CSIM
Incentive Program

Affordable Housing Special Assessment Program (AHSAP)

CountyAssessment freeze, tiered by neighborhood market
What it is

AHSAP (administered by the Cook County Assessor) freezes the assessed value of qualifying multifamily rental buildings that maintain affordability. Replaces legacy Class 9 for most use cases.

Start with an address

Check an Address — Free Snapshot

See whether a specific Chicago address sits inside the area that unlocks Affordable Housing Special Assessment Program (AHSAP), alongside every other incentive that touches that parcel.

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Who it's for

Owners of multifamily rental buildings (typically 7+ units) who commit to affordability set-asides and complete qualifying capital investment. Three tiers (Tier 1/2/3) calibrated to neighborhood market conditions.

Where it applies

Affordable Housing Special Assessment Program (AHSAP) is administered at the county level. Depending on the program, eligibility may depend on the specific location, property type, or business activity rather than a single drawn boundary.

Boundaries are precise and change over time, so exact eligibility always depends on the specific address. The fastest way to know is to run a free snapshot for the parcel you have in mind.

What it can support

Typical range · Assessment freeze, tiered by neighborhood market

  • +Assessment reduction tied to affordability commitment
  • +Tier 1 / Tier 3 thresholds based on per-square-foot capital expenditure
  • +2026 thresholds: $8.16/sf (Tier 1) and $12.75/sf (Tier 3) for compliance + replacement of 2 primary systems
  • +Multi-year benefit; renewable with continued compliance
How to apply
  1. 1Confirm tier eligibility based on building location and affordability commitment
  2. 2Submit Part 1 application by September 5 of the assessment year
  3. 3Submit Part 2 application with capital expenditure documentation
  4. 4Maintain affordability covenant for duration of benefit
Fastest first move

Call (312) 603-7529 or visit cookcountyassessoril.gov/affordable-housing before Sept 5 deadline

What you'll need
  • Part 1 + Part 2 application forms
  • Affordability covenant / rent restriction agreement
  • Capital expenditure documentation meeting per-sf threshold
  • Documentation of replacement of 2 primary building systems
  • Annual recertification of affordable units
What to verify

This page is a starting point, not eligibility, legal, or tax advice. Verify current requirements, deadlines, and boundaries with the administering agency before applying or spending money — program rules and funding change over time.

Official source & contacts
Official program source ↗
Cook County Assessor's Office — Affordable Housing (CCAO-AH)

Last verified 2026-05-21

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Check an Address — Free Snapshot

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