Mississippi HVAC Contractor Classifications

The Mississippi State Board of Contractors (MSBOC) doesn't issue a generic "HVAC license." It assigns specific classifications that define exactly what scope of work you're authorized to perform, what financial requirements you must meet, and which exams you need to pass. Choosing the wrong classification — or operating outside the scope of one you hold — can result in license suspension, lost lien rights, or civil penalties.

Here's how the classifications break down for HVAC and mechanical work.

Residential Classifications

Residential HVAC restricts you to installing, maintaining, and repairing heating and cooling systems on residential structures — buildings occupied by 50 or fewer families and no more than three stories in height.

Requirements:

• No state-mandated minimum experience years
• Documentation of three completed residential projects
• Professional references
• $50 application fee
• Bank reference letter verifying active, stable accounts (residential subcontractors have no set net-worth minimum)
• CPA-prepared financial statement required for a residential license
• Pass the Law and Business Management Exam + Residential HVAC Trade Exam
• 2 hours of annual continuing education for licenses issued on or after July 1, 2015

Residential Mechanical is broader. It covers both HVAC and plumbing systems within the same residential building parameters. If you want to handle plumbing alongside HVAC on residential projects, this is the classification — but you'll need to pass both the Residential HVAC and Residential Plumbing trade exams.

Commercial Specialty Classifications

Heat, Ventilation, Air Conditioning (HVAC) — this is the commercial specialty classification most HVAC contractors target. It authorizes:

• Installation, maintenance, repair, fabrication, alteration, and extension of comfort HVAC systems
• Associated ductwork and duct cleaning
• Industrial air systems for dust control
• Related ventilation work

It does not authorize plumbing, electrical, or refrigeration work outside of comfort systems.

Requirements:

• Four years of verifiable journeyman-level experience
• CPA-reviewed financial statement showing $20,000 minimum net worth
• $300,000/$600,000 CGL insurance
• $400 application fee
• Pass the Law and Business Management Exam + HVAC Trade Exam (80 questions, 4 hours)
• No annual CE requirement

Refrigeration is a separate commercial specialty. It strictly covers commercial and industrial refrigeration installations — walk-in coolers, blast freezers, display cases. It does not cover residential or light commercial comfort heating and cooling. If your business model includes both comfort HVAC and commercial refrigeration, you need both classifications (or the Major Mechanical).

Ductwork for Heating, A/C, and Ventilation restricts you to sheet metal and flexible air-distribution duct systems — fabrication, installation, and modification only. No equipment, no controls, no refrigerant work.

Boiler Installation and Repair covers commercial, industrial, or residential boilers and associated steam and gas piping. Relevant if your HVAC work includes hydronic heating systems in commercial buildings.

The Major Mechanical Classification

Mechanical Contractor (Major) is the broadest credential available for mechanical systems. Holding a major classification automatically covers all specialty classifications beneath it — HVAC, Refrigeration, Ductwork, and Boiler — without separate exams or additional classification fees. It also includes plumbing.

Requirements:

• Four years of verifiable experience
• CPA-reviewed financial statement showing $50,000 minimum net worth
• $300,000/$600,000 CGL insurance
• $400 application fee
• Pass the Law and Business Management Exam + Commercial Mechanical Trade Exam (100 questions, 4 hours)
• No annual CE requirement

The $50,000 net worth threshold is the primary barrier. If you can meet it, the Major Mechanical classification gives you the widest operating authority with a single license.

Choosing the Right Classification

The decision comes down to three factors: scope of work, financial capacity, and experience.

If you're doing residential work only and don't plan to take commercial contracts, Residential HVAC is the fastest and cheapest path — no experience-years requirement, $50 application fee, and no set net-worth minimum when applying as a residential subcontractor.

If you want commercial HVAC work but don't need plumbing or refrigeration authority, the Commercial HVAC Specialty classification at $20,000 net worth is the entry point.

If you want maximum flexibility to bid on any mechanical project — HVAC, plumbing, refrigeration, ductwork, boilers — the Major Mechanical classification costs more up front ($50,000 net worth) but eliminates the need for separate classifications.

One important nuance: you can add classifications to an existing license. The MSBOC charges $100 per classification addition. So you could start with Residential HVAC, build your business and net worth, then add Commercial HVAC Specialty when you're ready to take commercial projects.

The Qualifying Party Constraint

Each classification requires a qualifying party (QP) — the individual who passes the exams. The QP must be an owner, officer, or responsible managing employee of the business. One QP can serve up to three separate business entities without special board permission.

If you hold multiple classifications, the same QP can cover them all — or different individuals can qualify separate classifications within the same company.

The Mississippi HVAC License Guide includes the complete MSBOC classification matrix with the net worth requirements, exam specifications, and approved reference books for each classification level.

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