County permits

Mercer County

Mercer County issues permits only for unincorporated areas. Inside an incorporated city? Pick the city below — its building department handles your permit.

§ 01 Unincorporated

Unincorporated Mercer County.

If your property isn't inside an incorporated city, the county permit office handles your application directly.

Permit authority: Mercer County Zoning Office
Website: Mercer County Zoning Office ↗
Online portal: Mercer County Zoning Office ↗
Phone: 309-525-3799 (Zoning Officer Cell) / 309-582-5353 (Main Office)
Email: zoning@mercercountyil.org
Address: 100 SE 3rd St, Aledo, IL 61231

Full unincorporated Mercer County permit guide →

§ 02 Jurisdictions

Cities in Mercer County

Click any city for its full permit guide — authority, fees, application steps, inspections, and exempt work.

§ 03 County navigation

Information last verified for Mercer County, Illinois. Permit rules and fees change frequently — verify current requirements with the issuing department before applying. Jaspector is an educational reference, not legal advice.