3 Invoice Examples for HVAC Businesses [+ Common Payment Terms]

An invoice template is a must-have for any business, but especially for a home service company. Find invoice examples for HVAC, electrical, and plumbing in this article. Make sure you don't miss any crucial info!
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Johnny O'Malley
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October 16, 2025

An invoice template is a must-have for any business, but especially for a home service company. HVAC businesses, plumbers, electricians, and more can benefit from having a simple, straightforward invoice template.

In this brief article, we’ll answer:

  • Why do we need an invoice template?
  • What should be included in an invoice template?
    • Invoice Example 1: The Basic HVAC Invoice Template
    • Invoice Example 2: The HVAC Installation Invoice Template
    • Invoice Example 3: The HVAC Maintenance Invoice Template
  • Plumbing invoice example template
  • Electrical invoice example template
  • What are the most common payment terms for field service businesses?
  • Next Step

If you’re just wanting the standard invoice template, you can click here to download it now and adapt it to your specific business needs.

Why do we need an invoice template?

You need an invoice template so you can make money faster and your front office staff don’t want to pull out their hair every working day.

Chances are, if you’re just starting your HVAC business, you’re probably looking for the best template you can find to make your job of invoicing customers easier and cleaner. You want to look more professional than a basic Microsoft Word invoice template.

Chances are, if you’ve been in business for more than 3 months, you already have some sort of invoice template, but perhaps you’re on the search for a new one because it’s not efficient or you find yourself needing to customize it all of the time.

I’m sure you’ve seen plenty of generic invoice templates in your day. They probably look like this:

  • Your business name in the top left corner
  • Your clients name in the top right corner
  • Line items of the work done in the middle (# of items, description, price per unit, total)
  • A number of days to pay it in
  • And a generic, thank you for your business at the bottom

Honestly, there hasn’t been much innovation in the invoices over the last 50+ years because there hasn’t had to be.

But we don’t live in a paper age anymore, we live in a digital age. And it’s cumbersome to have to type in each line item, the description, the price, and then tally it all up at the end to make sure you invoice the customer the proper amount.

Let’s get your HVAC business into the 2020s, into the digital age, so you can skip the time-sucking, brain-numbing activity of filling in each invoice in a Word template or Excel template.

Whether you’re an owner, technician, or front office staff – whether you’re in HVAC, plumbing, electrical, or another home service line of work – you need this invoice template in your toolbelt.

What should be included in an invoice template?

An invoice template should include more than what I listed above. In a nutshell, it should clearly outline the work completed by the company and the amount owed by the client and when it is due.

Broadly speaking, you need to answer the who, what, when, where, why, and how questions.

And more importantly, you need to handle these digitally. Send the invoice digitally, reminders to pay the invoice digitally, and accept payment digitally.

We’ll look at three distinct invoice examples below:

Invoice Example 1: The Basic HVAC Invoice Template

More specifically, when looking at a basic HVAC invoice, you need to include the following guidelines as you write up the invoice:

  • Header: company name, logo, contact info
  • Billing Information of the Customer: customer name, address, contact details
  • Itemized List: the HVAC services provided, such as installation, repairs, maintenance along with the quantity, unit prices, total amount for each service
  • Subtotals: display the subtotal of all services and work performed
  • Taxes and Fees: include any applicable state or local taxes, fees, etc.
  • Total Amount Due: Show the final to be paid by the customer
    • Make this crystal clear and in a box or bolded by itself again, after the initial table
  • Payment Terms: Outline the payment due date, accepted payment methods, and any additional instructions
    • Regarding payment due date: give a deadline! Otherwise, you aren’t going to get paid.
    • Define the penalty for paying late. When does it go into effect? Is it a flat fee or a percentage of existing bill? Does it accrue?
    • Regarding accepted payment methods: don’t make it difficult to pay you! Make it a crystal clear button or box on your form. Can a customer pay via an online portal? Or just by logging into a site? That’s a necessity post 2020.
    • But if you’re not set-up that way yet, tell them exactly where they can pay you and using what methods– credit card, check, ACH, etc., phone number, at your place of business, etc.
    • If they need support and have questions, make it easy too. If they’re struggling to pay online, how can a customer reach you? Again, is it via phone, email, chat, form on your site, etc?
  • Reaffirm your commitment to them as the customer.

Once you’ve accounted for these questions, and have a rough draft ready, review the document with your team to make sure no edits are needed. After making edits, get final approval with your leadership team. It may even be worthwhile to have it approved by legal counsel before eventually rolling it out to customers.

Invoice Example 2: The HVAC Installation Invoice Template

There’s another type of HVAC invoice template, usually specific for HVAC installation.

