Where we work
Service Areas
NorthPeak is based in Wilmette and works with businesses across Chicago's north suburbs in person, and with clients nationwide remotely. Below is where we are most often — and, because it matters more than most owners expect, who actually assesses property in each one.
Cook County
9 communitiesAssessed by the Cook County Assessor. Every one of these sits in the north suburban triennial group — reassessed 2016, 2019, 2022 and 2025, so the next is 2028.
Evanston
Glenview
Northbrook
Niles
Park Ridge
Lake County
2 communitiesAssessed by the township assessor, not a county assessor. Cook is the exception in Illinois; every other county works this way, and Lake asks you to contact that township office before filing an appeal.
Deerfield
Highland Park
Both counties
1 communitiesSplit at Lake Cook Road — Cook County system to the south, Lake County system to the north, with different sales tax rates either side.
Wheeling
Two details worth knowing
Both come up more often than you would think, and both change the answer to a simple question.
Wheeling is split down the middle
Lake Cook Road is the line. South of it, assessment runs through the Cook County Assessor and the Cook County Treasurer collects. North of it, Lake County's Chief County Assessment Office and Treasurer handle it. The village publishes the sales tax consequence too: the Cook portion carries a 10% total rate and the Lake portion 8%. If you sell taxable goods in Wheeling, which side of that road your counter sits on is a real number on your return.
Village source →Glenview sits in three townships
New Trier, Niles and Northfield all cover parts of the village. Two businesses on opposite sides of Glenview can fall into different township assessment groups, so a reassessment year for one is not automatically a reassessment year for the other. Worth confirming by parcel rather than by village name.
Cook County Property Tax Appeals: What North Suburban Business Owners Should Know
Cook County reassesses the north suburbs every three years. What that means if your business owns its building, and wher…
Cook County vs. Lake County: What Changes for a Business at the Line
The county line runs through the north suburbs. Who assesses your property, how you appeal, and what you charge in sales…
Sales Tax in Wheeling: Which Side of Lake Cook Road Are You On?
Wheeling is split between Cook and Lake counties at Lake Cook Road, and the total sales tax rate differs by two points a…
Not on the list?
Most of the work is done remotely, so the table above is about where we turn up in person — not where we can help. If you are elsewhere in Illinois or in another state, the answer is almost always yes.