How to Start a Plumbing Business in Louisiana

Starting a plumbing business in Louisiana requires more than a truck and a toolbox. You need a license from the State Plumbing Board, a contractor classification from the Louisiana State Licensing Board for Contractors (LSLBC), a registered business entity, and compliance with parish-level occupational taxes and sales registration. This guide walks you through the steps in order, with the specific fees and requirements that apply in 2026.

Understand Louisiana Plumbing License Requirements

Louisiana has two main levels of plumbing license issued by the State Plumbing Board, which is part of the Louisiana State Licensing Board for Contractors. Before you can legally do plumbing work or form a plumbing business, you need to meet the qualifications for one of these.

Journeyman Plumber License

A journeyman plumber license is the entry-level professional credential. To qualify, you must meet the following requirements:

• Five years of practical experience in plumbing work under a licensed master or journeyman plumber. The LSLBC measures this as approximately 8,000 hours of on-the-job training.
• Pass the Louisiana journeyman plumber examination administered by the State Plumbing Board.
• Apply through the Louisiana State Licensing Board for Contractors (LSLBC) licensing portal.

The specific application fees, exam costs, and renewal amounts are set by the LSLBC. Confirm the current fees and application timeline directly with the LSLBC before you apply, as these figures change periodically. The LSLBC website is your source for the official fee schedule and exam dates.

Master Plumber License

A master plumber license allows you to own and operate a plumbing business, supervise other plumbers, and sign off on plumbing work. To qualify as a master plumber in Louisiana, you typically need:

• A valid journeyman plumber license.
• An additional one to five years of experience as a licensed journeyman (the LSLBC specifies the exact duration and hours).
• A passing score on the Louisiana master plumber examination.
• Proof of financial responsibility or bonding, as required by the board.

As a master plumber, you can then apply for the LSLBC plumbing contractor license, which is required to legally bid and perform plumbing projects in Louisiana.

Gas Fitter License and Water Supply Protection Specialist Endorsement

If you plan to install or repair gas lines or water supply systems, Louisiana may require additional endorsements or separate licenses:

• Gas Fitter License: Allows you to work on gas piping and appliance connections. Verify current requirements with the State Plumbing Board.
• Water Supply Protection Specialist: This endorsement may be required if you work on water quality, backflow prevention, or specialized water-system components. Confirm requirements with the LSLBC.

These endorsements have their own application processes and fees. Contact the State Plumbing Board of Louisiana directly to verify which endorsements apply to your specific service offerings and to confirm the current requirements and costs.

Choose Your Business Structure

Before you file with the Louisiana Secretary of State, decide whether to form an LLC or a corporation. Both are common for plumbing businesses.

LLC (Limited Liability Company): Offers personal liability protection, simpler tax reporting, and lower upfront costs. The Louisiana Secretary of State filing fee is $125 as of October 1, 2026. Annual reports cost $35 per year and are due on your anniversary date of formation.

Corporation: Also provides liability protection but involves more formal record-keeping and a standard $95 filing fee with the Secretary of State, plus $35 annual reports. Corporations must follow more rigid operational rules.

Most plumbing business owners choose an LLC for its simplicity and flexibility, but consult a Louisiana accountant or attorney to determine which structure makes sense for your specific situation.

Reserve Your Business Name

Before you file, make sure your business name is available. Search the Louisiana Secretary of State's business entity database at https://coraweb.sos.la.gov/CommercialSearch/CommercialSearch.aspx to confirm no one else is using the name you want.

You can also reserve a name for 120 days by filing a reservation form with the Secretary of State for a $25 fee. This gives you time to complete your licensing and other startup steps without worrying that the name will be taken.

Your business name must include "LLC" or "Limited Liability Company" if you are forming an LLC, and it must be distinguishable from other registered businesses in Louisiana. Names are checked by exact spelling, alternate spellings, and phonetic similarity, so a name that sounds the same may be rejected.

File Your Business Formation Documents with geauxBIZ

Louisiana's one-stop business filing portal is called geauxBIZ. You access it at https://geauxbiz.sos.la.gov/. Here's what you'll do:

1. Create an account on the geauxBIZ portal.
2. File your Articles of Organization (for an LLC) or Articles of Incorporation (for a corporation). Include your business name, registered agent name and Louisiana street address, principal place of business, and member or shareholder information.
3. Pay the filing fee. For an LLC, this is $125. For a corporation, it is $95. Payment is due at the time of filing.
4. Submit the form electronically through geauxBIZ.

Standard processing times are not published by the Secretary of State. However, you can pay an expedite fee to speed up processing: $30 for next-business-day processing or $50 for same-day processing while you wait at the Baton Rouge office.

Once approved, you'll receive a certified copy of your formation document. Keep this safe, along with your EIN documentation and any other official licenses, because you'll need them to open a bank account and apply for the next set of registrations.

Get Your Federal Employer Identification Number (EIN)

An EIN is a nine-digit tax ID number issued by the Internal Revenue Service. You'll use it for business banking, hiring employees, and tax filing. You can apply for an EIN free of charge through the IRS at https://www.irs.gov/ein. Most applications are approved within a few minutes if you apply online.

Register with the LSLBC for Plumbing Contractor Classification

This is the critical step that allows you to bid and perform plumbing work in Louisiana. The LSLBC requires a plumbing contractor license if your plumbing work is estimated at $10,000 or more.

