County Building Permits

Franklin County, MO - 2026 Building Permit Guide

How to apply for a building permit in unincorporated Franklin County, Missouri. Permit authority, application steps, fees, and inspection requirements.

Missouri Updated March 2026

Permit Authority

Covers unincorporated Franklin County; the department issues permits and enforces the 2021 IBC/IRC suite, 2020 NEC, 2021 swimming pool/spa code, and the county's Flood Damage Prevention and Unified Land-Use regulations listed on the same page. 【0†source】citeturn1view0

Department: Franklin County Building Department (the county issues and inspects permits for new structures in the unincorporated area and enforces the county codes listed below). 【0†source】citeturn1view0
Address: 400 E Locust, Room 006, Union, MO 63084. 【0†source】citeturn1view0
Phone: (636) 583-6384. 【0†source】citeturn1view0
Email: building@franklinmo.gov. 【0†source】citeturn1view0
Website: https://www.franklinmo.org/building-dept. 【0†source】citeturn1view0

Online Permit Portal

Open https://www.franklinmo.org/permits (the county's central permit landing page for all construction/ROW categories). 【0†source】citeturn2view0

Platform: Franklin County Government Permits web page. 【0†source】citeturn2view0 • Account required: No • Submission: In-person only

Additional resources:

Application Process

General Requirements

Work That Does NOT Require a Permit

Contact the Franklin County Building Department (the county issues and inspects permits for new structures in the unincorporated area and enforces the county codes listed below). 【0†source】citeturn1view0 to confirm whether your project requires a permit before starting work.

Inspections

How to Schedule

Additional Resources

License lookup guide: Missouri Contractor License Requirements
Contract template: Missouri Homeowner-Contractor Agreement
Missouri hub: Missouri Contractor License & Permit Hub

Information on this page was last verified: March 2026. Permit rules and fees change — confirm current requirements directly with the Franklin County Building Department (the county issues and inspects permits for new structures in the unincorporated area and enforces the county codes listed below). 【0†source】citeturn1view0 before applying.

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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 authority 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.

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