Plumbing Contractor Permit Requirements in St. Louis, MO

Complete permit and license guide for starting a plumbing contractor in St. Louis, St. Louis City, Missouri.

Verified 2026-09-02 5 stops $400–$1,200 est. 4–10 weeks to obtain all licenses
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Not legal advice. Requirements may change — always verify with your local government authority before applying. Key agencies and fees on this page were re-checked against official government sources on .

Federal — start here

1 stop

  1. EIN (Employer Identification Number)

    Required if you have employees or operate as an LLC or corporation. Free from the IRS.

    Official government source

    FreeImmediate (online application)

State of Missouri

1 stop

  1. Missouri Department of Revenue — Sales Tax License

    Required for all businesses selling taxable goods in Missouri. The state rate is 4.225%; local rates vary by city and county. Register online with the Missouri Department of Revenue.

    Official government source

    FreeImmediate (online application)

City of St. Louis / St. Louis City

3 stops

  1. Missouri Plumbing Contractor License (local jurisdictions)

    Missouri plumbing licenses are issued at the local level — there is no statewide plumbing license. In St. Louis City, plumbers are licensed through the Board of Examiners for Plumbers and Drainlayers, and a licensed Master Plumber is required for a business to contract plumbing work; Kansas City maintains its own similar licensing.

    Official government source

    Varies by city; confirm exam and license fees with the St. Louis Building Division (Plumbing Section)2–6 weeks

  2. City of St. Louis License Collector — Business License

    St. Louis City is an independent city (not part of St. Louis County) and requires a Graduated Business License (GBL) from the License Collector's Office before commencing business. The license must be renewed annually; renewal applications and payment are due before June 1 to avoid penalties.

    Official government source

    $200 initial fee ($100 if starting between January 1 and May 31); annual renewal is graduated by number of St. Louis employees, from $200 (0-2 employees) up to $37,5001–3 weeks

  3. St. Louis City Plumbing Permit (per project)

    A plumbing permit must be pulled for each job. Permits are issued only to plumbing contractors holding a Plumbing Contractor license from the City of St. Louis Building Division. Rough and finish inspections are both required.

    Official government source

    $30 application fee, plus $25 rough inspection, $25 finish inspection, $10 per fixture/roof drain/trapped outlet, $25 per water tap or connection, and $25 per sewer extension, connection or repair (City Ordinance 71644). Re-inspection $30.Most applications approved in 1-3 business days; up to 10 business days

Terminus

Open for business — est. $400–$1,200 · 4–10 weeks to obtain all licenses

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