Plumbing Contractor Permit Requirements in Louisville, KY

1. EIN (Employer Identification Number)

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

   Official government source

   Free·Immediate (online application)

   Free

   Immediate (online application)

1. Kentucky Department of Revenue — Sales and Use Tax Permit (Retailer's or Seller's Permit)

   KRS 139.200 imposes a 6% tax on the gross receipts of all retailers from retail sales of tangible personal property and of digital property, and from the furnishing of the services enumerated in subsection (2). That enumerated list is long and catches many service businesses that assume they are untaxed: landscaping services including lawn care and maintenance, tree trimming, landscape design and installation, and snow plowing or removal (paragraph (g)); janitorial services including residential and commercial cleaning and carpet, upholstery and window cleaning (h); small animal veterinary services (i); pet care services including grooming, boarding, pet sitting and obedience training (j); non-coin-operated laundry and dry cleaning (l); indoor skin tanning (n); non-medical diet and weight reducing (o); extended warranty services (p); photography and photofinishing (q); telemarketing (r); lobbying (t); executive employee recruitment (u); website design and development (v) and website hosting (w); bodyguard services (z); security system monitoring (aa); private investigation (ab); process serving (ac); repossession (ad); personal background checks (ae); parking and valet (af); rental of space for meetings, conventions, weddings, banquets, parties and other short-term social events (ai); social event planning and coordination (aj); leisure, recreational and athletic instructional services (ak); recreational camp tuition (al); personal fitness training (am); massage except when medically necessary (an); cosmetic surgery (ao); body modification including tattooing, piercing, scarification and branding (ap); non-medical laboratory testing (aq); interior decorating and design (ar); household moving (as); specialized design (at); lapidary (au); labor to repair or maintain commercial refrigeration equipment where no property is sold (av); labor to repair or alter apparel, footwear, watches or jewelry where no property is sold (aw); prewritten computer software access services (ax); and data brokering services (ay), the last effective August 1, 2026. KRS 139.240(1) requires every person presently engaged in or desiring to engage in business as a retailer or seller in Kentucky to file a permit application for each place of business, and KRS 139.250 requires the department to issue a separate permit per location, makes it nonassignable, limits it to the person named, and requires it to be conspicuously displayed. There are no local sales and use taxes in Kentucky, so the rate is 6% statewide.

   Official government source

   No fee. Neither KRS 139.240 nor KRS 139.250 prescribes a charge for the retailer's or seller's permit, and the Department of Revenue issues the account at no cost through the Kentucky Business One Stop registration·Not published by the Department of Revenue. KRS 139.240(1) requires the application to be on file before engaging in business as a retailer, and KRS 139.240(4) waives the written signature for electronic registrants, so file through the Kentucky Business One Stop before the first taxable sale

   No fee. Neither KRS 139.240 nor KRS 139.250 prescribes a charge for the retailer's or seller's permit, and the Department of Revenue issues the account at no cost through the Kentucky Business One Stop registration

   Not published by the Department of Revenue. KRS 139.240(1) requires the application to be on file before engaging in business as a retailer, and KRS 139.240(4) waives the written signature for electronic registrants, so file through the Kentucky Business One Stop before the first taxable sale

1. Kentucky DHBC Division of Plumbing — Master Plumber License

   Plumbing contractors in Kentucky must hold a master plumber licence issued by the Division of Plumbing within the Department of Housing, Buildings and Construction, (502) 573-0365. Under 815 KAR 20:030 an applicant qualifies by holding a valid Kentucky journeyman plumber licence for at least two of the past five years while working under a licensed master plumber — not four years — or alternatively by holding a Kentucky engineer licence with sufficient mechanical engineering experience, by holding another state's plumbing licence for two of the past five years, or by four consecutive years of equivalent practice in a state that issues no plumbing licence. The applicant must pass the Kentucky master plumber examination with at least 80 percent on each portion, and a master plumber must carry the insurance required by KRS 318.030. Licences expire on the last day of the licensee's birth month and require continuing education under 815 KAR 2:010 to renew.

   Official government source

   $150 master plumber examination fee (charged again for any retake) and a $250 initial licence fee, which may be prorated for 7 to 18 months. Renewal is $250; inactive status costs $125 and reactivation $125. Plumbing installation permits are separate: $50 base plus $14 per opening for one- and two-family residential work, or $50 plus $20 per opening for other buildings·Not published by the Division of Plumbing. Master plumber examinations are held in February, May, August and November, a passing score stays valid three years, and an application that is not completed within one year is void

   $150 master plumber examination fee (charged again for any retake) and a $250 initial licence fee, which may be prorated for 7 to 18 months. Renewal is $250; inactive status costs $125 and reactivation $125. Plumbing installation permits are separate: $50 base plus $14 per opening for one- and two-family residential work, or $50 plus $20 per opening for other buildings

   Not published by the Division of Plumbing. Master plumber examinations are held in February, May, August and November, a passing score stays valid three years, and an application that is not completed within one year is void

2. Louisville Metro Revenue Commission — Occupational License Tax Registration

   Louisville Metro does not issue a general local business license. The Louisville Metro Revenue Commission states that to start a new business "there is no local business license required"; instead a new business must register with the Revenue Commission, the Jefferson County Clerk's Office, and the Commonwealth of Kentucky. Registration with the Revenue Commission opens an occupational license tax account. The tax is on net profits (and on employee wages, withheld quarterly on Form W-1), reported annually on Form OL-3, due the 15th day of the 4th month after the end of the taxpayer's fiscal year. There is no flat annual license fee. The claim's Develop Louisville URL is the wrong agency; the Revenue Commission administers this registration.

   Official government source

   No local business license fee. Occupational license tax of 2.2% (resident rate) or 1.45% (non-resident rate) on net profits and on wages; minimum $25 penalty for filing late·Not published by the Revenue Commission; registration is completed online. The annual OL-3 return is due the 15th day of the 4th month after the fiscal year ends

   No local business license fee. Occupational license tax of 2.2% (resident rate) or 1.45% (non-resident rate) on net profits and on wages; minimum $25 penalty for filing late

   Not published by the Revenue Commission; registration is completed online. The annual OL-3 return is due the 15th day of the 4th month after the fiscal year ends

3. Kentucky Division of Plumbing — Plumbing Construction Permit (per job)

   Plumbing permits in Louisville come from the Division of Plumbing within the Kentucky Department of Housing, Buildings and Construction, not from Louisville Metro: the city's promulgated construction fee schedule under LMCO 150.096 covers building, electrical, HVAC, fire detection, moving, wrecking, sign, and parking lot permits and contains no plumbing category. No person or firm may construct, install, or alter plumbing without first obtaining a plumbing construction permit, which is issued to a licensed master plumber (or to a homeowner for their own residence), and a state plumbing inspection is required on completion.

   Official government source

   One- and two-family residential: $50 base plus $14 per opening. Domestic water heater only: $50. Commercial and medical gas piping: $50 base plus $20 per opening (schedule effective March 1, 2022)·Permits are obtained online through the Division of Plumbing's permit system; no processing time is published

   One- and two-family residential: $50 base plus $14 per opening. Domestic water heater only: $50. Commercial and medical gas piping: $50 base plus $20 per opening (schedule effective March 1, 2022)

   Permits are obtained online through the Division of Plumbing's permit system; no processing time is published

Official Sources

• Kentucky Division of Plumbing — Master Plumber License
• Louisville Metro Revenue Commission

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