To qualify, you must:

• Hold a valid master plumber license from the State Plumbing Board.
• Satisfy the LSLBC's experience, exam, and financial-responsibility requirements for contractor classification.
• Pay the LSLBC application and licensing fees. The exact amounts are set by the LSLBC. Confirm current fees before applying.
• Obtain a surety bond as required by the LSLBC (amounts vary by contract size and project type).

Verify all LSLBC plumbing contractor requirements, fees, and the application process at the LSLBC office or website. Missing or incorrect information will delay your approval.

If your plumbing work is under $10,000, you may not need LSLBC classification, but check local municipal requirements, as some jurisdictions have their own thresholds and licensing rules.

Register for Sales Tax and Get Your Sales Tax Permit

Louisiana charges a 5% state sales tax, and most parishes add a local sales tax on top of that. You must register with your parish sales-tax collector and with the Louisiana Department of Revenue.

1. Determine your parish collector. Each Louisiana parish has a single official sales-tax collector, typically the sheriff's office, school board, or a dedicated tax office. Search online for "[Parish Name] sales tax collector" to find the correct office.
2. Register with the LDR (Louisiana Department of Revenue). You can register online at https://revenue.louisiana.gov/businesses/general-resources/business-registration/. You'll need your EIN, business name, and registration address.
3. Register with your parish collector. Your parish collector maintains a separate registration. Louisiana does not have a combined state-and-local sales-tax account; each has its own process. Contact your parish collector's office for forms and deadlines.

Once registered, you'll receive a sales tax permit or certificate. Some parishes allow optional combined filing, so ask whether your parish offers that option.

File a DBA (Doing Business As) with Your Parish Clerk

Louisiana law requires you to file an assumed-name certificate (DBA) with the clerk of court in every parish where you operate. This is mandatory, regardless of your business entity type. The filing must be notarized, and you'll pay a clerk fee (which varies by parish, typically $50 to $200). File this through your local parish clerk of court, not the Secretary of State.

Obtain Your Parish Occupational License

Most Louisiana parishes and municipalities levy an occupational license tax on plumbing businesses. This is a local fee, not a state license, and amounts vary widely by jurisdiction. Some parishes have no occupational tax at all.

• Contact your parish assessor's office or the city revenue office for your local jurisdiction to learn the fee and application process.
• Bring your LSLBC contractor license and EIN confirmation.
• Pay the occupational license tax and file any required forms.

This is a separate filing from your sales tax registration, so don't skip it. Operating without an occupational license can result in fines.

Get Business Insurance and Bonding

Liability and workers' compensation insurance are not optional if you want to stay in business. Customers and municipalities will require proof of insurance before you can perform work.

• General Liability Insurance: Protects you if a customer is injured or their property is damaged due to your work. Expect to pay $500 to $2,000 annually depending on your coverage limits and claims history.
• Workers' Compensation Insurance: Required by Louisiana law if you have even one employee. Contact the Office of Workers' Compensation Administration (now part of the Louisiana Workforce Commission) for rates and insurers.
• Bonding: The LSLBC may require a contractor bond. Your surety bond protects customers if you fail to complete a job or perform shoddy work. Bond costs are typically 1% to 3% of the bond amount.

Shop around with commercial insurance brokers familiar with plumbing contractors to get competitive quotes.

Open a Business Bank Account

Separate your personal and business finances from day one. When you visit your bank, bring:

• Your EIN confirmation letter from the IRS.
• Your Articles of Organization or Incorporation (certified copy from the Secretary of State).
• Your business license or LSLBC contractor license.
• Your personal ID.

Opening a business account typically takes a few business days, and many banks waive monthly fees for small-business accounts.

Tips and Common Mistakes to Avoid

Don't Confuse State and Local Filings

New business owners often miss the parish occupational license, DBA filing, or local sales tax registration because they think the Secretary of State filing covers everything. It doesn't. Louisiana requires multiple filings:

• Secretary of State: entity formation (LLC or corporation)
• LSLBC: plumbing contractor license
• State Plumbing Board: journeyman and master licenses
• LDR: state sales tax registration
• Parish collector: local sales tax registration
• Parish clerk: DBA / assumed name
• Parish assessor or city revenue: occupational license

Missing any one of these can result in fines, the inability to bid jobs, or legal liability.

Verify Fees Before You File

Licensing fees change regularly. Before you pay, confirm the current amounts with the LSLBC, State Plumbing Board, and your parish clerk. Don't assume fees from this article are current; check the official source.

Get Your Master License First

You cannot apply for an LSLBC plumbing contractor license without a valid master plumber license from the State Plumbing Board. Build your experience and pass the licensing exams before you invest in the business formation.

Don't Operate Without Insurance

It's tempting to skip insurance to save money, but a single claim or injury can bankrupt your business. General liability and workers' compensation are standard requirements and reasonable costs of doing business.

Track All Filing Dates

Your annual reports are due on the anniversary of your formation date every year. Your occupational license may require renewal. Your LSLBC contractor license has its own renewal date. Set reminders for all of these so you don't lose your licenses or owe late fees.

Disclaimer

This article is informational and not a substitute for legal or tax advice. Louisiana plumbing licensing requirements and business formation rules are complex and subject to change. Consult with a Louisiana-licensed attorney and a CPA or tax professional before forming your business to ensure full compliance with all state and local requirements.