HVAC License in Mississippi: Mechanical Classifications, Exams and Fees (2026)

Mississippi does not have an HVAC license.

It has a Mechanical major classification and a Heat, Ventilation, A/C (HVAC) specialty classification underneath it, plus a Residential HVAC classification on the residential side — all issued by the Mississippi State Board of Contractors (MSBOC) to a company, not to a technician. There is no state HVAC journeyman license, no state HVAC master license, and no HVAC-specific state board.

That distinction decides which exam you sit, what you pay, and — the part most guides never reach — who inside your company is legally allowed to hold the thing.

The threshold question comes first

Before anything else, find out whether the state is involved at all. Mississippi regulates by contract value.

• Commercial work over $50,000 requires a commercial license — a Certificate of Responsibility. This applies to subcontractors too, "including equipment installation," which is exactly what a mechanical sub does.
• New residential construction over $50,000 requires a residential license.
• Residential remodeling or additions over $10,000 requires a residential license.
• Subcontractors performing residential electrical, mechanical, HVAC, or plumbing work on a residential construction or improvement project are required to be licensed by MSBOC.

And below the line, MSBOC's own words: "If you are performing residential electrical, plumbing, or HVAC work less than $10,000, a state license is not required, but you must contact the local building official or permit office regarding their requirements."

So a change-out shop doing $7,000 residential replacements is not talking to Jackson. It is talking to its city. A shop chasing a $180,000 rooftop package on a commercial building needs a Certificate of Responsibility with a mechanical classification on it, and needs it before it bids.

Mechanical major vs HVAC specialty: the decision that saves or costs you money

MSBOC runs six major classifications: Building Construction, Electrical, Heavy Construction, Highway Street and Bridge Construction, Mechanical, and Municipal and Public Works. Each major has specialty classifications beneath it, and the board's rule is: "Holding a major classification entitles the license holder to perform the specialty classifications noted within the respective major classification category."

The Mechanical major has fifteen specialties: Boiler Installation and Repair, Cathodic Protection, Ductwork for Heating A/C and Ventilation, Fueling Systems, Heat A/C Ventilation (HVAC), Instrumentation Controls and Energy Management, Insulation for Mechanical Pipes and Duct Work, Irrigation Systems, Millwright, Plumbing, Process Piping, Refrigeration, Swimming Pools, Underground Utilities, and Welding.

So the Mechanical major is a superset of the entire mechanical trade in Mississippi — HVAC and refrigeration and plumbing and boilers and process piping and ductwork — for one classification fee. The HVAC specialty is one slice of it.

Here is the arithmetic that decides it. A commercial application is $400 and includes one trade classification. Every additional classification is $100. A shop that takes HVAC, then adds Refrigeration, then adds Ductwork, then adds Boilers pays $400 + $300 = $700 and is still boxed in. The Mechanical major costs $400 and covers all four plus eleven more.

The offset is the net worth requirement, and it is not small. MSBOC requires a net worth of $50,000 for a major classification and $20,000 for a specialty classification, proven with a reviewed or audited financial statement from a CPA. A young mechanical shop that can document $20,000 but not $50,000 has its answer made for it: take the HVAC specialty now, move up later.

What the Mechanical major actually covers

MSBOC's scope language is long and worth reading closely, because two clauses at the end resolve arguments that come up on real jobs. Verbatim:

