Sales tax and bookkeeping for HVAC, plumbing and electrical contractors in North Carolina

Since 2017 North Carolina taxes repair, maintenance and installation services on real property, and anyone doing that work must register and collect even if it is their only business. By statute, work on a building is a taxable service unless the contractor can prove it was a real property contract for a capital improvement. The burden of proof sits with you.

• The statutory capital improvement list includes replacement or installation of a heating or air conditioning unit or an HVAC system, and replacement or installation of a septic system, roof, plumbing or electrical system, plus new construction, remodeling and work that needs a State Building Code permit.

  Source: NCDOR, Real Property Contracts

• The same list carves out the small items. The HVAC item does not include gas logs, water heaters or pool heaters, and the plumbing and electrical item does not include electrical or plumbing components, water heaters or gutters, outside new construction or remodeling.

  Source: NCDOR, Real Property Contracts

• The state's chart, HVAC: installing or replacing a central air conditioning unit or system, complete replacement of a heating system, or replacing an entire ductwork system is a capital improvement. Repairing or replacing blowers, coils, control devices or ductwork sections is taxable, as is complete replacement of a window unit. Duct cleaning is exempt.

  Source: NCDOR, Services to Real Property Taxability Chart

• Plumbing: repairing, installing or replacing a water heater is taxable, including a tank to tankless swap. So is replacing sinks, toilets, tubs and fittings, repairing pipes, stopping leaks, thawing pipes and unclogging drains. New piping additions with a permit, excavation for a piping system and septic system replacement are capital improvements. Pumping a septic tank is exempt.

  Source: NCDOR, Services to Real Property Taxability Chart

• Electrical: complete rewiring, whole-residence or commercial generator installation, and wiring changes that need a permit are capital improvements. Repairing or replacing components, breakers and outlets in existing property is taxable. Swapping fixtures for LED is taxable unless new wiring and a permit are involved.

  Source: NCDOR, Services to Real Property Taxability Chart

• The taxable sales price includes the cost of materials, labor or service costs and installation charges. Separately stating installation does not avoid tax on a repair job.

  Source: NCDOR, Repair, Maintenance and Installation Services

• Mixed jobs: when the taxable repair work is 25% or less of the contract price, the whole contract is treated as a real property contract and no tax is charged to the customer. Above 25%, tax applies to the repair portion, which needs its own price in your records.

  Source: N.C. General Statutes 105-164.4H, real property contracts

• The state's own example is a trades job: a $29,000 contract for a new roof, a new HVAC unit and a $290 toilet repair. With a Form E-589CI from the owner, the whole job is a capital improvement and none of the receipts are taxed.

  Source: NCDOR, Sales and Use Tax Bulletins, January 2026

• On a real property contract you are the consumer of everything you install. The supplier charges you tax on the unit, pipe and wire. If it did not, you owe use tax directly to the state and must keep records showing it was paid.

  Source: NCDOR, Sales and Use Tax Bulletins, January 2026

• A real property contractor shall not separately state any amount for tax on an invoice for a real property contract. Any tax shown is an erroneous collection and must be remitted to the state, on top of the tax you already paid on the equipment.

  Source: N.C. General Statutes 105-164.4H, real property contracts

• On taxable repair work you are a retailer. Parts that will be billed to the customer can be bought tax free for resale with Form E-595E. Items not resold owe use tax.

  Source: Form E-595E, Streamlined Sales and Use Tax Certificate of Exemption

• Service contracts, including maintenance agreements, tune-up plans and memberships, are taxable at the full state plus county rate, and the tax is due when the plan is sold, not per visit. The exemption for contracts on equipment attached to a building ended on March 1, 2016.

  Source: NCDOR, Service Contracts

• Plumbing and heating: the State Board of Examiners of Plumbing, Heating and Fire Sprinkler Contractors issues P-I (plumbing, any building), P-II (single-family only), H-1 (boilers and hydronic), H-2 (ducted systems over 15 tons) and H-3 (ducted systems of 15 tons and under, which covers most residential HVAC companies). Fuel piping is included in the plumbing and heating licences.

  Source: NC State Board of Examiners of Plumbing, Heating and Fire Sprinkler Contractors, applicant information

• A contractor licence needs two years, 4,000 hours, of on-site full-time experience, of which up to 2,000 hours may be technical training.

  Source: NC State Board of Examiners of Plumbing, Heating and Fire Sprinkler Contractors, applicant information

• All plumbing and heating licences expire on December 31 each year with no grace period; late renewal adds $25. No continuing education is required; the Board eliminated it in 2012.

  Source: NC plumbing and heating board, licence renewal

• Electrical: the State Board of Examiners of Electrical Contractors issues Limited (projects up to $60,000, $100 a year), Intermediate (up to $150,000, $150 a year) and Unlimited (any value, $200 a year). Intermediate and Unlimited need a bonding ability statement.

  Source: NC State Board of Examiners of Electrical Contractors, licensing

• Special restricted class SP-PH, Plumbing, Heating and Air Conditioning, lets an HVAC or plumbing firm do the limited electrical work tied to its own installations, $100 a year.

  Source: NC State Board of Examiners of Electrical Contractors, licensing

• Electrical licences run July 1 to June 30. Limited, Intermediate and Unlimited need eight hours of continuing education a year, at least half in a classroom; special restricted classes need four.

  Source: NC electrical board, continuing education

North Carolina has very warm, humid summers and moderately cold winters, so HVAC shops see a long cooling season from roughly May to September and a real but shorter heating season, longer in the mountain counties. The coast adds a second rhythm: a hurricane reaches the state about once every three years, and the storms drive generator, electrical, plumbing and HVAC replacement work from mid-August to late October.

• Summer weather is driven by the Bermuda High, which brings moist air inland and frequent thunderstorms. Winters are moderated by the Appalachians, and statewide winter averages have been mostly above normal since 1990.

  Source: NOAA NCICS, North Carolina State Climate Summary

• Hurricane season runs June 1 to November 30, with the peak from mid-August to late October.

  Source: ReadyNC, hurricanes

1. 1Tax on a full system replacementA central AC, furnace or whole-ductwork replacement is a capital improvement. Tax collected on it must be sent to the state, and you also paid tax on the equipment. We set the invoice so a system replacement carries no tax line and an E-589CI is on file.
2. 2Water heaters and part swaps as capital improvementsWater heaters, including tank to tankless, compressors, coils, breakers, outlets and fixtures are taxable repairs even when a permit is pulled. Tax is due on parts and labor. We map each service item to the state's chart.
3. 3Untaxed maintenance plansTune-up plans and memberships on equipment attached to a building have been taxable since March 1, 2016, with the tax due when the plan is sold. Shops that bill plans monthly often never charge it.