How much does a building permit cost in unincorporated Miami County, OH?

The minimum permit fee is Residential fees start at 100 dollars class by class, with many base permits at 150 to 300 dollars depending on scope. Commercial fees start with a 302.50 dollar processing fee for several categories.. Fees are calculated as: Residential fees are square-foot and permit-type based. Commercial fees use processing fees plus square-foot rates, plus special category flat fees.. Plan check fee: Commercial plan review is 140 dollars per hour. Residential plan review is included in the fee schedule categories shown on the county fee PDF..

What work is exempt from building permits in unincorporated Miami County, OH?

The following work is generally exempt: General maintenance and repair; Roof repair or replacement on a structure under 200 square feet; Telephone communication utility installation; County roof policy says non-structural tear-off and re-roof work does not require a permit, but structural repairs do.

How do I schedule a building inspection in unincorporated Miami County, OH?

Inspections can be scheduled via: Phone the office at 937-440-8121. The county inspection request webpage says the online request link is disabled..

County Building Permits

Miami County, OH - 2026 Building Permit Guide

How to apply for a building permit in unincorporated Miami County, Ohio. Permit authority, application steps, fees, and inspection requirements.

Ohio Updated March 2026

Permit Authority

Unincorporated Miami County and the county building-permit jurisdictions shown on the county map

Department: Miami County Department of Development, Building Regulations
Address: 1506 One Stop Court, Suite 6, Troy, OH 45373
Phone: 937-440-8121
Email: Rob England email link is published on the county page , but the visible page text does not expose the address directly
Website: https://www.co.miami.oh.us/137/Building-Regulations

Online Permit Portal

Open

Platform: iWorQ Online Customer Portal • Account required: Yes • Submission: In-person only

Application Process

Confirm permit need using the county PDF and current code pages.
Prepare plans and required documentation as one multipage PDF for residential submittals.
Submit through the iWorQ portal.
County staff review the application and plans.
Pay fees and obtain permit pickup or issuance notification.
Schedule inspections by phone because the online inspection request link is temporarily disabled on the county page.

General Requirements

Required Documents

County residential or commercial application, plans, and code compliance material. Residential submittals must be one multipage PDF and one contact for the project.

Building code: County page links current building codes and says Miami County enforces the commercial and residential building codes. County page also references 2024 Ohio code changes effective March 1, 2024.
Contractor requirements: County page does not show a separate county general contractor license, but state OCILB trade licensing still applies for electrical, plumbing, and HVAC work.

Fees

Minimum permit fee: Residential fees start at 100 dollars class by class, with many base permits at 150 to 300 dollars depending on scope. Commercial fees start with a 302.50 dollar processing fee for several categories.
Plan check fee: Commercial plan review is 140 dollars per hour. Residential plan review is included in the fee schedule categories shown on the county fee PDF.
Permit fee formula: Residential fees are square-foot and permit-type based. Commercial fees use processing fees plus square-foot rates, plus special category flat fees.

Fees change. Verify current amounts at the official fee schedule.

Work That Does NOT Require a Permit

General maintenance and repair
Roof repair or replacement on a structure under 200 square feet
Telephone communication utility installation
County roof policy says non-structural tear-off and re-roof work does not require a permit, but structural repairs do

Inspections

How to Schedule

Phone the office at 937-440-8121. The county inspection request webpage says the online request link is disabled. (online)

Typical inspection sequence: County provides a required inspection list for each project after permit review

Residential re-inspection fee is 150 dollars. Commercial re-inspection fee is 165 dollars plus the state assessment fee

Additional Resources

Building code: County page links current building codes and says Miami County enforces the commercial and residential building codes. County page also references 2024 Ohio code changes effective March 1, 2024.
Other links
Other links
Other links
License lookup guide: Ohio Contractor License Requirements
Contract template: Ohio Homeowner-Contractor Agreement
Ohio hub: Ohio Contractor License & Permit Hub

Information on this page was last verified: March 2026. Permit rules and fees change — confirm current requirements directly with the Miami County Department of Development, Building Regulations before applying.

Frequently Asked Questions

Miami County Building Permit FAQ

How much does a building permit cost in unincorporated Miami County, OH?: The minimum permit fee is Residential fees start at 100 dollars class by class, with many base permits at 150 to 300 dollars depending on scope. Commercial fees start with a 302.50 dollar processing fee for several categories.. Fees are calculated as: Residential fees are square-foot and permit-type based. Commercial fees use processing fees plus square-foot rates, plus special category flat fees.. Plan check fee: Commercial plan review is 140 dollars per hour. Residential plan review is included in the fee schedule categories shown on the county fee PDF..
How do I apply for a building permit in unincorporated Miami County, OH?: 1. Confirm permit need using the county PDF and current code pages. 2. Prepare plans and required documentation as one multipage PDF for residential submittals. 3. Submit through the iWorQ portal. 4. County staff review the application and plans. 5. Pay fees and obtain permit pickup or issuance notification. 6. Schedule inspections by phone because the online inspection request link is temporarily disabled on the county page.
What work is exempt from building permits in unincorporated Miami County, OH?: The following work is generally exempt: General maintenance and repair; Roof repair or replacement on a structure under 200 square feet; Telephone communication utility installation; County roof policy says non-structural tear-off and re-roof work does not require a permit, but structural repairs do.
How do I schedule a building inspection in unincorporated Miami County, OH?: Inspections can be scheduled via: Phone the office at 937-440-8121. The county inspection request webpage says the online request link is disabled..

Need help with your project?

Navigating permits in Unincorporated Miami County can be complicated.

Jaspector connects you with local experts who can review your scope, verify your contractor, and help you understand what permits your project actually needs.

Learn how Jaspector works

Important: 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.

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