"A major classification that involves all aspects of heating, cooling, refrigeration and associated equipment piping and ductwork as well as plumbing work. Scope of work includes installation, maintenance, repair, fabrication, alteration, or extension of central air-conditioning, refrigeration, heating and ventilating systems, including duct work; boiler and unfired pressure vessel systems, lift station equipment and piping, and all appurtenances, apparatus, or equipment used in connection therewith and any duct cleaning and equipment sanitizing which requires partial disassembling of the system; piping, insulation of pipes, vessels and ducts, pressure and process piping, pneumatic control piping, gasoline tanks and pump installations and piping for same, standpipes, air piping, vacuum line piping, oxygen lines, nitrous oxide piping, ink and chemical lines, fuel transmission lines, liquefied petroleum gas lines and natural gas fuel lines; replace, disconnect or reconnect power wiring on the load side of the dedicated existing electrical disconnect switch, install, disconnect and reconnect low voltage heating, ventilating, and air-conditioning control wiring, install condensate drain from an air-conditioning unit to an existing safe waste or other approved disposal other than a direct connection to a sanitary system. This classification includes any incidental excavation work, but does NOT include electrical power wiring."

That middle clause is the electrical boundary, spelled out with unusual precision. A Mississippi mechanical contractor may:

• replace, disconnect or reconnect power wiring on the load side of the dedicated existing electrical disconnect switch;
• install, disconnect and reconnect low-voltage HVAC control wiring; and
• install a condensate drain to an existing approved disposal — but not a direct connection to a sanitary system.

Everything upstream of that disconnect switch is electrical power wiring, and the classification explicitly excludes it. That is the cleanest statement of the HVAC-electrical line we have found in any state's classification scheme, and it is why a Mississippi mechanical shop can set and wire a condenser without an electrical classification but cannot run the circuit to it. For the other side of that line, see our Mississippi electrician license guide.

Note also what the Mechanical major explicitly folds in that the Plumbing specialty explicitly excludes: fuel gas and boiler systems. The Plumbing specialty scope ends with "This classification does NOT include fuel gas or boiler systems." The Mechanical major names LP gas lines and natural gas fuel lines and boiler systems inside its own scope. A gas-fired equipment shop that took Plumbing alone has a gap.

The narrower classifications

Heat, Ventilation, A/C – HVAC (Test Required): "A specialty classification that involves installation, maintenance, repair, fabrication, alteration and extension of heating, ventilating and air condition (HVAC) systems. The scope of work includes HVAC associated equipment, ductwork, duct cleaning, industrial air systems for dust control, ventilation systems and related work."

Refrigeration (Test Required): "A specialty classification that involves commercial and industrial refrigeration work." Terse, and the terseness is the point — this is a separate classification from HVAC. If you do supermarket racks or cold storage, HVAC alone is not obviously your classification.

Ductwork for Heating, A/C and Ventilation (Test Required): "A specialty classification that involves unlimited ductwork for heating, air conditioning and ventilation systems." Sheet metal shops that never touch equipment can license here instead of taking full HVAC.

Boiler Installation and Repair (Test Required): covers "power boiler installations, hot-water heating systems and steam fitting, including fire-tube and water-tube steel power boilers and hot-water heating low pressure boilers," plus associated welding.

Residential HVAC (Test Required): "A residential license classification that involves installation, maintenance, and repair of residential hvac systems. The holder of this classification is limited to residential hvac work only."

Residential Mechanical bundles residential HVAC with residential plumbing — and MSBOC requires both trade exams for it, the Residential HVAC test and the Residential Plumbing test. Two exams, one classification.

Exams — and the NASCLA trap

All MSBOC exams are administered by PSI and all are open book.

Every applicant takes the Mississippi Law and Business Management exam. MSBOC is explicit that it is not a classification: "Mississippi Law and Business Management is not a trade classification; it is a required exam." You do not pay $100 for it.

Then a trade exam, if your classification requires one. The Mechanical major requires one. HVAC requires one. Refrigeration, Ductwork, Boilers and Residential HVAC all require one.

And here is the trap. MSBOC accepts a NASCLA accredited exam in place of a Mississippi exam in exactly two places: the Building Construction major (NASCLA Accredited Examination for Commercial General Building) and the Electrical major (NASCLA Accredited Electrical Examination). Nowhere else. On MSBOC's own classifications page, Building Construction and Electrical carry the subheading "(Trade or NASCLA accredited exam accepted)" and Mechanical does not.

