Cook County reassesses on a three-year rotation. The South and West suburbs are being reassessed now. Chicago is next, in 2027, for the first time since 2024.
The 2024 cycle is in the Board of Review's published decision history, township by township:
- **Lake View:** 74,551 decisions in 2024; 98.6% attorney-filed; 49.9% reduction rate.
- **North Chicago:** 67,821 decisions in 2024; 99.6% attorney-filed; 33.3% reduction rate.
- **West Chicago:** 63,951 decisions in 2024; 96.7% attorney-filed; 45.9% reduction rate.
- **Jefferson:** 56,048 decisions in 2024; 87.5% attorney-filed; 48.0% reduction rate.
- **South Chicago:** 53,611 decisions in 2024; 96.8% attorney-filed; 33.8% reduction rate.
- **Lake:** 24,774 decisions in 2024; 69.9% attorney-filed; 52.9% reduction rate.
- **Hyde Park:** 19,176 decisions in 2024; 94.7% attorney-filed; 46.1% reduction rate.
- **Rogers Park:** 12,915 decisions in 2024; 96.9% attorney-filed; 44.3% reduction rate.
372,847 decisions in the city in one tax year, against 154,898 the year before. The 2021 cycle produced 339,637 and the 2018 cycle 364,832. Chicago reassessment years run between 340,000 and 375,000 Board decisions, and they arrive in eight township windows of about a month each.
A firm that waits for the 2027 notices will build its city book in those windows. A firm that starts now has a year. Here is what the year is for.
Quick Answer
Chicago's 2024 reassessment produced 372,847 Board decisions (against 154,898 the year before). The next city cycle is 2027. Across 2023-2025, West Chicago commercial alone saw $1.50 billion in assessed value reduced; South Chicago saw $3.11 billion. A firm that starts now has a year for authorizations, PIN reconciliation, commercial packets, and hearing-capacity allocation.
Where the commercial money was
The city's commercial and industrial book, tax years 2023 through 2025, is the largest in the county:
- **West Chicago:** 22,028 commercial decisions; 6,271 reduced; 1,363 at $100,000+ AV; total AV reduced $1.50 billion.
- **Jefferson:** 16,444 commercial decisions; 4,899 reduced; 568 at $100,000+ AV; total AV reduced $358 million.
- **Lake:** 10,998 commercial decisions; 3,804 reduced; 402 at $100,000+ AV; total AV reduced $213 million.
- **South Chicago:** 7,733 commercial decisions; 3,804 reduced; 1,212 at $100,000+ AV; total AV reduced $3.11 billion.
- **Hyde Park:** 6,823 commercial decisions; 1,948 reduced; 244 at $100,000+ AV; total AV reduced $144 million.
- **Lake View:** 6,436 commercial decisions; 1,681 reduced; 345 at $100,000+ AV; total AV reduced $189 million.
- **North Chicago:** 5,006 commercial decisions; 2,626 reduced; 846 at $100,000+ AV; total AV reduced $1.37 billion.
South Chicago produced fewer than half of Jefferson's commercial decisions and nearly nine times the assessed value in reductions, because the industrial corridors along the lake and the river are there. North Chicago, the Loop and the Near North, put $1.37 billion of assessed value back in about five thousand files. In 2027 those parcels will be revalued, and the packets that won in 2024 have owners who know it.
Twelve months of work that does not need a notice
**1. Mine the 2024 record.** Every city parcel that appealed in 2024 has a public decision: what was argued, what was granted, what the value became. Parcels that won know the process works and have evidence on file. Parcels that were denied may be ready to try with different counsel. A paralegal can build the township-by-township prior-appellant list over the winter.
**2. Watch the 2025 and 2026 sales against the 2024 values.** The 2027 model will train on sales through the end of 2026. A neighborhood selling below its 2024 values is likely to see the reassessment do the reduction itself, and a smaller appeal. A neighborhood selling above them is where the increases and the phone calls will be. The Assessor's parcel sales are on the county's open data portal.
