TaxDriftIndex
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FIPS: 17031Rank #1 NationalRank #1 in IL

Cook County, IL

Forward-Looking Municipal Debt, Assessment Lag & Carrying Cost Audit

Severe Tax Drift Risk
96% Conf.
Tax Drift Index
86.4/ 100
Severe Drift Risk
Cook County Executive Risk Briefing
MSRB EMMA Disclosures & US Census BureauAugust 2026

Cook County carries a Severe Tax Drift Score (86.4/100) based on $12,400 in overlapping municipal debt per capita and a +31.4% CAD assessment lag spread. Projected 3-year millage escalation of +0.41% (+41 bps) indicates an estimated +$3,053/yr escrow adjustment on median-priced properties.

Median Home: $310,000Median Income: $78,500Effective Tax: 2.4%
Municipal Debt Per Capita
$12,400
15.8% of Median Income
CAD Valuation Lag
+31.4%
Assessed Value trailing Market HPI
3-Yr Millage Escalation
+41 bps
Effective Rate: 2.4%2.8%
Projected Annual Escrow Shock
+$3,053/yr
Estimated on median assessed home

Overlapping Taxing Jurisdictions & Debt Obligations

Breakdown of autonomous debt issuers assessing ad valorem property taxes on parcels within Cook County.

Entity NameEntity TypeOutstanding Bond DebtDebt / Student or CapAdopted Millage
Chicago Public Schools (District 299)ISD$8.9B$27,500112.000%

5-Year Historical Drift Score & Effective Rate Trajectory

2022
76
2.2% eff.
2023
79
2.3% eff.
2024
82
2.3% eff.
2025
85
2.4% eff.
2026
86.4
2.4% eff.
Statutory Constraint & Legislative Policy

Home-rule status allows City of Chicago and Cook County to supersede PTELL property tax extension caps.

Data Provenance & Audit Citations