The City of Saint Charles and St. Charles County share a name and very little else. The county runs its own Building and Code Enforcement Division for unincorporated land, several municipalities inside the county run their own, and the city is only one of them. Getting the name right is not the same as getting the jurisdiction right.
The Building Division administers and enforces the building codes and ordinances adopted by the city, providing field inspections, plan review and permit issuance, with the Department of Community Development responsible for issuing building, electrical, mechanical and plumbing permits.
This guide covers the City of Saint Charles. St. Charles County is a separate authority with its own building division for unincorporated areas, and other municipalities in the county permit independently. A St. Charles address does not settle which of them applies.
The shed threshold has a wire attached to it. Sheds greater than one hundred and forty-four square feet require a permit. Utility sheds under that size do not — but the exemption is written as under one hundred and forty-four square feet without electric, so running power to a small shed pulls it back into permitting. Placement requirements apply either way. Fences follow the same shape: those exceeding six feet in height need a building permit, those under six feet do not.
What requires a building permit in St. Charles?
Missouri has no mandatory statewide building code for private construction. It is a local-option state: whether a building code applies to a parcel at all, and which edition of which model code, depends entirely on what the bodies with authority over that parcel have chosen to adopt. Adoption is done by ordinance incorporating a published code by reference under RSMo section 67.280, and that section defines the bodies that may do it as any county, fire protection district or municipality. So the first question in St. Charles is not which edition applies — it is which body, if any, adopted a code over this parcel.
Typically permit required
- New buildings, additions, and change of occupancy or use
- Structural alterations, load-bearing changes, foundations, decks and retaining walls
- Electrical work under the locally adopted electrical code and the referenced National Electrical Code
- Plumbing and gas work under the locally adopted plumbing code
- Mechanical and HVAC change-outs, and work affecting the energy provisions where any are adopted
- Re-roofing above the exempt scope, pools, signs and demolition
Often exempt
- Ordinary repairs and maintenance replacing materials in kind
- Small accessory structures below the local threshold, where zoning allows
- Painting, flooring, cabinetry and other finish work
- Like-for-like fixture swaps with no alteration to wiring or piping
Exempt lists, thresholds and fee schedules are set by whoever adopted the code, so an exempt list from a neighbouring municipality is not reliable and neither is one from the county. An exemption from a building permit is never an exemption from zoning, floodplain regulation, or an electrical or plumbing permit. Confirm scope with the St. Charles Building Division before work starts.
The three bodies that may hold the code — and the possibility that none does
Three features of Missouri practice catch projects that would be routine elsewhere. First, authority is not guaranteed to exist: a municipality may have adopted a code, the county may have adopted one over unincorporated land, a fire protection district may have adopted a fire code over both, and in parts of the state none of them has adopted anything at all. Second, counties cannot simply decide: section 64.170 empowers county commissions in counties of the first and second classification only, a county building code must be approved at a vote of the voters in the affected area, and incorporated territory is excluded from that vote — which is why so much unincorporated Missouri land has no building code. A county exercising the power appoints a five-member building commission under section 64.180 to prepare the code. Third, even where no code is adopted, design professionals are not unconstrained: the state licensing board’s conduct rules use the 2021 International Building Code as evaluation criteria under section 327.441 where the local jurisdiction has adopted none. Modular units are the one genuinely statewide exception, governed by Public Service Commission rules. New Madrid seismic design applies across the south-east of the state, and tornado wind loading is a live structural constraint throughout. Plan set counts here are prescriptive and differ by work type rather than being a single standard: exterior alterations need four complete sets of plans and site plans with landscape, parking and lighting details plus two sets of structural calculations, interior alterations need three complete sets plus two sets of calculations, and residential needs two complete sets with site plans, truss designs and mechanical drawings — with the truss design carrying an engineer’s seal.
Who handles permitting in St. Charles?
The Building Division safeguards health, safety and welfare through administration and enforcement of the codes and ordinances adopted by the city, providing field inspections, plan review, permit issuance and public services related to new and existing construction.
| Detail | Information |
|---|---|
| Department | City of Saint Charles Building Division, Department of Community Development |
| Address | 200 North Second Street, Suite 303, St. Charles, MO 63301 |
| Phone | (636) 949-3222 |
| Permits issued | Building, electrical, mechanical and plumbing |
| Residential plan sets | Two complete sets with site plans, truss designs and mechanical drawings |
| Exterior alterations | Four complete sets plus two sets of structural calculations |
| Interior alterations | Three complete sets plus two sets of structural calculations |
| Separate authority | St. Charles County Building and Code Enforcement, (636) 949-7345, for unincorporated land |
The permit and no-permit lists are published and worth reading rather than inferring. Permits are generally required for all new residential and commercial construction, decks, additions, solar panels, remodels, patio covers, garages and gazebos, basement finishing, any electrical rewiring or plumbing change, changes in electrical service or a service upgrade, and changes in building use such as converting a residence to a business office.
The exempt list is equally specific: new floor coverings, painting, wallpapering and plastering, replacing a light fixture or faucet, replacing roof shingles and replacing siding. Note that replacing shingles being exempt does not extend to structural roof work, and that the shed exemption is conditioned on there being no electric.
Permit types
Residential permits
Residential submissions need two complete sets of plans with site plans, truss designs and mechanical drawings, and the truss design must carry an engineer’s seal. Setback and placement regulations for sheds and accessory structures come from Planning and Zoning on the same telephone line as the Building Division.
How Missouri contractor credentials work
Missouri issues exactly one construction trade licence at state level, and it is not the one most people expect. There is no state general contractor licence, and no state plumbing, mechanical or HVAC licence — bills to create mechanical licensing have been introduced repeatedly since two thousand eighteen and none has passed. The single exception is the statewide electrical contractor licence under RSMo sections 324.900 to 324.945, administered by the Office of Statewide Electrical Contractors within the Division of Professional Registration, which began issuing licences on the first of July, two thousand nineteen. Everything else is municipal, and in parts of the state no credential is required at all. Architects, professional engineers, land surveyors and landscape architects are separately licensed by their own state board.
The statewide electrical licence overrides local licensing, and the state enforces that hard. Under section 324.925 a political subdivision may keep its own local electrical licence, but it must recognise a statewide licence in lieu of it for performing work and for obtaining permits, and it may not make the holder sit any local proficiency examination. A subdivision that refuses has its local sales tax revenue withheld by the Department of Revenue until it complies. Note the mirror-image rule: a contractor working in a subdivision that requires no local licence at all is not required to hold the statewide licence either.
Outside electrical work, a licence from the next city over may be worth nothing. General, plumbing and mechanical credentials in Missouri are municipal, so they do not travel the way a state licence does. One requirement is statewide, though, and it attaches to the permit application itself: under RSMo section 287.061 every Missouri city and county must obtain proof of workers’ compensation coverage, or a signed exemption affidavit, before issuing. Confirm what the St. Charles Building Division requires for the parcel, confirm the credential is current in this jurisdiction specifically, and confirm insurance independently — in an unlicensed area no public body has checked any of it for you.
Commercial permits
State statutes require a Missouri engineer’s or architect’s seal on all commercial and multi-family plans. Exterior alteration submissions carry the heaviest documentation load, with four complete sets of plans and site plans including landscape, parking and lighting details plus two sets of structural calculations.
Licences, trade classifications and design professionals
Practically, three credential layers appear on Missouri projects, and only one of them is statewide: any municipal contractor licence or registration that applies where you are building; any municipal trade licence for electrical, plumbing or mechanical work; and, on commercial and larger residential work, drawings sealed by a Missouri-licensed architect or professional engineer, whose licence is issued and enforced by the state. Confirm what the St. Charles Building Division requires for the specific building before filing.
St. Charles permit costs and fees
St. Charles fees follow the schedule adopted by the city under its building regulations chapter, with separate provisions for plumbing permit fee exemptions and for waiver of building permit fees in defined circumstances.
| Fee component | How it works |
|---|---|
| Building permit | Set by the adopting jurisdiction, usually on project valuation or square footage; there is no state fee schedule |
| Plan review | A percentage of the permit fee or a flat charge, where the jurisdiction reviews plans at all |
| Trade permits | Separate electrical, plumbing and mechanical fees under the local schedule |
| Municipal licensing | Contractor licence or registration fees where the jurisdiction licenses; nothing where it does not |
| Zoning and use | Zoning, occupancy and, in some places, business licence fees |
| Re-inspections and revisions | Additional fees for failed inspections, revisions and expired permits |
There is no statewide fee schedule in Missouri and no statutory state construction fee, because there is no statewide code to charge against. Every figure is set by the adopting jurisdiction, which means a fee quoted for a project a few miles away may bear no relation to the fee here. Ask the St. Charles Building Division for the schedule in force on your filing date.
Need a real number for a specific St. Charles project? Send us the scope, address and valuation and we will identify which body holds the code for the parcel, the edition it adopted and the fee categories that will apply.
Trade permits and who may pull them
Trade permits are separate from the building permit and, on projects that require one, generally cannot be issued until the building permit is in place. Each trade follows whichever code the city has adopted for it — and because adoption is by part as well as by jurisdiction, a place may have adopted a building code and no plumbing code, or an electrical code and nothing else.
Electrical is the one trade Missouri licenses at state level. The statewide electrical contractor licence is portable and must be recognised by every political subdivision in lieu of a local electrical licence. There is no state plumbing or mechanical licence, so those credentials are municipal and a contractor licensed in one Missouri city may have to qualify again a few miles away. Confirm the permit, the credential that actually applies and the insurance before work starts.
- Electrical work follows the electrical code the jurisdiction adopted and the referenced National Electrical Code, under a statewide electrical contractor licence or an accepted local one.
- Plumbing work follows the adopted plumbing code, under a municipally licensed plumber where the jurisdiction licenses them.
- Mechanical work follows the adopted mechanical and any energy provisions.
Permit required
- Service installations, panel upgrades, new circuits, solar PV and EV chargers
- New plumbing, repipes, water heater change-outs, fixtures, backflow and gas piping
- HVAC installation and change-out, ductwork, venting and commercial kitchen exhaust
- Sprinkler, standpipe and fire alarm work, often under the fire protection district rather than the municipality
Typically exempt
- Replacing a fixture, switch, receptacle or light with no alteration to wiring or piping
- Clearing a stoppage without replacing or rearranging concealed piping
- Filter, thermostat and routine component service
- Like-for-like appliance repair that does not alter the connection
How to apply for a St. Charles building permit
The City of Saint Charles and St. Charles County are separate authorities, and other municipalities in the county permit independently.
Sheds over one hundred and forty-four square feet need a permit, as do sheds under that size with electric, and fences over six feet.
Four sets for exterior alterations, three for interior, two for residential, with structural calculations where required.
Residential submissions require the truss design to carry an engineer's seal.
State statutes require a Missouri engineer's or architect's seal on all commercial and multi-family plans.
Confirm the inspection sequence and notice period with the division, and keep the approved plans on site.
Review, corrections and what actually causes delay
In Missouri the first cause of delay is filing with the wrong body — with the municipality where the parcel is unincorporated, with the county where the county never adopted a code, or with neither where a fire protection district holds the fire code. After that comes the edition question, because the jurisdiction chose its own edition and may be one or two cycles behind the current model code. Then missing local licensing, floodplain requirements along the state’s rivers, and seismic detailing in the south-east. There is no statewide review clock: any timeline you are given is that jurisdiction’s own target, not a statutory obligation. Build the review time into the schedule and confirm the checklist with the St. Charles Building Division before filing.
Approvals do not stay live indefinitely. Permit validity periods are set by the adopting jurisdiction rather than by statute, so they differ from place to place and cannot be assumed from a previous job. On phased or financed work, confirm the expiry window in the local ordinance and keep the permit alive with progress inspections.
Inspections in St. Charles
Where a permit is required, standard checkpoints include footing and foundation, framing, rough-in electrical, plumbing and mechanical, insulation and any adopted energy provisions, fire systems on commercial work, and final, with an occupancy certificate before the building is used. The Building Commissioner and inspectors can be reached directly through the Community Development line for questions arising between inspections.
Missouri inspections are carried out against the edition the jurisdiction adopted and the local amendments it made to it, by inspectors employed or contracted by that jurisdiction. There is no state certification requirement for local building inspectors and no state body auditing them, so practice and interpretation vary more between Missouri jurisdictions than in states with a single code. Keep the approved plans on site for the inspector to check against, and confirm the notice the St. Charles Building Division needs and its inspection windows.
Do not cover work before the required inspection has been approved. Keep the issued permit, the approved plans, product listings and your correction responses available on site.
St. Charles permit search and official resources
Permit records in Missouri sit with the body that issued them, and there is no state repository to fall back on. Where the St. Charles Building Division is the authority for the City of Saint Charles, it holds the building permit, the inspection history and the occupancy certificate. If you are buying, refinancing or renovating, confirm that past work was permitted rather than assuming it was — and in Missouri also confirm whether a permit was ever required, because in some places it was not.
Establish the authority first, then the ordinance, then the edition. Missouri has no statewide code, so all three questions are local and all three have to be answered for the parcel and the filing date before the requirements are knowable. A copy of the adopted code is filed with the clerk of the adopting community and kept available for public inspection.
These are the primary sources behind this guide. Ordinances, fee schedules and procedures change — confirm the position for your filing date.
- City of Saint Charles Building Division
- St. Charles building permit application
- St. Charles Chapter 500, building regulations
- St. Charles County building and construction codes
- Missouri Revisor of Statutes, section 67.280 (adoption by reference)
Frequently asked questions
Do I need a permit for a shed?
Sheds greater than one hundred and forty-four square feet require a permit. Utility sheds under that size do not, but the exemption is written as under one hundred and forty-four square feet without electric, so wiring a small shed brings it back into permitting. Placement and setback requirements apply either way.
What about a fence?
Fences that exceed six feet in height require a building permit. Fences under six feet in height do not, though placement and setback rules still apply. Contact Planning and Zoning for the setback position.
Is the City of Saint Charles the same as St. Charles County?
No. They are separate authorities. The county runs its own Building and Code Enforcement Division for unincorporated land, and several other municipalities inside the county permit independently. Confirm which one holds the parcel before filing.
How many sets of plans do I submit?
It depends on the work. Exterior alterations need four complete sets of plans and site plans with landscape, parking and lighting details plus two sets of structural calculations; interior alterations need three sets plus two sets of calculations; residential needs two complete sets with site plans, truss designs and mechanical drawings.
Does my truss design need a seal?
Yes, on residential submissions the truss design must carry an engineer's seal. On commercial and multi-family work, state statutes require a Missouri engineer's or architect's seal on all plans. Design professionals are state-licensed; the trades mostly are not. Missouri issues exactly one construction trade licence at state level: the statewide electrical contractor licence under RSMo sections 324.900 to 324.945, administered by the Office of Statewide Electrical Contractors and issuing since the first of July, two thousand nineteen. Under section 324.925 every political subdivision must recognise it in lieu of a local electrical licence, and one that refuses has its local sales tax revenue withheld until it complies. There is no state general contractor, plumbing or mechanical licence, so those credentials are municipal. Separately, section 287.061 requires every Missouri city and county to obtain proof of workers compensation cover, or a signed exemption affidavit, before issuing a permit.
Which code edition applies?
The editions the city adopted by reference. Missouri has no mandatory statewide building code for private construction. A code applies to a parcel only because some body adopted one, by ordinance incorporating a published model code by reference under RSMo section 67.280, and that section defines the bodies that may do so as any county, fire protection district or municipality. A copy of the adopted code is filed with the clerk of that community and kept available for public inspection. So the edition, the amendments, the exempt list, the fee schedule and the permit validity period are all local questions, and in some parts of the state the answer is that no code was ever adopted at all.
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- Workers compensation proof and the statewide electrical licence position confirmed before filing
- Correction cycles handled directly with the reviewer, through to the occupancy certificate
Alliance Permitting is a permit documentation and submission company in Missouri. We prepare your paperwork, file it correctly and coordinate with the permitting authority through issuance. We are not a contractor and we do not perform licensed plan review or inspections; that work stays with your licensed team and the jurisdiction.
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More Missouri permitting guides
This guide is provided by Alliance Permitting for general information about St. Charles permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.