**3. Stage the authorizations.** Rule 2 requires the Attorney Authorization Form before finalization, with no late acceptance. Rule 1 requires entities, including condominium associations, to be represented by an attorney. For a city book heavy in associations and LLCs, the winter is the time to get the current form signed by the right signer.
**4. Reconcile PINs.** Rule 9 requires all related PINs on one complaint, and Chicago's condominium stock makes that rule bite: units, deeded parking, storage, common elements. Build the PIN map for each association from the county's record now. Then read the condominium record for the township before promising anything; in 2023 through 2025, attorney-filed condo appeals in Lake View were reduced 41 percent of the time, in South Chicago 28 percent, in North Chicago 31 percent.
**5. Collect the commercial packets.** Rule 14B requires a complete Historical Summary Form; Rule 20 asks for three years of Schedule E or the entity equivalent, rent rolls with totals, and representative leases. For 2027, the three years are 2024, 2025, and 2026. Two exist today.
**6. Allocate hearing capacity by township.** Rule 12 caps an attorney at eight dockets per call and 45 hearings per group. A firm with a real Lake View book needs to know before the township opens how many codes it will file under.
What not to do yet
Do not promise a 2027 reduction; the values do not exist. Do not file 2026 Board appeals on city parcels as placeholders; 2026 is not a city reassessment year, and the Board's 2026 windows are for 2026 values. And do not assume the 2027 township order will match 2024's. The Assessor publishes the schedule when the office is ready, and the model documentation for 2024 shows the office used one model run for Rogers Park and West Chicago and a second for the rest of the city, so even the modeling can differ across the cycle.
The quiet advantage
Every firm in the city will be busy in the thirty days after each township's notice mails. The calm ones will be those whose authorizations are signed, whose PIN maps are built, whose commercial packets are two-thirds assembled, and whose hearing capacity is already allocated. None of that needs the notice.
The numbers behind this article
Decision counts, attorney shares, reduction rates, and assessed-value totals are Censum's tabulation of the Cook County Board of Review Appeal Decision History dataset (county open data, 7pny-nedm), copy dated May 20, 2026; PIN-level decisions, tax year 2025 incomplete. The reassessment rotation and the 2024 model notes are from the Assessor's published materials. Censum is independent and not affiliated with the Assessor, the Board, or any county office. Censum's opportunity queues surface prior appeal history, sales movement against current values, and related-PIN groupings by township, so the prep runs on the firm's calendar rather than the county's.
Sources
- Cook County Board of Review Official Rules
- Cook County Assessor Assessment Calendar
- Censum tabulation of the Cook County Board of Review Appeal Decision History dataset (Cook County open data, 7pny-nedm), copy dated May 20, 2026; PIN-level decisions; tax year 2025 incomplete in that copy.
- Rules cited: Cook County Board of Review Official Rules 1, 2, 9, 12, 14B, 20, last updated July 27, 2026.
FAQ
How large were the 2024 Chicago township Board books?
Lake View 74,551; North Chicago 67,821; West Chicago 63,951; Jefferson 56,048; South Chicago 53,611; Lake 24,774; Hyde Park 19,176; Rogers Park 12,915.
Should a firm file 2026 Board appeals on city parcels as placeholders for 2027?
No. 2026 is not a city reassessment year, and the Board's 2026 windows are for 2026 values. Do not promise a 2027 reduction; those values do not exist yet.
Which Schedule E years matter for a 2027 commercial complaint?
Rule 20's three years prior to the lien date: 2024, 2025, and 2026. Two of those exist today.
Does Censum file or represent clients?
No. Censum LLC is independent property-tax intelligence and docket tooling. It is not a law firm. The attorney files and makes every legal judgment.
Next step
Look up the firm's city book by township: prior 2024 appeal outcomes, sales against 2024 values, related-PIN groups, and unsigned authorizations. None of that work needs the 2027 notice.
Censum LLC is independent and not affiliated with Cook County or any government agency.