How to write an HVAC invoice

Name each visit, repair, part and pound of refrigerant, credit every payment already made, and give a firm due date.

Lines to bill and their units

Line	Unit	How it’s counted
HVAC labor	hr	Time on site, per technician
Diagnostic or service call	visit	One per trip
Flat-rate repair	job	One price per named repair
Parts	ea	Each part, with its part number
Refrigerant	lb	Pounds added, by type
Equipment	ea	Make, model and serial number
Maintenance visit	visit	Each visit the plan includes
Permit	ea	Fee and permit number

Name each repair after the component and the unit it serves, such as “Replace blower motor, attic air handler”, not “AC repair”. Refrigerant gets its own line with the type and pounds added, for example R-410A, 2 lb, so the customer sees what the charge was for. When the diagnostic fee counts toward the repair, show it as a credit so nobody thinks it was paid twice.

Deposits and payments already made

Show the full contract price, list each payment received with its date, and bill only the difference. As a round-number illustration: on a $10,000 contract with a $1,000 deposit and a $4,000 progress payment, the final invoice shows $10,000, $5,000 paid and $5,000 due.

Repair calls, installs and maintenance plans

Bill a repair call when the work is finished, before you leave if you can. An installation billed in stages follows the contract’s payment schedule: name the stage each invoice covers, such as equipment delivered or startup complete, and show the running total billed. A maintenance plan gets one invoice per billing period or per visit, as the plan sets, listing the visits covered; a repair found on a plan visit goes on its own line.

Due dates and payment terms

Set the terms when you book the job and print the due date as a calendar date, with the payment methods you accept. Commercial customers and property managers often pay through accounts payable, so ask before the first invoice what they need on it, such as a PO number, the site address or the unit number.

Sales tax on HVAC invoices

States differ on whether HVAC labor, equipment and parts are taxable, and installing a new system can be taxed differently from repairing an old one. Keep labor, equipment and parts on separate lines so each can be treated the way your state treats it. Add tax only where your state requires you to charge it, and check your state’s guide before you do.

EPA refrigerant records: which appliances they cover

Two EPA rules call for a service record when refrigerant is added or removed, and each covers only certain appliances:

• Ozone-depleting refrigerants: the rule applies only to appliances with a full charge of 50 or more pounds of a class I or class II refrigerant, or of a blend containing one, and not to appliances containing solely substitute refrigerants (40 CFR 82.157).
• HFCs and their substitutes: the rule applies to appliances with a full charge of 15 or more pounds of refrigerant containing a regulated substance or a substitute for one with a global warming potential above 53. It leaves out appliances used for residential and light commercial air conditioning and heat pumps, and appliances containing solely an ozone-depleting refrigerant (40 CFR 84.106).

On a covered appliance, whoever adds or removes refrigerant must give the owner or operator documentation when the job is done. If you service an appliance you don’t own or operate, the record shows the appliance’s identity and location, the date, the parts worked on, the type of work on each part, the name of the person who did it, and the amount and type of refrigerant added, or removed on disposal. Showing the type and pounds on every invoice is good practice anyway.

What some states require on HVAC paperwork

A few examples, not a full list:

• Texas: TDLR’s penalty schedule for air conditioning and refrigeration contractors lists as violations failing to provide an invoice to the consumer, leaving the license number or the company name, address and phone number off a proposal or invoice, and leaving the Department’s information off a proposal, invoice, contract or sign in the place of business (TDLR). The rule behind the schedule, 16 TAC §75.71(i), gives that information as the statement “Regulated by The Texas Department of Licensing and Regulation, P.O. Box 12157, Austin, Texas 78711, 1-800-803-9202, 512-463-6599,” followed by TDLR’s website address (16 TAC §75.71(i)).
• License numbers: California requires a licensed contractor’s number in all construction contracts, subcontracts and calls for bid (B&P §7030.5); Florida, a registration or certification number in every offer of services, business proposal, bid and contract (Fla. Stat. §489.119); Pennsylvania, for home improvement priced over $500 at a private residence, the registration number of a contractor under the state’s Home Improvement Consumer Protection Act (one whose home improvements reached $5,000 in the previous tax year) on its contracts, estimates and proposals with owners (73 P.S. §517.6). Print it on invoices too, and every document carries it.

Three mistakes that delay payment

1. “Recharge system” as one line. Without the refrigerant type and pounds, the customer can’t tell what they bought, and a return visit for the same leak starts an argument.
2. An unexplained diagnostic fee. If it was credited to the repair, show the credit; if it wasn’t, the customer should have heard that before you started.
3. Parts swapped in without asking. A contactor that wasn’t on the approved quote is the line the customer questions, so write it up with its price and get a signature before you install it.