St. Louis Building Permits — Cost, Timeline & Process

The City of St. Louis requires a building permit for most construction, alteration, and repair work affecting structural, electrical, plumbing, or mechanical systems. Permits are issued by the Building Division — Department of Public Safety. The Building Division administers plan review, permit issuance, and field inspections for work within city limits; the Board of Public Service is a separate city body with its own public-service and right-of-way functions.

Critical jurisdictional note: The City of St. Louis is an independent city — it is not located within St. Louis County and has been a separate government since 1876. St. Louis County (a separate entity that surrounds the city) has its own building department and permit system. If your property has a St. Louis city address, you need a City of St. Louis permit from the Building Division. If your property is in unincorporated St. Louis County or a county municipality, you need a county or municipal permit instead. These are entirely distinct governments with no shared permitting jurisdiction.

The City's current adopted construction-code package includes the 2018 IBC, 2018 IRC, 2018 IEBC, 2018 IECC, 2018 IMC, and 2018 International Fuel Gas Code, together with the 2021 Uniform Plumbing Code and 2017 National Electrical Code, all with local amendments. Missouri does not impose one statewide residential building code for every municipality, so the City's locally adopted package controls within St. Louis city limits.

When You Need a Permit

You generally need a City of St. Louis building permit for:

• New construction, additions, and accessory structures (including ADUs)
• Structural alterations, load-bearing wall changes, and foundation work
• Electrical, plumbing, and mechanical (HVAC) system changes
• Reroofing and exterior wall openings for windows or doors
• Swimming pools, spas, and retaining walls above applicable height thresholds
• Demolition of any habitable structure
• Fences and accessory structures above certain size or height thresholds
• Change of occupancy or use, even without physical alterations

Minor cosmetic work (painting, floor coverings, cabinetry without plumbing or electrical changes) is typically exempt. When in doubt, contact the Building Division before starting work — unpermitted work can result in stop-work orders, fines, and required demolition.

Building Division

The Building Division is part of the Department of Public Safety and serves as the City's permit-issuing and inspection authority for building and related construction work.

Key functions of the Building Division include:

• Accepting and processing permit applications
• Conducting plan review for code compliance
• Issuing building, electrical, plumbing, and mechanical permits
• Scheduling and conducting required field inspections
• Issuing Certificates of Occupancy upon final approval

For most residential and commercial permit inquiries, contact the City of St. Louis Building Division at stlouis-mo.gov/government/departments/public-safety/building-division/.

Permit Costs

City of St. Louis building permit fees are established by city ordinance and calculated based on project valuation. Typical fee components include:

• Building permit fee — scales with the declared project valuation
• Plan review fee — a percentage of the building permit fee for projects requiring plan check
• Trade permit fees — separate fees for electrical, plumbing, and mechanical permits
• Inspection fees — included in or supplemental to the building permit fee depending on project type

Do not rely on third-party fee estimates. Always consult the current fee schedule published by the Building Division at stlouis-mo.gov or contact the Building Division directly for exact amounts before budgeting your project.

Review Timing

The City does not publish one guaranteed permit-review duration for every project type. After submission, the application is routed to the City staff and agencies required for that specific project; approval occurs after all assigned reviewers sign off. Historic review, zoning, corrections, and multi-agency review can add time. Track the specific application rather than relying on generic week-or-month estimates.

