Straight Answers: My McHenry County Property Assessment Went Up. Now What?

If you just opened a McHenry County assessment notice and the number went up, here is the short answer: this is a reassessment year, and a higher assessment does not automatically mean a higher tax bill. You have 30 days from the date on your notice to file a complaint with the McHenry County Board of Review if you believe the value is too high. And you can file on your own, without hiring anyone.

This fall, thousands of homeowners across McHenry County are getting the same envelope, and most of them have the same questions. Let me walk you through what the notice actually means and what to do next. That is what I would do if you were sitting at my kitchen table.

Why did my assessment go up?

McHenry County reassesses properties on a regular cycle, township by township, and 2026 is one of those years. Assessment notices went out across the county in waves this summer and fall, and the reassessment is designed to bring your assessed value in line with what similar homes in your area have actually been selling for, as of January 1 of this year.

After a few years of rising home prices, that catch-up often shows up as an increase. It is not a penalty, and it is not a prediction. It is the county restating what it believes your home is worth. Once you see it that way, the notice becomes a lot less intimidating.

Does a higher assessment mean my taxes jump by the same amount?

No, and this is the part that confuses the most people. Your assessment is your share of the pie. Your actual tax bill is set by the levies of the local taxing bodies, the overall tax rate, and how your assessed value compares with everyone else's in the township.

If assessments rise across your area, the rate can shift to offset part of that increase. So the number on the notice does not guarantee an equal increase in your bill. Read the notice carefully, but do not let the displayed figure alone get you worked up before you understand the whole picture.

When does this assessment affect my tax bill?

Here is the timing that surprises a lot of homeowners: this year's assessment sets the taxable value for property taxes due next year. It does not change the bills you already paid this year.

So if your assessment went up this fall, the effect will show up in next year's tax bill, and only to the extent the numbers support it. You are not being asked to pay anything today, and nothing about the bill you already paid changes.

Do I have to appeal? What happens if I do nothing?

You do not have to do anything, and filing just to file is not a good use of anyone's time. If the value on the notice looks fair compared with what similar homes nearby have sold for, you are probably fine exactly where you are.

Your General Homestead Exemption keeps working for you as long as you own and occupy the home as of January 1. It reduces the equalized assessed value of an owner-occupied home by up to $8,000, with no age requirement. That protection does not go away in a reassessment year.

But if the number looks out of line with the market, the appeal process exists precisely for that situation. In my experience, that is usually when a reassessment notice becomes worth acting on.

How do I appeal?

Appeals run through the McHenry County Office of Assessments, and complaints are filed online through the county's Property Tax Inquiry portal. The county's Assessments page at mchenrycountyil.gov/departments/assessments has the official complaint form and step-by-step instructions.

For a residential appeal, you will fill out the complaint form and a comparable sales grid with at least three sales of similar homes, as close to January 1 of this year as you can find. Photos help. A recent independent appraisal helps even more, if you happen to have one.

And one honest warning: the Board of Review can confirm an assessment, reduce it, or increase it. An appeal is not a one-way door. Come with real evidence, not just the hope of a lower number, and the process is fairly straightforward.

What should I do today?

1. Find the date on your notice. Each township has its own 30-day window, which starts when that township's notices are published. Deadlines are not all the same, so check the date on your notice and the county's posted schedule. Do not wait until the last week.
2. Pull two or three comparable sales. Sales of similar homes nearby, ideally closed around the beginning of this year, are the evidence that matters most.
3. Decide with a clear head. If the assessment looks fair, do nothing. If it looks high, file before your window closes. That is the whole decision.

Do I need to hire someone to appeal for me?

Many homeowners handle this themselves, and the county lays out exactly what to submit. Hiring a tax consultant is your call, and I am not here to talk you out of it. But you should know the process is designed for homeowners to use directly. Start by reading the county's instructions. You may find you do not need to pay anyone.

What does this have to do with selling?

If you have been thinking about selling, here is the connection worth understanding. Your assessment is the county's opinion of your home's value for tax purposes. It is not what a buyer will pay, and it is not the starting point for a well-prepared listing. But when the two are far apart, it usually means the market has moved, and that is useful information.

If you are looking at your notice and wondering what your home would really bring, that is a different kind of conversation, and it is one I am glad to have. No obligation, no pressure. My job is to replace that stress with clarity.

If you are in Lake County instead, the rules work differently, and I have written about that here: Straight Answers: Your Property Tax Assessment Notice Arrived. Now What?

The bottom line

A reassessment notice is not an emergency. Read the number, check the date, and decide whether the value looks fair. If it does not, McHenry County gives you 30 days and a process you can handle yourself. If it does, you have lost nothing but a few minutes.

And if you are also weighing whether to make a change, that is what I am here for: straight answers, calm guidance, and more than 50 years of perspective on the Lake County and McHenry County market. Building lifelong relationships, one home at a time. I would be honored to help you, too.