Missouri Plumbing Contractor License

What a Contractor License Requires

The plumbing contractor license is a business-level credential — separate from the individual master plumber trade card. It authorizes a company to advertise plumbing services, hire employees, contract with the public, and pull permits. To get one, the business must designate a licensed master plumber as its full-time qualifying party and satisfy local registration, bonding, and insurance requirements.

Step 1: Register Your Business Entity

Before applying for a contractor license, register your business with the Missouri Secretary of State's Business Portal. Sole proprietorships operating under a name other than the owner's need a Fictitious Name Registration. LLCs and corporations require formal formation filings under RSMo Chapters 347 or 351.

This state registration is a prerequisite everywhere — no municipality will issue a contractor license without it.

Step 2: Get Your Tax IDs

Obtain a state sales tax number from the Missouri Department of Revenue. In Kansas City, Springfield, and St. Louis City, you also need a local Statement of Clearance from the city collector of revenue proving that all local taxes, personal property taxes, and business licenses are fully paid. Some jurisdictions will not issue or renew a contractor license until this clearance is on file.

Step 3: Secure Bonds and Insurance

Surety bonds name the local jurisdiction as obligee. Amounts vary:

Under RSMo § 341.200, bonds must be signed by a licensed corporate surety and approved by the local authority.

General liability insurance minimums range from $500,000 (St. Charles County, St. Louis County) to $1,000,000 (Kansas City, Springfield) per occurrence. Kansas City and Springfield require the city to be named as an additional insured on your certificate.

Workers' compensation is mandatory for any construction firm with one or more employees — stricter than the general five-employee threshold under RSMo Chapter 287. Sole proprietors with no employees must file a notarized exemption with the Division of Workers' Compensation.

Step 4: Apply Locally

Each jurisdiction has its own application portal and fee structure:

• Kansas City: $60 application + $181 issuance via CompassKC
• St. Charles County: $200 biennial ($100 prorated in even years) + $25 new fee via Citizenserve
• Jefferson City: $233 contractor license through the Department of Building Regulations
• Columbia: $30 application + $17 background check + gross receipts license tax
• St. Louis County: Included in business tax registration through the Department of Transportation and Public Works

The Designated Supervisor Rule

The master plumber you name as qualifying party must be a full-time, active employee or owner of the business. They assume personal responsibility for code compliance on every project. A master plumber can qualify only one business entity at a time — if they leave, the company loses its permit authority until a replacement is designated.

Multi-Jurisdiction Operations

Working across city and county lines means holding a separate contractor license in each jurisdiction. That translates to separate bonds where required, separate insurance certificates (potentially naming different entities as additional insured), and separate renewal cycles. A plumber operating in Kansas City, St. Louis County, and St. Charles County maintains three parallel sets of compliance documents.

The Missouri Plumber License Guide includes a contractor setup checklist that sequences these filings in the correct order across seven Missouri jurisdictions.

See more Missouri guides →