The Process

1. Pre-submittal: Confirm the zoning classification of your parcel through the St. Louis Planning & Urban Design Agency at (314) 622-3400. Verify that the proposed use and construction are permitted in the applicable zone.
2. Historic district check: Determine whether the property is in a locally designated historic district or has a historic landmark designation. If so, contact the Cultural Resources Office for pre-application guidance before preparing plans.
3. Plans: Prepare construction documents stamped by a licensed Missouri architect or engineer where required. Residential projects under a certain scope threshold may not require design-professional stamps — confirm with the Building Division.
4. Submit: File the application and construction documents with the Building Division, either online through stlouis-mo.gov or in person. Pay required fees at submission.
5. Plan review: The Building Division reviews plans for compliance with the locally adopted IBC/IRC and St. Louis amendments. Trade disciplines (electrical, plumbing, mechanical) and zoning staff review as applicable.
6. Corrections: Respond to any plan review correction notices and resubmit revised documents. Each correction cycle restarts the review clock for the items in question.
7. Permit issuance: Once plans are approved, pay any remaining fees and receive the issued permit. Post the permit card at the job site before starting construction.
8. Inspections: Schedule required inspections at each construction phase through the Building Division.
9. Final inspection and Certificate of Occupancy: Pass the final inspection to receive a Certificate of Occupancy (C of O) or Certificate of Completion for the work performed.

Inspections

Typical inspection stages for a residential project in the City of St. Louis include:

• Footing and foundation
• Underground plumbing and electrical
• Framing
• Rough plumbing, electrical, and mechanical
• Insulation
• Drywall / lath
• Final building and trade inspections

The permit card must be posted visibly at the job site and approved plans kept on site for all inspections. Work that is covered before the required inspection is approved may require destructive investigation at the contractor's expense.

Schedule inspections through the Building Division at stlouis-mo.gov/government/departments/public-safety/building-division/.

Historic Districts

St. Louis has a significant concentration of historic architecture and numerous locally designated historic districts, including Lafayette Square, Soulard, Compton Heights, and many others. The city's Cultural Resources Office — part of the Planning & Urban Design Agency — reviews proposed alterations to properties within locally designated historic districts.

If your property is in a locally designated historic district:

• Contact the Cultural Resources Office before preparing final plans
• Exterior alterations visible from public rights-of-way are subject to design review
• Replacement materials and methods must be consistent with the Secretary of the Interior's Standards for Rehabilitation
• Some work that would otherwise be over-the-counter may require a Certificate of Appropriateness before a building permit is issued

Properties listed on the National Register of Historic Places but not in a locally designated district are not subject to local historic review for permits, though federal tax credit projects have their own review requirements.

Common Reasons for Denial or Corrections

• Plans do not meet the locally adopted IBC/IRC or St. Louis amendments in the Revised Code
• Missing structural calculations, energy compliance documentation (IECC), or licensed design-professional stamps
• Zoning conflicts (setbacks, height limits, lot coverage, permitted use in the applicable district)
• Missing utility clearances (water, sewer, stormwater connection)
• Cultural Resources Office / historic district review not completed or Certificate of Appropriateness not obtained
• Incomplete submittal — missing drawings, specifications, or application information
• Outstanding violations, stop-work conditions, or other unresolved City holds that affect the application

City vs. County: Getting It Right

Because the City of St. Louis is an independent city, address confusion is common. Here is how to determine which jurisdiction applies:

• City of St. Louis addresses (zip codes such as 63101–63139, 63147, 63155, etc.) — permits from the City of St. Louis Building Division
• St. Louis County municipalities (Chesterfield, Clayton, Webster Groves, Kirkwood, etc.) — each municipality has its own building department
• Unincorporated St. Louis County — permits from St. Louis County Department of Public Works

When in doubt, verify your parcel's jurisdiction through the St. Louis Planning & Urban Design Agency or the city's Citizen Service Bureau.

Official Sources

Always verify current requirements with the City of St. Louis Building Division — Department of Public Safety before starting your project. See the sources in the frontmatter for direct links to the Building Division, the St. Louis Revised Code on Municode, and the Planning & Urban Design Agency.

Disclaimer: This guide summarizes publicly available information from official City of St. Louis sources and is provided for general orientation only. It does not constitute legal or engineering advice. Building code and permitting requirements change — always confirm current rules with the City of St. Louis Building Division, Department of Public Safety, before submitting plans or starting construction. This guide covers the City of St. Louis only and does not apply to St. Louis County or any county municipality.