County Building Permits
Jefferson County, MO - 2026 Building Permit Guide
How to apply for a building permit in unincorporated Jefferson County, Missouri. Permit authority, application steps, fees, and inspection requirements.
Missouri Updated March 2026
Permit Authority
Unincorporated Jefferson County. Incorporated municipalities route permit work through their own city or village government unless they expressly contract that work elsewhere.
- Department
- Jefferson County Code Enforcement Division
- Address
- 725 Maple Street, Hillsboro, MO 63050
- Phone
- 636-797-5310
Online Permit Portal
Platform: CivicGov • Account required: Yes • Submission: In-person only
Additional resources:
Application Process
- Confirm the parcel is in unincorporated Jefferson County and identify whether Code Enforcement, Planning, Highway/Stormwater, floodplain, or sewage review applies.
- For zoning and land-use filings, use the Citizen Portal and schedule any required pre-application conference with Planning at 636-797-5580.
- Submit permit and plan materials to the applicable county division, including any deed or proof-of-ownership and checklist items required by Planning.
- Pay plan review and permit fees under the county fee ordinance.
- Receive permit approval before work starts and coordinate inspections as work progresses.
General Requirements
County FAQ states permits are required for many building, structural, trade, and safety-related projects in unincorporated Jefferson County.
Required Documents
- Permit-specific plans
- Proof of ownership for Planning filings
- Site plan and checklist materials where zoning, CUP, variance, deviation, or plat review applies
- Building code
- Jefferson County Building Code fee ordinance and county code provisions; county FAQ exemption language tracks IRC-style thresholds. Planning and floodplain controls also apply where relevant.
- Contractor requirements
- County permit page separately lists contractor licenses.
Fees
- Minimum permit fee
- Residential building and each revision submittal $40.00 plan review; commercial building submittal $200.00; processing fee $25.00
- Plan check fee
- Residential submittal $40.00; commercial submittal $200.00; sewage submittal $40.00
- Permit fee formula
- Valuation-based and square-foot-based building permit fee tables under Ordinance 21-0356
- Reinspection fee
- Inspection or re-inspection fee $50.00
- Payment note
- Plan review and submittal fees are paid upon application and deducted from total fee.
Fees change. Verify current amounts at the official fee schedule.
Work That Does NOT Require a Permit
- Decks not exceeding 200 square feet, not over 30 inches above grade, not attached to a dwelling, and not serving the required exit door
- Fences not over 8 feet high
- Gas or electric hot water heater replacement
- One-story detached accessory structures not over 200 square feet
- Painting, papering, tiling, carpeting, cabinets, countertops, and similar finish work
- Prefabricated swimming pools less than 24 inches deep
- Retaining walls not over 6 feet high unless supporting a surcharge
- Sidewalks and driveways not more than 30 inches above adjacent grade and not over a basement or story below
- Swings and playground equipment accessory to a one- or two-family dwelling
- Certain tanks, awnings, minor repairs, and emergency repairs filed the next business day where applicable
Inspections
How to Schedule
- Code Enforcement Division (in-person)
Typical inspection sequence: Permit issuance, trade or structural inspections during work, then final approval; actual sequence varies by project and whether zoning, floodplain, sewage, or stormwater review applies.
Additional Resources
- Building code: Jefferson County Building Code fee ordinance and county code provisions; county FAQ exemption language tracks IRC-style thresholds. Planning and floodplain controls also apply where relevant.
- Zoning information: View zoning info
- FAQ
- GIS Maps
- 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 Jefferson County Code Enforcement Division before applying.
Frequently Asked Questions
Jefferson County Building Permit FAQ
- Do I need a building permit in unincorporated Jefferson County, MO?
- County FAQ states permits are required for many building, structural, trade, and safety-related projects in unincorporated Jefferson County.
- How much does a building permit cost in unincorporated Jefferson County, MO?
- The minimum permit fee is Residential building and each revision submittal $40.00 plan review; commercial building submittal $200.00; processing fee $25.00. Fees are calculated as: Valuation-based and square-foot-based building permit fee tables under Ordinance 21-0356. Plan check fee: Residential submittal $40.00; commercial submittal $200.00; sewage submittal $40.00.
- How do I apply for a building permit in unincorporated Jefferson County, MO?
- 1. Confirm the parcel is in unincorporated Jefferson County and identify whether Code Enforcement, Planning, Highway/Stormwater, floodplain, or sewage review applies. 2. For zoning and land-use filings, use the Citizen Portal and schedule any required pre-application conference with Planning at 636-797-5580. 3. Submit permit and plan materials to the applicable county division, including any deed or proof-of-ownership and checklist items required by Planning. 4. Pay plan review and permit fees under the county fee ordinance. 5. Receive permit approval before work starts and coordinate inspections as work progresses.
- What work is exempt from building permits in unincorporated Jefferson County, MO?
- The following work is generally exempt: Decks not exceeding 200 square feet, not over 30 inches above grade, not attached to a dwelling, and not serving the required exit door; Fences not over 8 feet high; Gas or electric hot water heater replacement; One-story detached accessory structures not over 200 square feet; Painting, papering, tiling, carpeting, cabinets, countertops, and similar finish work; Prefabricated swimming pools less than 24 inches deep; Retaining walls not over 6 feet high unless supporting a surcharge; Sidewalks and driveways not more than 30 inches above adjacent grade and not over a basement or story below; Swings and playground equipment accessory to a one- or two-family dwelling; Certain tanks, awnings, minor repairs, and emergency repairs filed the next business day where applicable.
- How do I schedule a building inspection in unincorporated Jefferson County, MO?
- Inspections can be scheduled via: Code Enforcement Division.
Need help with your project?
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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.