Mills Act Contracts: Chicago vs Des Plaines
How do mills act contracts rules compare between Chicago, IL and Des Plaines, IL?
Chicago and Des Plaines have similar restriction levels.
Chicago, IL
Cook County
Illinois has no equivalent to California's Mills Act. Chicago landmark owners instead use the Class L property tax incentive under 35 ILCS 200/15-40 and Cook County Assessor rules, freezing assessed value for twelve years on rehabilitated landmarks.
View full Chicago rules →Des Plaines, IL
Cook County
Illinois has no statute equivalent to the California Mills Act. Instead, Illinois Property Tax Code 35 ILCS 200/15-40 and Cook County Class L assessment incentive provide property tax reductions for landmarked rehabilitation projects, freezing valuations rather than reducing rates.
View full Des Plaines rules →Key Facts Comparison
| Fact | Chicago | Des Plaines |
|---|---|---|
| State authority | 35 ILCS 200/15-40 | - |
| Local program | Class L incentive | - |
| Freeze duration | 8 years plus 4 phase-up | - |
| Investment threshold | Half of building value | - |
| Reviewing agencies | Landmarks Commission and Assessor | - |
| Mills Act equivalent | - | None in Illinois |
| State statute | - | 35 ILCS 200/15-40 |
| State freeze | - | 8 years plus 4-year phase |
| Class L term | - | 12-year freeze |
Highlighted rows indicate differences between cities.
Chicago FAQ
Can I get a Mills Act contract in Chicago?
No. Illinois lacks Mills Act authority. The closest equivalent is Class L, which is a frozen-assessment incentive rather than a contract-based reduction. Apply through the Commission on Chicago Landmarks first.
What rehabilitation qualifies for Class L?
Substantial rehab worth at least 50 percent of the building's market value, completed under a Commission-approved scope using preservation standards. Routine maintenance and cosmetic work alone do not qualify.
Des Plaines FAQ
Can I get Mills Act-style benefits in Cook County?
No. Illinois uses an assessment freeze rather than a formula-based cap. The 35 ILCS 200/15-40 program and Cook County Class L are the closest equivalents available.
Which program fits my home?
Owner-occupied historic homes typically use the state 35 ILCS 200/15-40 freeze. Commercial or rental landmark properties usually pursue Cook County Class L through the Assessor.
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