Mississippi · HVAC licensing · official-source guide
The Mississippi State Board of Contractors licenses HVAC contracting at the state level, through the Mechanical major classification and its specialties for commercial work and the Residential HVAC or Residential Mechanical classification for residential work. Any HVAC subcontractor on a residential job needs a license at any dollar amount. Technicians who touch refrigerant also need separate federal EPA Section 608 certification.
Verified against agency sources on 2026-09-12. Rules and fees change; confirm with the named authority before relying on this guide.
Mississippi does not run a separate HVAC or mechanical board. HVAC contracting is licensed by the Mississippi State Board of Contractors, the same agency that licenses building, electrical, plumbing, roofing and every other construction trade in the state. The board was created under Miss. Code Ann. Title 31, Chapter 3 and traces to 1952, and it is made up of members appointed by the governor who set licensing policy and hire an executive director to run the agency day to day. Its offices are at 2679 Crane Ridge Drive, Suite C, Jackson, Mississippi 39216, with a mailing address of P.O. Box 320279, Jackson, Mississippi 39232, and a main line of 601-354-6161 or 800-880-6161. Two separate bodies of law run through this one board. Commercial licensing sits in Miss. Code Ann. Sections 31-3-1 through 31-3-23, and the credential it issues is called a certificate of responsibility. Residential licensing sits in Miss. Code Ann. Section 73-59-1 and following, and the credential it issues is called a residential license. The board publishes both statutes together with its own administrative rules as the Commercial Laws and Rules and the Residential Laws and Rules. An HVAC contractor who works on both commercial and residential projects in Mississippi has to read both bodies of law, because the dollar thresholds, the fees, the insurance minimums and the continuing education duty differ between them. Nothing in either chapter creates a stand-alone HVAC board, a stand-alone mechanical board, or a state journeyman or master HVAC technician credential separate from the contractor license itself.
Mississippi does not issue a personal HVAC technician license the way some states issue a journeyman card. It licenses the contracting business, commercial or residential, and attaches that license to a named individual the statute calls the qualifying party. Miss. Code Ann. Section 31-3-13(a) and Commercial Rule 1.1(2)(l) define the qualifying party as the owner, a responsible managing employee, a responsible managing officer, or a member of the executive staff who sits for the required examination on behalf of the applicant. The qualifying party is the person who holds the exam scores, must be regularly employed by the license holder, and must be actively engaged in the classification of work being qualified for. The license holder must furnish proof of that employment at application and at every renewal, and a qualifying party may serve no more than three separate entities without first appearing before the board for special permission. If the qualifying party leaves the company, both the qualifying party and the license holder must notify the board in writing immediately, and a replacement qualifying party must be found within 90 days or the certificate of responsibility or residential license is subject to suspension or revocation. If the license carries more than one classification and the qualifier for another classification stays on, the company can keep operating in that remaining classification while the disassociated classification is dropped. In practical terms, an HVAC company's right to bid, contract and pull permits in Mississippi rides on one named person staying attached to the license, not on every technician the company employs holding a state card.
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On the commercial side, HVAC sits inside the Mechanical major classification, one of six major classifications Commercial Rule 1.1(3)(b) lists alongside Building Construction, Electrical Work, Highway Street and Bridge Construction, Heavy Construction, and Municipal and Public Works Construction. The board's classifications page defines Mechanical as covering all aspects of heating, cooling, refrigeration and associated equipment piping and ductwork, as well as plumbing work, including installation, maintenance, repair, fabrication, alteration or extension of central air conditioning, refrigeration, heating and ventilating systems and duct work, boiler and unfired pressure vessel systems, and related piping. A trade exam is required for the Mechanical major classification. Holding the major classification lets the license holder perform every specialty classification listed under it, so a contractor does not need to also hold each specialty separately. Six specialty classifications sit under Mechanical and are directly relevant to HVAC and refrigeration work: Boilers, which covers boiler installation and hot water heating systems; Ductwork for Heating, A/C and Ventilation, covering unlimited ductwork for heating, air conditioning and ventilation systems; Heat, Ventilation, A/C, described by the board as installation, maintenance, repair, fabrication, alteration and extension of HVAC systems including associated equipment, ductwork, duct cleaning and industrial air systems for dust control; Plumbing; Process Piping; and Refrigeration, covering commercial and industrial refrigeration work. A contractor who wants only one specialty, such as the HVAC specialty alone, can apply for that specialty without the full Mechanical major classification, and one specialty selection is included in the application fee with a $100.00 charge for each additional one chosen.
