Building and Permits

The Building Division performs plan review and inspections on new residential and commercial properties. Residential permits are required for any new home, as well as for decks, sheds, pools, basement finishes, additions and major alterations. Residential rental occupancy permits are required before occupying the unit. Commercial permits are required for any new commercial project including alterations or additions. This division is also responsible for the planning and implementation of the City’s adopted building codes and ordinances.

Questions about permits? Check out our guide: Why do I need a permit? (PDF)

Apply for a permit     Account Login

The division is located on the second floor of O'Fallon Municipal Centre (City Hall), 100 North Main Street. Hours of operation are Monday through Friday, 8 a.m. – 5 p.m.

Scheduling an inspection can be completed by logging into the O’Fallon Permitting, Licensing, and Enforcement (OPLE) portal using the button above. Inspections scheduled using the portal are typically completed the next day. Rental occupancy inspections may require two (2) day’s notice prior to an inspection being conducted depending on when the request is received. Questions may be directed to 636-379-5660.

City of O'Fallon Permit Fee Schedule (PDF)

Current Codes and Adoptive Ordinances (PDF files)

• 2015 International Building Code
• 2015 International Residential Code
• 2015 International Existing Building Code
• 2015 International Fire Code
• 2015 International Mechanical Code
• 2015 International Fuel Gas Code
• 2015 International Plumbing Code
• 2015 International Energy Conservation Code
• 2015 International Property Maintenance Code
• 2015 International Swimming Pool and Spa Code
• 2015 International Private Sewage Disposal Code
• 2014 National Electric Code
• 2013 NFPA-Sprinklers
• 2009 ICC/ANSI A117.1 Accessibility

Other resources (PDF files)

• Open in the “O” brochure
• Why do I need a permit? brochure

Fire Districts

Please note:  The City of O'Fallon is served by multiple independent fire districts that are separate governmental entities and do not fall under the authority of the City of O'Fallon. These districts may require their own building permit. Please contact the appropriate district for more information. The districts are:

• Central County Fire & Rescue
• Cottleville Fire Protection District
• Lake Saint Louis Fire Protection District
• New Melle Fire Protection District
• O'Fallon Fire Protection District
• Wentzville Fire Protection District
• View a map of the fire districts (PDF)

Contact Building staff

If you have any questions or concerns, please contact the Building Division's main telephone line at 636-379-5660. You may also contact the employees below directly: