County Building Permits
Platte County, MO - 2026 Building Permit Guide
How to apply for a building permit in unincorporated Platte County, Missouri. Permit authority, application steps, fees, and inspection requirements.
Permit Authority
County permitting applies in unincorporated Platte County. Incorporated municipalities generally administer their own local permits unless they explicitly route applicants elsewhere.
- Department
- Platte County Planning and Zoning
- Address
- Platte County Administration Building, 415 Third St., Room 016, Platte City, MO 64079
- Phone
- (816) 858-3338
Online Permit Portal
Platform: GovBuilt county website profile/applications portal • Account required: Yes • Submission: In-person only
Additional resources:
Application Process
- Create or log into a profile on the county website.
- Open My Profile, then Applications, and select the appropriate building permit type.
- Upload all required plans, documents, and project details; permits are reviewed only after required documents are uploaded in full.
- County staff reviews for zoning, building code, and related agency compliance, including floodplain and land disturbance review where triggered.
- Pay fees, obtain issuance, and keep approved plans on site for inspections.
Typical processing time: Not published as a fixed turnaround; inspections require 24 hours advance notice.
General Requirements
The county states permits are processed for new construction, accessory structures, renovations/additions, decks, swimming pools, solar panels, electrical/generator upgrades, mechanical change-outs, demolitions, retaining walls, signs, and commercial projects in unincorporated areas.
Required Documents
- Owner and contractor contact information
- Site plan with setbacks/easements/floodplain
- Plans or drawings
- Valuation
- Signed notarized affidavit
- For commercial work: utility, sewer, fire, and access approvals as applicable
- Building code
- 2018 International Building Code and 2018 International Residential Code; also references National Electrical Code and other locally adopted standards.
- Owner-builder
- Applications may be submitted by owner, lessee, architect, engineer, builder, or agent; property owner name must match the recorded deed on many permit types.
- Contractor requirements
- Public page requires contractor information on applications; no countywide contractor licensing page was located. Confirm trade licensing or registration requirements with Planning and Zoning.
Fees
- Minimum permit fee
- $25 for retaining wall permit; $25 for residential demolition permit; $50 for electrical/mechanical/solar permit; $75 for pool or sign permit
- Plan check fee
- Commercial permits also require payment of the county consulting engineering firm review cost before rough-in inspection.
- Permit fee formula
- Mixed. Examples: deck permit $25 plus $0.10 per square foot over 300 square feet; swimming pool permit $75; fire rebuild permit $100 for first 500 square feet plus $0.05 per additional square foot; commercial building permit $500 for first $5,000 estimated cost plus $25 for each additional $5,000.
- Payment note
- Fee collection occurs after application review and before issuance; some permit types also require refundable bonds or notarized affidavit filings by final inspection.
Fees change. Verify current amounts at the official fee schedule.
Work That Does NOT Require a Permit
- Mechanical like-for-like change-outs when not changing from gas to electric or electric to gas
- Retaining walls 4 feet high or less, measured from bottom of footing to top of wall, when they do not support surcharge and do not have sloped backfill
Important: No broader countywide exempt-work list was posted on the public permit page; confirm with Planning and Zoning before assuming an exemption.
Inspections
How to Schedule
- County portal (online)
- inspection@co.platte.mo.us (email)
- (816) 858-3338 (phone)
- Scheduling deadline
- Inspection requests due 24 hours in advance
- Inspection hours
- Monday through Friday 8:00 am to 5:00 pm
- Time windows
- AM route 9:00 am to 12:00 pm; PM route 2:00 pm to 4:30 pm
Typical inspection sequence: Footing/pier, suspended slab engineer report if applicable, bonding for pools, prebackfill, ground rough, all trades rough-in, gas, final; permit-specific third-party certifications may also be required.
Additional Resources
- Building code: 2018 International Building Code and 2018 International Residential Code; also references National Electrical Code and other locally adopted standards.
- Zoning information: View zoning info
- Building Permit Affidavit
- Platte County Health Department — Sewage Program
- Platte County R-VIII School District
- 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 Platte County Planning and Zoning before applying.
Frequently Asked Questions
Platte County Building Permit FAQ
- Do I need a building permit in unincorporated Platte County, MO?
- The county states permits are processed for new construction, accessory structures, renovations/additions, decks, swimming pools, solar panels, electrical/generator upgrades, mechanical change-outs, demolitions, retaining walls, signs, and commercial projects in unincorporated areas.
- How much does a building permit cost in unincorporated Platte County, MO?
- The minimum permit fee is $25 for retaining wall permit; $25 for residential demolition permit; $50 for electrical/mechanical/solar permit; $75 for pool or sign permit. Fees are calculated as: Mixed. Examples: deck permit $25 plus $0.10 per square foot over 300 square feet; swimming pool permit $75; fire rebuild permit $100 for first 500 square feet plus $0.05 per additional square foot; commercial building permit $500 for first $5,000 estimated cost plus $25 for each additional $5,000.. Plan check fee: Commercial permits also require payment of the county consulting engineering firm review cost before rough-in inspection..
- How do I apply for a building permit in unincorporated Platte County, MO?
- 1. Create or log into a profile on the county website. 2. Open My Profile, then Applications, and select the appropriate building permit type. 3. Upload all required plans, documents, and project details; permits are reviewed only after required documents are uploaded in full. 4. County staff reviews for zoning, building code, and related agency compliance, including floodplain and land disturbance review where triggered. 5. Pay fees, obtain issuance, and keep approved plans on site for inspections.
- How long does it take to get a building permit in unincorporated Platte County, MO?
- Typical processing time is Not published as a fixed turnaround; inspections require 24 hours advance notice..
- What work is exempt from building permits in unincorporated Platte County, MO?
- The following work is generally exempt: Mechanical like-for-like change-outs when not changing from gas to electric or electric to gas; Retaining walls 4 feet high or less, measured from bottom of footing to top of wall, when they do not support surcharge and do not have sloped backfill. Note: No broader countywide exempt-work list was posted on the public permit page; confirm with Planning and Zoning before assuming an exemption.
- How do I schedule a building inspection in unincorporated Platte County, MO?
- Inspections can be scheduled via: County portal, inspection@co.platte.mo.us, (816) 858-3338. Inspection requests due 24 hours in advance.
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