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Residential HVAC work runs on a separate, narrower set of classifications from the commercial side, and none of them carry over to commercial jobs. The board's classifications page lists nine residential classifications, and three cover HVAC and related mechanical trades. Residential HVAC is a residential license classification limited to installation, maintenance and repair of residential HVAC systems, with the holder limited to residential HVAC work only, and a trade test is required. Residential Mechanical combines HVAC and plumbing scope in one classification, defined as installation, maintenance and repair of residential HVAC and residential plumbing systems, and it requires passing both the Residential HVAC test and the Residential Plumbing test, since it is not a shortcut around either exam. Residential Plumbing is its own separate classification for contractors who want plumbing scope without HVAC. A holder of any of these three classifications is limited strictly to the trade named on the license and cannot use it to justify performing general residential construction, remodeling or roofing work, which sit under the separate Residential Builder and Residential Remodeler classifications. The board also licenses Residential Solar as its own classification, and its own definition specifically notes that a residential solar contractor must also hold the required classification to make the mechanical or electrical connections a solar installation needs, which matters for an HVAC contractor who adds heat pump or solar thermal work to their scope. Every residential classification listed here requires a written trade examination graded at a minimum passing score of 70 percent.
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The commercial and residential thresholds differ, and the residential threshold has a carve out that catches most HVAC contractors regardless of job size. Miss. Code Ann. Section 31-3-1 excludes from the definition of contractor any commercial contract or undertaking under $50,000.00, so a commercial HVAC installation or service contract has to reach that figure before a certificate of responsibility is legally required. On the residential side, Miss. Code Ann. Section 73-59-1 defines a residential builder as someone building a new residence where the total cost exceeds $50,000.00, and a remodeler as someone improving an existing residence where the cost exceeds $10,000.00. Those two numbers describe the general contractor's own threshold. They do not describe the HVAC trade's threshold. Miss. Code Ann. Section 73-59-3(1)(d) separately requires a license of any subcontractor, of any tier, performing electrical, plumbing, mechanical, or heating, ventilation and air conditioning work on any residential construction or residential improvement project, and the statute states plainly that this applies no matter the dollar amount of the construction or improvements. In practice that means an HVAC subcontractor working under a residential builder or remodeler needs a Mississippi HVAC or Mechanical license for a single service call as much as for a whole-house system replacement, with no dollar floor to hide under. The board's own consumer FAQ page confirms this reading directly, stating that subcontractors performing residential electrical, mechanical, HVAC or plumbing work on a residential construction or improvement project are required to be licensed by MSBOC.
Every applicant, commercial or residential, takes the Mississippi Law and Business Management exam, and most classifications also require a separate trade exam on top of it. For the Mechanical major classification and its HVAC-related specialties, and for the Residential HVAC, Residential Mechanical and Residential Plumbing classifications, that means passing a dedicated trade exam in addition to the business and law exam. Commercial Rule 1.1(9) sets the passing score for the commercial trade examination at a minimum grade of 70 percent, and Residential Rule 1.1(m) sets the same 70 percent minimum for residential exams. All exams are administered by PSI, and the board's own application guidance describes the exams as open book, with a Candidate Information Bulletin mailed to each applicant explaining which books are allowed and where to get them. The sequence runs in a fixed order: submit the application, wait for the board to review it, and only after the board sends the qualifying party's information to PSI can that person schedule a test date, time and location. Applicants who cannot take a written exam may request an oral examination instead, for a $50.00 fee. The board can also waive an exam entirely for a qualified applicant, for a separate $50.00 fee, most commonly for an applicant relying on reciprocity credit from another state's HVAC, mechanical or plumbing exam. Applicants have 180 days from the date the application is filed to finish the entire process, including testing, before an incomplete file is destroyed and a new application and fee are required.
