Property tax in Lake County, Illinois
In Lake County, the property tax bill comes from the Lake County Treasurer. Every due date for the 2025 bill has passed, and the county had not posted the next cycle's dates when we checked. You can look up and pay the bill on the county's own payment page. Taken from Lake County's own pages, checked September 23, 2026.
The median property tax bill in Lake County, Illinois is $8,923 a year, which is about 2.58% of the county's median home value of $345,700. That effective rate is higher than the typical Illinois county (1.81%) and higher than the national median (0.81%). These are American Community Survey 5-year estimates (2024); your own bill depends on your home's assessed value and any exemptions.
Who sends the property tax bill in Lake County, and how do you pay it?
The bill comes from the Lake County Treasurer. The value it is based on is set by a separate office, the Lake County Chief County Assessment Office (values are set first by the township assessor's office), which is who to ask if the value looks wrong. For how to look up and pay the bill, go to the county's own payment information.
The Treasurer mails one bill a year, with a coupon for each installment, and it covers every local government that taxes your home; Lake County has more than 200 of them. Your home is valued first by your township assessor, and the county asks owners to talk to that office before filing an appeal. Appeals to the Board of Review must be filed online, no attorney is needed for a home, and the deadline differs by township. The exemptions on the county's tax relief pages (general homestead, seniors, veterans and disabled persons, home improvement) are the state's programs, applied for through the county. Online card payments carry a processor fee of 2.35% for credit cards or PayPal and 1.5% for debit cards; e-checks are free. Online payment is open only during part of the collection period and only for the current tax year.
When are property taxes due in Lake County?
Every due date for the 2025 (payable in 2026) bill has passed, and Lake County had not posted the next cycle's dates when we checked on September 23, 2026. If that bill is still unpaid, the late-payment rules below apply to it. Counties usually repeat the schedule, but confirm the new dates on your next bill. For the 2025 (payable in 2026) bill, Lake County splits the bill into 2 payments, the first due June 4, 2026 and the last September 4, 2026. State law charges interest (the county calls it penalty interest) of 1.5% a month, or any part of a month, on an unpaid installment, starting the day after its due date (June 5 and September 5) and again on the 5th of each following month. Taxes still unpaid are published in the newspaper on October 15, 2026; to avoid that, pay online by September 30 or at the Treasurer's office by 5:00 p.m. on October 2 (a $10 fee is added after that). To avoid the tax sale on November 13, 2026, payment must reach the Treasurer's office by 5:00 p.m. on November 12 in cash, money order or cashier's check; postmarks do not count.
| Payment | Due | Note |
|---|---|---|
| First installment | June 4, 2026 (passed) | Bills for tax year 2025 were mailed May 1, 2026, with a coupon for each installment. To pay the whole bill at once, send both coupons by the first due date. Mailed payments count if the envelope carries a U.S. Postal Service postmark (not a postage-meter stamp) on or before the due date. |
| Second installment | September 4, 2026 (passed) | September 4 was also the last day to pay at a local bank. |
From Lake County's published schedule, checked September 23, 2026. If a date falls on a weekend or holiday, the county's own rules on the next business day apply.
Estimate the property tax on a home in Lake County
Enter a home's market value for a ballpark at Lake County's average effective rate of 2.58% (Census). The real bill depends on the home's assessed value, the millage where it sits and any exemptions.
Estimated property tax: $8,919 / year
Property tax in Lake County at a glance
| Measure | Value |
|---|---|
| Median annual property tax | $8,923 |
| Median home value | $345,700 |
| Effective tax rate | 2.58% |
| Typical Illinois county rate | 1.81% |
| National median county rate | 0.81% |
Effective rate = median real estate taxes paid divided by median home value. Source: U.S. Census Bureau, American Community Survey 5-year estimates.
How does Lake County compare in Illinois?
Among Illinois's 102 counties, Lake County has the highest effective property-tax rate. That places it among the most heavily taxed counties in the state. Nationally, it ranks 9th of 3135 US counties by effective rate. See every Illinois county ranked.
How much do homeowners in Lake County actually pay?
