On this page 6
§ 02
When a permit is required
Permit triggers and exempt work for Platte County
County pages state permits are processed for new construction, accessory structures, renovations, additions, decks, pools, solar panels, electrical and mechanical change-outs, demolitions, retaining walls, signs, and commercial projects in unincorporated areas
Mechanical like-for-like change-outs are stated as exempt 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, are exempt only when they do not support surcharge and do not have sloped backfill
No broader countywide exempt-work list was posted on the public permit page
- Exempt Mechanical like-for-like change-outs are stated as exempt when not changing from gas to electric or electric to gas
- Exempt Retaining walls 4 feet high or less, measured from bottom of footing to top of wall, are exempt only when they do not support surcharge and do not have sloped backfill
- Exempt No broader countywide exempt-work list was posted on the public permit page
Required documents
- When a permit is required: County pages state permits are processed for new construction, accessory structures, renovations, additions, decks, pools, solar panels, electrical and mechanical change-outs, demolitions, retaining walls, signs, and commercial projects in unincorporated areas
- Required documents: Common requirements include owner and contractor information, site plan with setbacks and easements, plans or drawings, valuation, and a signed notarized affidavit. Commercial work may need utility, sewer, fire, and access approvals
- Permit validity/expiration: Not clearly published on the main county permit page
- Owner-builder rules if available: 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 license requirements: Public page requires contractor information on applications; no countywide contractor licensing page was located
- Building code adopted: The county permit page references the 2018 International Building Code and 2018 International Residential Code
- Building code
- The county permit page references the 2018 International Building Code and 2018 International Residential Code
- Permit validity
- Not clearly published on the main county permit page
- 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
§ 03
Application process
Typical processing: Not published as a fixed turnaround; inspections require 24 hours advance notice
- 01 Create or log into a profile on the county website
- 02 Open My Profile, then Applications, and select the appropriate permit type
- 03 Upload required plans, documents, and project details
- 04 County staff reviews zoning, building code, and companion reviews such as floodplain or land disturbance when triggered
- 05 Pay fees and obtain permit issuance
- 06 Keep approved documents available for inspections
Typical processing time: Not published as a fixed turnaround; inspections require 24 hours advance notice
§ 04
Fee schedule
Platte County building permit fees
Fee type
Amount
01
Minimum permit fee
$25 retaining wall permit; $25 residential demolition permit; $50 electrical, mechanical, or solar permit; $75 pool or sign permit
02
Plan check fee
Commercial permits also require payment of the county consulting engineering firm review cost before rough-in inspection
03
Permit fee formula
Mixed. Examples published by the county include 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, and commercial building permit $500 for first $5,000 estimated cost plus $25 for each additional $5,000
04
Reinspection fee
Not separately published on the main public permit page
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 periodically. Confirm at the official fee schedule ↗ before budgeting.
§ 05
Required inspections
Scheduling and sequence
How to schedule
- Online portal account, email to inspection@co.platte.mo.us, or phone at (816) 858-3338 ()
- Inspection hours
- Monday through Friday 8:00 am to 5:00 pm; inspection requests due 24 hours in advance; AM route 9:00 am to 12:00 pm and PM route 2:00 pm to 4:30 pm
Typical sequence: Footing or pier, suspended slab engineer report if applicable, bonding for pools, prebackfill, ground rough, all trades rough-in, gas, final
§ 06
Frequently asked
Common questions about unincorporated Platte County permits
01 Do I need a building permit in unincorporated Platte County, MO? ▸
County pages state permits are processed for new construction, accessory structures, renovations, additions, decks, pools, solar panels, electrical and mechanical change-outs, demolitions, retaining walls, signs, and commercial projects in unincorporated areas
02 How much does a building permit cost in unincorporated Platte County, MO? ▸
Building permit fees in unincorporated Platte County, MO are set by the local building department and vary by project type and valuation. The minimum permit fee is $25 retaining wall permit; $25 residential demolition permit; $50 electrical, mechanical, or solar permit; $75 pool or sign permit. Fees are calculated as: Mixed. Examples published by the county include 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, and 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.
03 How do I apply for a building permit in unincorporated Platte County, MO? ▸
To apply for a building permit in unincorporated Platte County, MO, follow these steps: 1. Create or log into a profile on the county website 2. Open My Profile, then Applications, and select the appropriate permit type 3. Upload required plans, documents, and project details 4. County staff reviews zoning, building code, and companion reviews such as floodplain or land disturbance when triggered 5. Pay fees and obtain permit issuance 6. Keep approved documents available for inspections
04 How long does it take to get a building permit in unincorporated Platte County, MO? ▸
Building permit processing times in unincorporated Platte County, MO typically run Not published as a fixed turnaround; inspections require 24 hours advance notice. Timelines can vary based on project complexity and current department workload.
05 What work is exempt from building permits in unincorporated Platte County, MO? ▸
Not all construction work requires a permit in unincorporated Platte County, MO. The following work is generally exempt: Mechanical like-for-like change-outs are stated as exempt 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, are exempt only when they do not support surcharge and do not have sloped backfill; No broader countywide exempt-work list was posted on the public permit page. When in doubt, confirm with the local building department before starting work.
06 How do I schedule a building inspection in unincorporated Platte County, MO? ▸
Once your permit is issued and work reaches an inspection milestone, you can schedule a building inspection in unincorporated Platte County, MO via: Online portal account, email to inspection@co.platte.mo.us, or phone at (816) 858-3338.
last verified April 2026
source Platte County Planning and Zoning ↗
entry id permits/missouri/platte/unincorporated
Educational reference. Permit rules and fees change — confirm current requirements directly with Platte County Planning and Zoning before applying. Jaspector is not legal advice.