The board publishes one fee schedule, Commercial Rule 3.4, sourced to Miss. Code Ann. Sections 31-3-13(g) and 73-59-11(f), and it covers both the commercial and residential side of an HVAC license. A commercial application for one classification, such as Mechanical or the HVAC specialty, costs $400.00, and each additional classification added to that same license costs $100.00. Commercial license renewal costs $200.00 a year, with a $50.00 late fee if it is renewed after the expiration date. A commercial name change costs $50.00, moving a commercial license to inactive status costs $25.00, reactivating it costs another $25.00, and a duplicate commercial license costs $50.00. Verifying or transferring a license under a reciprocity agreement costs $25.00. On the residential side, which covers the Residential HVAC, Residential Mechanical and Residential Plumbing classifications, the initial application fee is $50.00 and annual renewal is $100.00, with a $10.00 late fee. Moving a residential license to inactive status costs $25.00, reactivating it costs $25.00, and a duplicate residential license costs $50.00. A request to waive an exam costs $50.00, a request for an oral examination costs $50.00, and a request to change the qualifying party on either a commercial or residential license costs $25.00. Public information requests cost 50 cents per page plus a $25.00 administrative charge, the board's full mailing list of active contractors costs $500.00, and a returned check costs $40.00. None of these fees are refundable once the application is filed.
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Insurance minimums differ sharply between the two license tracks, and an HVAC contractor working both commercial and residential jobs has to carry the higher commercial standard to stay eligible for both. Commercial Rule 1.1(2)(j) requires every applicant for a certificate of responsibility, new or renewal, to provide a certificate of insurance showing current general liability coverage of at least $300,000.00 per occurrence and $600,000.00 aggregate, with the Mississippi State Board of Contractors named as certificate holder so it is notified if the policy is cancelled, and with the insured name on the certificate matching the exact name the license is issued under. A current workers compensation certificate is also required where state law requires that coverage. On the residential side, Residential Rule 1.1(k) requires a certificate of general liability insurance naming the board as certificate holder, but sets no minimum dollar amount, only requiring proof that coverage exists. Residential Rule 1.1(j) separately requires proof of workers compensation coverage where applicable, along with a federal employer identification number or Social Security number. Both tracks exempt a license placed on inactive status from the insurance duty: Commercial Rule 1.1(12) drops the Rule 1.1(2)(j) insurance requirement while a certificate is inactive, and Miss. Code Ann. Section 73-59-3(3) does the same for an inactive residential license. Reactivating either license means providing current proof of coverage again before the board will restore active status, and a commercial applicant must also resubmit the financial information the inactive period waived.
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Mississippi runs a financial screening step on commercial HVAC applicants that has no residential equivalent. Commercial Rule 1.1(2)(i) requires an applicant for a new certificate of responsibility to furnish, at minimum, a reviewed financial statement completed within the prior twelve months, prepared and signed by a certified public accountant, showing the applicant's assets, liabilities and net worth. The board uses that statement to judge whether the applicant is financially able to perform work of $50,000.00 or more, the same figure that triggers the commercial licensing threshold in the first place. An applicant for a major classification, which includes the Mechanical major classification that covers full-scope HVAC and mechanical work, must show a net worth of at least $50,000.00. An applicant for a specialty classification only, such as the HVAC specialty or the Refrigeration specialty taken on its own without the Mechanical major classification, must show a net worth of at least $20,000.00 instead. The rule states this financial statement and any other financial information submitted with it is confidential, and it specifically does not require an audited statement, only a reviewed one. Renewal applicants have a lighter duty: they submit a balance sheet prepared under generally accepted accounting principles rather than a fresh reviewed statement. There is no financial statement or net worth requirement on the residential side at all. A residential HVAC or Residential Mechanical applicant only has to meet the insurance and workers compensation proof requirements described elsewhere in this rule set, not a net worth test.
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Both the commercial and residential HVAC license run on an annual cycle, and both allow a 180 day grace period after expiration before a fresh application becomes mandatory. Commercial Rule 1.1(2)(h) and Miss. Code Ann. Section 31-3-13(a) state that all original certificates of responsibility expire one year from the date of issuance, that the privilege tax behind the certificate is an annual tax, and that the certificate holder has a duty to renew every year whether or not the board sends a reminder notice. Commercial Rule 1.1(2)(m) requires an applicant whose certificate has been expired at least 180 days to submit a brand new application with everything a first-time applicant would submit, rather than a simple renewal. On the residential side, Miss. Code Ann. Section 73-59-3(5) sets the license to expire on the last day of the twelfth month after issuance or renewal, and allows renewal within 180 days after that expiration date on payment of the renewal fee. Continuing education applies only to the residential license, not the commercial certificate of responsibility. Residential Rule 1.4, adopted under Miss. Code Ann. Section 73-59-11, requires each qualifying party on a residential license issued on or after July 1, 2015 to complete two continuing education credit hours a year from a board-approved provider or instructor, with a credit defined as a 50 minute hour of instruction. Proof of the two hours is submitted with the renewal application, hours do not carry over from one renewal period to the next, and the board publishes its own searchable list of approved continuing education providers, instructors and courses rather than dictating specific courses.
