was mailed before May 1 of the assessment year, the deadline is June 15 of that year. If it was mailed on or after May 1, the deadline is June 15 of the year the tax statements are mailed. Appeals that fix certain specific errors can be filed up to three years after the taxes were first due.

Does Lake County, Indiana send a Form 11 assessment notice?

No. The Lake County Assessor says it does not currently issue Form 11s, and tax bills serve as the notice of assessment to all taxpayers. Porter County does mail Form 11s. For the January 1, 2026 assessment, Porter County mailed them April 28, 2026, with a June 15, 2026 filing deadline.

Do I need an appraisal to appeal my assessment?

No. The state appeal flowchart says no appraisal is required by the taxpayer at the county board hearing or at the Indiana Board of Tax Review. Evidence still matters. The state lists an appraisal, construction costs, and sales of the property or comparable properties as examples.

Can my assessment go up if I appeal?

Yes. Form 130 says that as a result of filing the petition, the assessment may increase, may decrease, or may stay the same.

What happens if the county board denies my appeal?

You can take it to the Indiana Board of Tax Review by filing Form 131 within 45 days of the county board order. After a final decision from that board, you can petition the Indiana Tax Court within 45 days.

Sources

• Form 130, Taxpayer’s Notice to Initiate an Appeal (State Form 53958), Indiana DLGF
• Procedure for appeal of assessment flowchart, Indiana DLGF
• Lake County Assessor resources, appeals, and FAQ
• Porter County Assessor resources, appeals, and FAQ
• Indiana Board of Tax Review forms
• Assessments, Indiana DLGF