Boone County, Illinois

Tax Lien53,313 residents

County research last verified 2026-07. Office holders, platforms, and deposit rules change — re-confirm anything time-sensitive.

Sale typestate default

Tax Lien

Redemption periodstate default

2–2.5 years depending on property type

Investor returnstate default

Up to 36% penalty per 6-month period (bid-down), 18% max per period at auction

Governing statutestate default

35 ILCS 200, Art. 21

Notes

Illinois annual tax-lien county. Boone County Treasurer sells certificates of purchase on unpaid taxes at an in-person open-outcry annual sale (single-bidder registration). Next sale: October 29, 2026; prior 2025 sale Oct 30 (278 parcels offered). $250 registration fee + Single Bidder Affidavit due ~10 business days before sale. County as trustee buys unsold liens — no scavenger sale. Belvidere / Rockford MSA fringe market.

Auction logistics

Format

In-person (open outcry; physical presence required)

Frequency

Annually late October (2026: October 29)

Platform

Boone County Treasurer — Annual Tax Sale ↗

Deposit rules

State law requires registration. $250 registration fee + Single Bidder Affidavit must be received ~10 business days before sale; fee applied to purchases, refunded if you attend and bid but buy nothing, forfeited if you do not attend. Payment immediately after sale: cash, check, cashier's check, or money order. PDF delinquent list ~$70 ~10 days prior.

Title risk

Liens that survive the sale

Buyer receives a certificate of purchase, not ownership. Owner redemption extinguishes the claim (penalty can reach high teens % per Illinois schedule). Tax deed requires court petition after redemption period.

Quiet title

Tax-deed petition process is the primary clearing step; additional quiet title may still be used for resale insurance.

Deal maths for Illinois

Assessment ratio: 0.3333× of market value
Typical quiet title: $1,800–$5,000 · 5 mo
Recording and transfer: $350

35 ILCS 200/9-145: property outside Cook County is assessed at 33⅓% of fair cash value.

Offices and records

Tax collector

Boone County Treasurer ↗

815-544-2666

Clerk of court

Boone County Clerk (redemption 815-544-3103) / Circuit Clerk (tax deed) ↗

Property appraiser

Boone County property tax inquiry ↗

GIS / parcel map

Boone County property tax / parcel inquiry ↗

Areas trending up

Directional read from dated market analysis — not a guarantee, and not a substitute for your own comps.

Belvidere city / industrial corridor

Manufacturing employment and Rockford MSA spillover with liquid SF

I-90 / Genoa Road fringe

Commute access toward Rockford–Chicago with newer housing pockets

Poplar Grove / northern Boone

Relative-value residential with regional job access