A multi-state mechanical contractor holding a NASCLA credential often arrives assuming it travels. In Mississippi, for mechanical work, it does not. You sit the Mississippi exam.

Sequencing matters as much as content. You cannot book with PSI on your own. MSBOC forwards your qualifier's information to PSI after receiving your application, PSI emails you a confirmation, and only then can you schedule. In the board's words: "No candidate will be allowed to schedule the exam unless MSBOC has sent his or her info to PSI."

PSI sets its own exam fees and they change. Use the PSI Candidate Information Bulletin MSBOC sends you rather than a figure from a third-party site.

What else the application demands

For a commercial application (revised 7/2024):

• Reviewed or audited financial statement from a CPA, completed within the last twelve months, showing $50,000 net worth for a major or $20,000 for a specialty. MSBOC's reasoning: "MSBOC only offers an unlimited license and therefore applicant must demonstrate the required net worth. This is a requirement and cannot be waived or substituted. A Compilation will not be accepted."
• General liability insurance, minimum $300,000 per occurrence and $600,000 aggregate, with MSBOC listed as certificate holder so the board is notified on cancellation. The insured name must match the license name exactly. Residential applicants need proof of coverage but have no minimum.
• Workers' compensation — only if you have five or more employees.
• Three reference letters, one of which must be from your bank or financial institution.
• At least three completed jobs in the classification you are requesting. "Office duties do not qualify."
• Mississippi sales tax or use tax number (statutory, for commercial), plus a Mississippi income tax ID or federal tax ID.
• Proof of good standing with the Mississippi Secretary of State for a corporation, LLC or LLP, with the name matching exactly.
• A U.S. Social Security number for each qualifying party. MSBOC: "Other forms of identification are not acceptable." This is a hard gate and no competing HVAC guide we found mentions it.
• Proof of employment for the qualifying party — covered below.

Two procedural traps. First, applications not completed within 180 days are destroyed, and the fee is non-refundable, so do not file until your CPA statement and bank letter exist. Second, there is a live conflict on MSBOC's own materials: the 7/2024 application PDF still contains a notarized affidavit page, while MSBOC's Apply For A License page says "MSBOC no longer requires an affidavit or a notarized signature on the application form." The instruction page is newer. Call before paying a notary.

Fees

Set by MSBOC and subject to change — verify before you write a check.

• Commercial application: $400 (includes one classification)
• Each additional classification: $100
• Commercial renewal: $400; late fee $50
• Residential application: $50
• Residential renewal: $100; late fee $10
• Commercial name change: $50
• Change in qualifying party: $25
• Inactive status: $25; return to active: $25
• Duplicate license: $50
• Returned check: $40

MSBOC's published fee schedule still carries an effective date of January 1, 2016. Stable for a decade, which is unusual — confirm anyway. PSI exam fees, bond premiums and insurance premiums are separate and set by those providers.

Renewal, inactive status, and the 180-day cliff

Mississippi licenses run one year. MSBOC emails renewal notices about 60 days ahead — and from 2026 the board sends renewal notices by email only. A stale email address in the board's file is now a genuine way to lose a license, not a clerical annoyance.

You can renew up to 180 days after expiration. After that, no renewal is possible and you file a new application: new fee, new financials, potentially new exams.

Inactive status costs $25 and requires returning the license and a written request. You still pay annual renewal fees while inactive, and you may not "submit bids, enter contracts, pull permits, or perform work." Reactivating costs another $25, proof of general liability insurance, and — for commercial holders — financial information again.

And the disciplinary cliff, which is severe: under Board Rule 30-9-802:1.1.3.5, false information in an application or oral interview terminates the Certificate of Responsibility, and no new or renewed COR may be issued "until a period of five (5) years has expired." A misstatement is a five-year exclusion.

