County Building Permits

Washington County, MO - 2026 Building Permit Guide

Building permit information for unincorporated Washington County and all incorporated cities. Find your jurisdiction's permit authority, application process, fees, and requirements.

Missouri Updated March 2026

Important: Washington County issues building permits only for properties in unincorporated areas of the county. If your property is inside an incorporated city, select your city below — that city's building department handles your permits, not the county.

Unincorporated Washington County

Permit authority
No countywide building permit department publicly found; Washington County government pages reviewed did not show a building permits office
Website
None found
Online portal
None found
Phone
573-438-6111
Address
102 N Missouri St, Potosi, MO 63664

Jurisdictions in Washington County

Select your jurisdiction for local permit authority, portal links, application steps, fees, and inspection requirements.

Unincorporated Washington County Permit guide → Caledonia Permit guide → Irondale Permit guide → Potosi Permit guide →

Information on this page was last verified: March 2026. Permit rules and fees change — confirm current requirements directly with the relevant city or county department before applying.

Related Missouri Resources

License Requirements Verify your contractor's Missouri license → Contract Template Free homeowner-contractor agreement →

Need help with your project?

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Important: This page is an educational resource provided by jaspector.com. It is not legal advice, and it does not substitute for official guidance from the permit authorities listed above. Permit requirements, fees, and processes change frequently. Always verify current requirements directly with the issuing department before beginning any construction project. Use of this page does not create an attorney-client relationship. Jaspector assumes no liability for any outcomes arising from reliance on this information.