Mississippi's reciprocity list waives only the trade exam and never the Mississippi Law and Business Management exam, and the board is explicit that each agreement varies and may not cover every classification. For an HVAC contractor moving into Mississippi, several listed agreements name the trade directly. The Alabama Heating and Air agreement waives the exam for a current Alabama Heating and Air license holder who has taken the Alabama exam. The Alabama General Contractors Board agreement waives all exams except Mechanical and Plumbing, and specifically notes it can waive HVAC within that Mechanical grouping. The Arkansas Contractors Licensing Board agreement waives all exams except any type of mechanical work, and the board's own list names plumbing, boilers, process piping and HVAC as the mechanical trades excluded from that waiver, meaning an Arkansas-licensed HVAC contractor still has to sit the Mississippi mechanical trade exam. The Louisiana Licensing Board for Contractors entry states Louisiana can waive HVAC specifically, while it cannot waive the broader Mechanical or Plumbing classifications, and the board notes that even though the formal reciprocity agreement with Louisiana has ended, it still recognizes a passing Louisiana exam score and will waive the Mississippi trade exam for a qualifying applicant on that basis. The Ohio Construction Industry Licensing Board agreement waives the exam specifically for Electrical, HVAC, Plumbing and Refrigeration classifications for a current Ohio license holder with no discipline in the past year. Tennessee is the only state the board lists as waiving all exams, including Mechanical and Plumbing. Military members, military spouses and applicants under the Universal Recognition of Occupational Licensure Act have a separate reciprocity path under Miss. Code Ann. Sections 73-50-1 and 73-50-2.
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The commercial and residential chapters carry different penalties, and an HVAC contractor can be caught under either one depending on the job. On the commercial side, Miss. Code Ann. Section 31-3-21(1) makes it unlawful for anyone without a certificate of responsibility to submit a bid, enter a contract, or otherwise engage in the business of a contractor as the chapter defines it. Knowingly and willfully submitting a bid without a certificate is a misdemeanor, punishable on conviction by a fine of not more than $1,000.00, imprisonment of not more than six months, or both. Section 31-3-21(2) attaches the identical misdemeanor and the identical fine and jail exposure to submitting a bid over $50,000.00 without the certificate number printed on the outside of the bid envelope. Section 31-3-21(4) adds a civil route on top of the criminal one: after notice and a hearing, the board can order an unlicensed contractor to stop work and can impose a civil penalty of up to three percent of the total value of the contract being performed, a figure that scales upward on a large commercial mechanical job. On the residential side, Miss. Code Ann. Section 73-59-9(1) makes undertaking residential construction or improvement work without a valid license, or filing false information to obtain one, a misdemeanor punishable by a fine of not less than $100.00 and not more than $5,000.00, or imprisonment of 30 to 60 days in the county jail, or both. Section 73-59-9(2) then strips an unlicensed contractor's contract rights outright: that contractor cannot sue to enforce the contract at all, and can recover only documented labor and material expenses proven by clear and convincing evidence. Section 73-59-9(3) lets the board issue a citation and stop the work on the spot.
