Naperville Property Taxes: DuPage vs Will County by Tax Code

Here are four of the tax rates on Naperville's 2025 tax bills, payable in 2026. In DuPage County, Naperville Township's tax code 7025 came in at 5.8307 per $100 of equalized assessed value, and Lisle Township's code 8043 came in at 5.8361. In Will County, Wheatland Township's code 0711 totaled 6.2347, and code 0714 totaled 5.9598.

All four are Naperville. The gap between the two Will County codes is bigger than the gap between Will's lower code and DuPage's. If you're comparing homes across Naperville, the county name on the listing tells you less about the tax bill than the four-digit tax code attached to the parcel.

The one place the county line clearly decides something this fall is the calendar.

Eight days left on one side, none on the other

DuPage County mailed Naperville Township assessment notices on September 10, 2026, and published them in the Naperville Sun the next day. The deadline to file with the Board of Review is October 13, 2026, eight days from today. You can check the township rows yourself on the county's assessment status page.

On the Will County side, Wheatland Township's 2026 Board of Review window ran from August 12 through September 14, 2026, according to the Will County appeal portal. The portal no longer accepts 2026 complaints.

Lisle Township is the odd one out. As of today, DuPage's status table shows no 2026 factor, notice date or filing deadline for Lisle.

So three Naperville homeowners on three township lines are in three different spots right now. One can still file, one missed the window last month, and one hasn't been given a date yet. If you're under contract on a Naperville Township home, ask the seller whether they received a notice and whether they plan to appeal before the 13th. That decision feeds into the 2026 assessment, which drives the bill you'll pay in 2027.

In DuPage, a residential appeal goes through SmartFile. You create an account, choose "Residential Property Appeal," search by PIN without hyphens or spaces, attach your evidence and submit. The county recommends at least three comparable properties, with recent sales if you're arguing market value.

What a $500,000 home looks like code by code

To make the rates concrete, we modeled a $500,000 home assessed at one-third of market value, with no exemptions. These are illustrations, not real bills. Exemptions, the actual assessment and any appeal results will change a specific parcel's number. Both counties' final 2025 state multipliers were 1.0000, so the model doesn't need a statewide adjustment.

DuPage's code 7025 and Will's code 0714 are about $215 apart on this model home. Will's codes 0711 and 0714 are about $458 apart, more than double that, even though both sit in the same township of the same county.

A buyer who filters by county to save on taxes could end up on the higher-cost side of the Will County codes.

Why two Wheatland codes land so far apart

A tax code is a list of the taxing bodies that bill a parcel. Change the list and the rate changes.

Code 0711 includes the Forest Preserve, the Community Mental Health Board, Wheatland Township town and road funds, School District 204 at 4.5828, Community College District 502, the City of Naperville at 0.3977, the Naperville Park District at 0.2707, the Naperville Public Library at 0.1655 and Will County at 0.4834.

Code 0714 has a different list. It has no City of Naperville line and no library line. Instead it carries the Naperville Fire District at 0.2883, alongside the same school district, park district, college and county. Code 0713 includes the city and library but has no park district line.

Then there's how the bill is weighted. In code 0711, School District 204 makes up 73.5% of the total rate. Will County's own line is 0.4834. When one taxing body accounts for about three-quarters of the bill, the county is a small part of the total. Which bodies serve the parcel matters far more.

The DuPage Treasurer's office makes the same point in general terms. A parcel's tax code, its taxing bodies and its exemptions determine its bill.

The 2026 factors are already set

The rates above are last year's. Next year's bill is already taking shape through equalization factors, and those differ by county.

DuPage applied a 2026 factor of 1.0676 to Naperville Township parcels. The county describes the factor as the multiplier that brings the weighted three-year average level of assessment to the statutory level, applied to both land and improvements. Will County set Wheatland's 2026 factor at 1.0520, applied to residential property only, based on a three-year sales-ratio study. For tax year 2026, payable in 2027, Naperville Township assessments go up by a slightly larger factor than Wheatland's.

A higher assessment doesn't translate one-for-one into a higher bill. DuPage's 2025 cycle shows why. Countywide assessed value rose 8.2%, the average tax rate fell 4.37%, and the overall tax bill rose 3.83%. The Treasurer noted that individual bills vary by property and location. That's also why code 7025 dropped from 6.1328 for 2024 to 5.8307 for 2025. When assessed values rise, rates tend to fall to match the levies the taxing bodies requested. The Naperville Township assessor says the same thing directly: an assessed value isn't a tax bill forecast, because exemptions and rates also shape the bill.

The levies are moving too. District 203 adopted a $315.13 million levy for 2025 in a 5–2 vote, a 3.8% increase. Its CFO estimated the average increase for existing taxpayers at 2.9%, NCTV17 reported in December 2025. In March 2026, voters approved $120 million in Naperville Park District bonds. The district estimated the cost at an extra $117 a year for a $500,000 home, according to the Daily Herald. Code 0713, which has no park district line, wouldn't carry that bond cost.

Reading the tax line on a Naperville listing

The tax figure on a listing sheet is a past bill for one parcel, shaped by that owner's exemptions. Here's how to turn it into something you can compare:

1. Get the PIN and tax code. The code is what tells you which bodies tax the home. A street address or "Naperville" in the city field won't.
2. Look up the code's rate. For DuPage parcels, use the County Clerk's 2025 rate booklet. For Will parcels, use the Will County Clerk's posted 2025 rates.
3. Check the township's 2026 factor and appeal status. Naperville Township's deadline is October 13. Wheatland's window has closed. Lisle's hasn't been posted.
4. Ask which exemptions the seller claims. Your bill will reflect your own exemptions, not theirs.
5. Compare homes code to code. Two listings with the same price and different codes can differ by hundreds of dollars a year before the house itself even enters the picture.

Questions buyers ask about this

Is the Will County side of Naperville always more expensive in taxes?

No. In our 2025 model, Will code 0711 came out about $673 above DuPage code 7025, while Will code 0714 came out only about $215 above it. The taxing bodies on the code account for most of that spread.

Can a buyer appeal a home they don't own yet?

DuPage's process is set up around the property's PIN and the current owner's filing. For a Naperville Township home under contract right now, the practical step is asking the seller about the October 13 deadline. Talk to a qualified tax professional or attorney about your own situation.

Why doesn't the Will County assessor's site show 2025 rates?

The Will County Supervisor of Assessments homepage still says 2025 rates haven't been set. The Will County Clerk has posted them, though, and the Wheatland report is dated April 9, 2026. Use the Clerk's tables.

Comparing two Naperville homes and not sure which tax code each one carries? Tim Good Group can pull the PIN, tax code and 2026 township factor for any listing you're weighing. If you own in Naperville Township and wonder whether your new assessment matches the market, start with "What's My Home Worth?" and get the comparable sales before October 13.

This article is general information, not legal, tax or financial advice. Consult a qualified professional about your situation.