The local layer

Because the state thresholds are $10,000 and $50,000, a large share of ordinary residential HVAC work in Mississippi is governed entirely by city and county rules. Jackson, Gulfport and Hattiesburg all run their own. Where Mississippi has journeyman and master tiers, they sit there — in municipal examining boards, not in a state registry.

Miss. Code Ann. § 27-17-457 keeps this from becoming a fifty-jurisdiction problem. It names the trades directly — "any electrical, plumbing, heating and air conditioning, water and sewer, roofing or mechanical contractor" — and provides that a contractor licensed by one Mississippi municipality or county with an examining board that gives a regular written exam may do business in any other municipality or county without a separate license or further examination, provided he furnishes evidence of the license, furnishes evidence that he actually took and passed the written examination, and is not operating a separate place of business there. No additional privilege license bond is required elsewhere if he carries one at home.

Subsection (6) then restricts advertising: a contractor operating on a local privilege license may not advertise as "licensed" without meeting the exam-proof requirement or holding a state license, and must specify "licensed by the city of ___" or "licensed by the State Board of Contractors." The tax officer can suspend the privilege license until you comply.

One limit: § 27-17-457(4) provides that Title 31 Chapter 3 (commercial contractors) and Title 73 Chapter 59 (residential contractors) control where they conflict. Local portability does not excuse a state license over the thresholds.

Who is allowed to hold the license

Everything above describes a company. A company cannot pass an exam.

Mississippi calls the person the qualifying party, and MSBOC's own definition is the clearest in the country: "Every licensed company needs one real, tested person attached to its Certificate of Responsibility — someone who passed the trade exam and stands behind the company's work."

That person must be an owner, officer, member of the executive staff, or responsible managing employee. MSBOC does not take it on trust. The application has a checkbox:

"Proof of employment attached: ☐ check stub ☐ W-2 form ☐ MS SOS listing"

directly beside a "Date Hired" field. Mississippi asks for the W-2 by name, on the form, next to the hire date. The single exemption — "Proof of employment is not required if applying in an individual name" — exists only because a sole proprietor cannot employ himself.

MSBOC then states what the role requires, and this is the language to remember:

"Work there — really employed by the company, provable at application and renewal." "Do the work — actively engaged in the licensed trade, not just on paper."

"Provable at renewal" makes it a continuing obligation. Mississippi does not check once.

Three operating limits:

• Three-entity cap. A qualifying party may serve no more than three separate entities without appearing before the board for special permission.
• Multiple qualifiers allowed. Different people can qualify different classifications — and one person can sit the trade exam while another sits Law and Business Management.
• 90 days to replace. If the qualifier disassociates, replacement must be made within 90 days or the company gets a hearing notice to show cause why the Certificate of Responsibility should not be suspended or revoked. Notice can come from the company or from the departing qualifier.

And a protection most states do not offer: if your license carries multiple classifications and the qualifiers for the others remain, "the licensee may continue to operate in the remaining class or classes." Only the departed qualifier's class comes off, on the day of the hearing. A mechanical shop holding both HVAC and Refrigeration under separate qualifiers does not lose everything when one leaves.

The mechanics of that role — the $25 change fee, the two-way notification duty, the exclusivity limits — are in our Mississippi Certificate of Responsibility and qualifying party guide.

The practical path

For most Mississippi mechanical contractors the sequence is:

1. Decide whether your work crosses the $10,000 or $50,000 threshold. If not, go to your city or county.
2. Decide between the Mechanical major ($50,000 net worth, covers everything) and a specialty like HVAC or Refrigeration ($20,000 net worth, narrower scope). Price the additional-classification math before you choose.
3. Line up the CPA statement, the GL certificate at $300,000/$600,000 with MSBOC as certificate holder, three reference letters including one from your bank, your tax numbers, and three completed jobs in the classification.
4. Identify the qualifying party, confirm they have a U.S. SSN, and gather the check stub or W-2.
5. File. Do not let it sit past 180 days.
6. Wait for the PSI confirmation email, then schedule the Law and Business Management exam and the trade exam.
7. Board review is weekly; the license follows in roughly a week to ten days.