Mississippi does not have a general statute telling an HVAC contractor to print a license number on advertising, business cards or vehicles, and none of the board's published rules or the two law and rules documents it maintains contain such a requirement. What the state does require is narrower and tied to bids, jobsites and contracts specifically. Miss. Code Ann. Section 31-3-21(2) requires every commercial bid over $50,000.00, public or private, to carry the contractor's current certificate of responsibility number on the outside of the bid envelope or container, or a statement that the bid does not exceed $50,000.00, and a bid missing that number cannot be opened or considered. Residential Rule 1.2, adopted under Miss. Code Ann. Section 73-59-11(f), requires that once a building permit is issued to a residential builder, remodeler or certificate of responsibility holder, that contractor must post a sign at the permitted jobsite showing the license or certificate number and the issuing state, in lettering at least two inches high and twelve inches wide. Both chapters also require a written insurance disclosure on the contract itself. Miss. Code Ann. Section 31-3-13 requires a commercial certificate holder to disclose in writing, before the owner signs the contract, whether the holder carries general liability insurance, in bold, conspicuous type larger than the rest of the contract text. Residential Rule 1.3 requires the same disclosure from a residential builder, remodeler or roofer, in a fixed form of words naming the insurer and policy number, placed immediately above the purchaser's signature line. An HVAC contractor who skips either disclosure is not meeting a formality the board treats as optional.
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The board runs a free public license search, called Search Contractor, at search.msboc.us, and it is the tool a homeowner, general contractor or building official should use before hiring or subcontracting HVAC work. A search by name returns the license or certificate number, its current status, and its expiration date. Two details matter more than a simple active or inactive flag. First, check the classification actually listed on the license. Commercial Rule 1.1(3)(a) states that a license holder is not permitted to bid on or perform work outside the classifications listed on the application, so a company holding only a Building Construction classification is not licensed to perform Mechanical or HVAC specialty work even if it holds a valid certificate for something else. Second, check whether the license is commercial, residential, or both, because a Residential HVAC classification limits the holder strictly to residential HVAC work and cannot be used to justify bidding a commercial mechanical contract. The board's own application guidance also warns that a contractor must operate under the exact name printed on its certificate of licensure, and that operating under any other name is treated as unlicensed construction, so a mismatch between the name on an estimate and the name the search tool returns is itself a warning sign. The board additionally publishes a violators page and takes consumer complaints through its enforcement and hire-a-contractor pages, giving a customer a way to check whether a contractor has an open disciplinary history before signing a contract.
A Mississippi state HVAC license does not replace local business licensing or local permitting, and the two largest cities show what that local layer looks like. Jackson, the state capital and largest city, requires every business operating inside city limits, HVAC contractors included, to obtain a business license through its Business Licensing Division at 200 South President Street. The city's process includes a notarized privilege tax form for both new applications and renewals, proof of good standing with the Mississippi Secretary of State, and a license that must be renewed every year during the month it expires. Jackson separately lists mechanical permits among the standard residential permit types its building department requires for HVAC installation, replacement and related work, alongside building, roofing, electrical and plumbing permits, with inspections scheduled at each stage of the work and final approval required before the project is considered complete. Gulfport, on the coast, runs its own contractor licensing process through its Urban Development Building Code Services division, requiring a notarized application, a copy of the applicant's Mississippi State Board of Contractors license, proof of public liability insurance of at least $100,000.00 per occurrence and $300,000.00 aggregate naming the city as certificate holder, and a $100.00 contractor licensing fee that is waived for an applicant who already holds a state certificate of responsibility. Gulfport charges HVAC and mechanical work separately under its own mechanical permit fee schedule, starting with a $30.00 base permit fee plus a valuation-based charge starting at $20.00 for the first $1,000.00 of installation value, plus separate boiler inspection fees scaled by Btu input and a $30.00 fee for a temporary operation inspection of a heating, ventilating or air conditioning system.
Sourcesjacksonms.gov 1jacksonms.gov 2gulfport-ms.gov 3cms3.revize.com 4
A Mississippi HVAC license from the State Board of Contractors covers state contracting law only. It does not include, replace, or substitute for the separate federal refrigerant handling certification the United States Environmental Protection Agency requires of individual technicians. Under Section 608 of the Clean Air Act and its implementing regulations at 40 CFR Part 82, Subpart F, any technician who maintains, services, repairs or disposes of equipment that could release refrigerant into the atmosphere must hold Section 608 Technician Certification, and this obligation attaches to the individual person doing the work, not to the Mississippi business entity holding the state Mechanical, HVAC or Refrigeration license. The EPA defines a technician for this purpose as anyone who attaches or detaches hoses and gauges to measure pressure in an appliance, adds or removes refrigerant, or otherwise violates the integrity of a motor vehicle air conditioner-like appliance or a small appliance, other than for disposal. Apprentices working under close, continual supervision of a certified technician are exempt from the certification duty themselves. EPA has created four certification types: Type I for servicing small appliances, Type II for servicing or disposing of high or very high pressure appliances other than small appliances and motor vehicle air conditioners, Type III for servicing or disposing of low pressure appliances, and Universal certification for all equipment types, which requires the core exam to be proctored rather than open book. Every technician must pass an EPA-approved test through an EPA-approved certifying organization, and the resulting certification does not expire once earned. A Mississippi HVAC or Refrigeration license holder who employs technicians handling refrigerant needs each of those technicians individually Section 608 certified, on top of, not instead of, the company's state license.