The median is only the middle bill. Across Lake County's 193,403 owner-occupied homes, 89.3% pay $3,000 or more a year in property tax, 92% pay at least $2,000, and 3.3% pay under $800. Another 2.2% report paying no property tax at all, which usually means an exemption covers the whole bill.
| Annual bill | Homes | Share |
|---|---|---|
| Under $800 | 6,478 | 3.3% |
| $800 to $1,499 | 2,745 | 1.4% |
| $1,500 to $1,999 | 1,830 | 0.9% |
| $2,000 to $2,999 | 5,311 | 2.7% |
| $3,000 or more | 172,750 | 89.3% |
| No property tax paid | 4,289 | 2.2% |
Owners with a mortgage pay a median of $9,334 and owners without one pay $8,093. Owners who have paid off a home have usually held it longer, and in states that cap how fast an existing owner's assessment can rise, long-held homes carry lower assessed values. Census table B25103.
How does the Lake County property tax bill compare with local incomes?
The median property tax bill of $8,923 is about 6.6% of the median income of Lake County homeowner households, $134,561 a year. That compares two middles, so a retiree in a long-held home can pay a far larger share. 74.8% of Lake County's occupied homes are lived in by their owners; renters pay property tax too, just folded into rent.
Have property taxes gone up in Lake County?
Yes. The median bill went from $7,587 in 2015-2019 to $8,923 in 2020-2024, a 17.6% rise. Over the same span the median home value moved 30.4%, from $265,100 to $345,700. Bills rose more slowly than values, which is what assessment caps and falling millage rates do: the county is taxing a smaller share of each home's worth.
Two Census ACS 5-year periods with no survey years in common, in each period's own dollars. A change counts only if it exceeds the combined 90% margin of error.
Property tax in counties next to Lake County
Lake County borders 6 counties, 4 of them across the state line.
| County | Effective rate | Median bill | Median home value |
|---|---|---|---|
| Lake County, IL (this county) | 2.58% | $8,923 | $345,700 |
| McHenry County, IL | 2.36% | $7,274 | $308,100 |
| Cook County, IL | 1.91% | $6,191 | $324,500 |
| Kenosha County, WI | 1.57% | $4,179 | $265,500 |
| Van Buren County, MI | 1.23% | $2,536 | $206,500 |
| Allegan County, MI | 1.08% | $2,884 | $267,100 |
| Berrien County, MI | 1.08% | $2,429 | $224,300 |
How is a home assessed in Lake County?
Illinois assesses homes at 33.33% of market value in every county, Lake County included. How Illinois assesses and reappraises homes.
Is there a homestead exemption in Lake County?
Yes. Illinois's General Homestead Exemption is $6,000 of equalized assessed value in most counties, $8,000 in counties next to Cook, and $10,000 in Cook County. That is the Illinois rule, and it applies in Lake County. Illinois's exemptions and relief programs in full.
Lake County does not add relief programs of its own beyond the Illinois ones (checked September 23, 2026).
How to appeal your Lake County property assessment
In Lake County you appeal to the Lake County Board of Review. The deadline: Within 30 calendar days after the date your township's assessments are published in the newspaper; the deadline for your property is printed on your assessment notice. For 2026 the deadlines run township by township, from August 24, 2026 (Benton and Ela) to November 2, 2026 (Shields). How to file. Checked September 23, 2026 against the official appeal rules.
How Illinois's appeal process works, including the next level if the first one turns you down.
Illinois rules from primary state sources, reviewed September 7, 2026; sources on the Illinois page.
Work out your own numbers
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How much house can I afford?
Your income, debts and down payment against the 28/36 rule lenders actually use, with Lake County's tax rate to hand.
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Mortgage calculator
Monthly payment with principal, interest, tax and insurance, plus what an extra payment saves you.
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Illinois income tax
Brackets, standard deduction and what Illinois actually taxes.
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Sales tax in Lake County
The other local tax: combined state and local rate for this county.
Sources
- Median real estate taxes paid and median home value for Lake County, Illinois: U.S. Census Bureau, American Community Survey 5-year estimates (2020-2024), tables B25103, B25077, B25102, B25119 and B25003; the five-year comparison uses the 2015-2019 estimates. Neighboring counties: Census county adjacency file.