Step 4 is where companies stall. Financials and insurance are solvable with a checkbook. A person who can pass the Mississippi mechanical exam and be genuinely employed by your company is not.

If nobody in-house qualifies, you either develop someone over years or you hire someone who already holds the credential. A qualifying agent is a licensed professional employed full-time by your company to hold the classification. In Mississippi that relationship has to be real employment — the board asks for the W-2 by name and re-checks it at renewal, and its own standard is "not just on paper."

The Licensing Company places qualifying agents as full-time W-2 employees only — never on a percentage, never per project, never as a 1099. That is the only structure a Mississippi application survives, and it is the same structure we apply for HVAC contractors nationally. Start with a consultation, or go directly to hiring a qualifying agent.

Frequently asked questions

Does Mississippi require an HVAC license? For commercial work over $50,000, new residential construction over $50,000, or residential remodeling over $10,000 — yes, from MSBOC, as a Mechanical major or an HVAC specialty on a Certificate of Responsibility, or as a Residential HVAC license. Residential subcontractors performing HVAC work on a residential construction or improvement project must also be licensed. Below the thresholds the state does not license you, but your city or county probably does.

Is there a Mississippi journeyman or master HVAC license? Not at the state level. MSBOC licenses companies by classification. Journeyman and master tiers exist in Mississippi inside municipal and county examining boards.

Mechanical major or HVAC specialty — which do I need? Mechanical covers HVAC, refrigeration, plumbing, boilers, ductwork, process piping and nine more, but demands $50,000 net worth. HVAC alone demands $20,000 and covers HVAC only. If you expect to add two or more mechanical specialties, the major is usually cheaper and always broader.

Can my NASCLA exam substitute for the Mississippi mechanical exam? No. MSBOC accepts NASCLA accredited exams only for the Building Construction major and the Electrical major.

Can a mechanical contractor do electrical work on a unit? Within a defined boundary. The Mechanical classification permits replacing, disconnecting or reconnecting power wiring on the load side of the dedicated existing electrical disconnect switch, and installing and reconnecting low-voltage HVAC control wiring. It expressly does not include electrical power wiring. Running the circuit to the disconnect is electrical work.

How much does it cost to get HVAC licensed in Mississippi? The board fees are fixed and published: $400 commercial including one classification, $100 per additional classification, $50 residential. The rest varies — your CPA's fee for a reviewed or audited financial statement, your insurance premium, PSI's exam fees, and, if you need to bring in a qualifying party, the cost of that placement. That last one depends on the classification, the risk, and the volume of work, which is why we quote it privately. A consultation gets you a number for your actual situation.

What happens if my qualifying party leaves? 90 days to replace, with notice from either side. Miss it and you face a hearing on suspension or revocation. If your license holds more than one classification and the other qualifiers stay, you keep those classes and lose only the departed qualifier's. Our contractor qualifier contingency plan covers how to prepare for this in advance.

Can the qualifying party be an independent contractor? Mississippi's application asks for a check stub or W-2 as proof of employment, requires it at renewal as well as application, and describes the role as "really employed by the company" and "actively engaged in the licensed trade, not just on paper." We compare how boards nationally treat this in can a qualifying agent be a 1099 contractor.

Fees, thresholds, classifications and scope language in this guide come from the Mississippi State Board of Contractors and are subject to change. Verify with the board at 601-354-6161 or 800-880-6161, or at msboc.us, before relying on them. PSI sets its own examination fees. Statutory references are to the Mississippi Code of 1972 as currently published. This guide covers the licensing process; it is not exam preparation and it is not legal advice.

Related: Mississippi plumbing license · Mississippi electrician license · Mississippi contractor licensing overview · Alabama HVAC license · Louisiana HVAC license · Tennessee HVAC license · All state guides