Sourcesepa.gov
These are common details other guides publish about Mississippi, but we could not verify them from the agency source. Confirm them directly before relying on them.
Yes. The Mississippi State Board of Contractors licenses HVAC work through the Mechanical major classification and its specialties on the commercial side, and through the Residential HVAC or Residential Mechanical classification on the residential side. There is no separate HVAC board and no free-standing state technician card apart from these contractor license classifications.
Miss. Code Ann. Section 31-3-1 excludes any commercial contract under $50,000.00 from the licensing requirement. Bids over $50,000.00 must also carry the contractor's certificate of responsibility number on the outside of the bid envelope under Section 31-3-21(2), or the bid cannot be opened or considered.
Yes, at any dollar amount. Miss. Code Ann. Section 73-59-3(1)(d) requires a license for any subcontractor performing heating, ventilation and air conditioning work on a residential construction or improvement project, no matter the dollar amount involved. The $10,000.00 remodeler and $50,000.00 builder thresholds apply to the general contractor, not to the HVAC trade.
Every applicant takes the Mississippi Law and Business Management exam. Applicants for the Mechanical classification, its HVAC-related specialties, or the Residential HVAC and Residential Mechanical classifications also take a dedicated trade exam. All exams are administered by PSI, are open book, and require a minimum passing grade of 70 percent.
Partly. Reciprocity only waives the trade exam, never the Mississippi Law and Business exam. The Ohio Construction Industry Licensing Board agreement waives the exam for Electrical, HVAC, Plumbing and Refrigeration classifications, and Alabama Heating and Air is waived directly, but Arkansas and the Alabama General Contractors Board still require the Mississippi mechanical trade exam.
A commercial application for one classification costs $400.00, with $100.00 for each additional classification, and commercial renewal costs $200.00 a year with a $50.00 late fee. A residential application costs $50.00, and residential renewal costs $100.00 a year with a $10.00 late fee.
Commercial Rule 1.1(2)(j) requires a certificate of general liability insurance showing at least $300,000.00 per occurrence and $600,000.00 aggregate, naming the Mississippi State Board of Contractors as certificate holder, plus workers compensation coverage where state law requires it. Residential applicants must show proof of liability coverage but face no fixed dollar minimum.
Yes. Commercial Rule 1.1(2)(i) requires a reviewed financial statement from a certified public accountant. An applicant for the Mechanical major classification needs a net worth of at least $50,000.00, and an applicant for a specialty classification alone, such as HVAC or Refrigeration, needs a net worth of at least $20,000.00. Residential applicants face no net worth test.
Both licenses renew annually, with a 180 day grace period after expiration. Continuing education applies only to the residential license: each qualifying party on a residential license issued on or after July 1, 2015 must complete two continuing education credit hours a year from a board-approved provider under Miss. Code Ann. Section 73-59-11.
On commercial jobs, unlicensed bidding or contracting is a misdemeanor punishable by a fine up to $1,000.00, up to six months in jail, or both, plus a possible civil penalty of up to three percent of the contract value. On residential jobs, it is a misdemeanor punishable by $100.00 to $5,000.00 or 30 to 60 days in jail, and the unlicensed contractor loses the right to sue to enforce the contract.
No. The Mississippi State Board of Contractors license covers state contracting law only. Any technician who handles refrigerant, adds it, removes it, or services equipment that could release it, must separately hold EPA Section 608 Technician Certification under the Clean Air Act, a federal credential attached to the individual technician, not the company license.
Use the board's free Search Contractor tool at search.msboc.us to confirm the license number, status and expiration date, and check that the classification listed actually covers Mechanical, HVAC or Refrigeration work rather than a different trade. Also confirm the business name matches exactly, since operating under another name is treated as unlicensed construction.
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