It includes similar items, but a couple additional unique ones:

  • Header
  • Billing Information
  • Itemized List
  • Subtotals
  • Taxes and Fees
  • Total Amount Due
  • Payment Terms
  • Reaffirm Your Commitment

Then it also includes:

  • Details of the itemized list of the equipment installed: air-conditioning unit, heating system, ventilation components, along with prices and quantities of each
  • Labor Charges: how many hours of labor, at what rate per hour
  • Warranty Information: this may be on the invoice itself, if you warranty it as the field service company. Or, it may be a separate packet of information attached that comes courtesy of the manufacturer of the HVAC equipment

Don’t forget the labor charges, obviously, or you’ll be working for free! And don’t forget the warranty information because customers really care about that.

Invoice Example 3: The HVAC Maintenance Invoice Template

This includes the same information as the basic HVAC invoice template, but it’s also wise to include additional information like:

  • A copy of the maintenance contract
  • The maintenance agreement number
  • The specific maintenance services provided, so customers can see you did more than just walk around and look at a thing
    • Specific inspections of different pieces of equipment
    • Filter replacements
    • Cleaning items
    • Tune-ups or activation of units
  • Notes of any units or potential problems ahead (aka if their furnace is 28 years old and you know they usually go out between 25-30 years)

Basically, with a maintenance invoice template, you want to show that you did worthy work and assure your customer that doing these things is important and a proactive investment.

Communicate honestly with your customers, post-maintenance appointment, to let them know where replacements may be needed soon. That way, if something does go out, they know risks ahead of time. And if they’re smart, they’ll start to budget for it.

Many apps for contractors will have invoice templates built in. The good ones will integrate directly with Quickbooks to make your accounting and financial systems (and taxes) even easier too.

Warranty information and maintenance records no longer need to be printed and stored in some folder in a massive file cabinet that sits in your office and takes up space.

Instead, it’s all kept digitally, in the software, in the cloud.

You can bring it all up when you type a customer’s name, “John Doe,” in the database. Every invoice, every piece of equipment, every location (if handling a multi-site business) could be attached to the same record. It’s truly that simple!

The Challenge of Invoicing for Maintenance

A lot of people don’t want to pay for maintenance, then complain when something goes out and you can’t get to them the day of their calamity.

But you, as an HVAC owner, know the importance of maintenance. So, try to communicate that in a reasonable way to customers. You’ll have the relationship with them and know what resonates with them, but just putting yourself in their shoes and asking questions like:

In the shoes of a homeowner: Would you rather not do maintenance, wait until something breaks, and then be out of heat for 3 days in the freezing winter until we can get to you? Or would you rather pay $250 for a HVAC system check from a professional, have all new filters, and not have to worry?

Or, if you’re servicing a fellow company owner, you can ask: Would you rather not do maintenance, wait until the boiler goes out, then have to shut down production for 72 hours, make no money, and have to eat a ton of overhead costs? Or pay $1K to have it all checked, proactively serviced, and not have to worry?

You know the people you service and how to best get through to them. But if customers aren’t giving maintenance the thought and attention they should, you may need to help them see the value of it.

It’s money for you; it’s peace of mind for all.

Plumbing invoice example template

To make a plumbing invoice template, include the following basic information:

  • Header
  • Billing Information
  • Itemized List
  • Subtotals
  • Taxes and Fees
  • Total Amount Due
  • Payment Terms
  • Reaffirm Your Commitment

For installation invoices, the itemized list section should include materials, supplies, units, as well as labor and warranty information.

For maintenance invoices, include:

  • A copy of the maintenance contract
  • The maintenance agreement number
  • The specific maintenance services provided, so customers can see you did more than just walk around and look at a thing
    • Specific inspections of different pieces of equipment
    • Filter replacements
    • Cleaning items
    • Tune-ups or activation of units
  • Notes of any units or potential problems ahead  

Electrical invoice example template

To make an electrical invoice template, include the following basic information:

  • Header
  • Billing Information
  • Itemized List
  • Subtotals
  • Taxes and Fees
  • Total Amount Due
  • Payment Terms
  • Reaffirm Your Commitment

For installation invoices, the itemized list section should include materials, supplies, units, as well as labor and warranty information.

For maintenance invoices, include:

  • A copy of the maintenance contract
  • The maintenance agreement number
  • The specific maintenance services provided, so customers can see you did more than just walk around and look at a thing
    • Specific inspections of different pieces of equipment
    • Filter replacements
    • Cleaning items
    • Tune-ups or activation of units
  • Notes of any units or potential problems ahead  

What are the most common payment terms for field service businesses?

The most common payment terms for field services in various industries, including home services, HVAC, plumbing, electrical, and more include:

  • Net 30
  • Net 15
  • Due on Receipt
  • 50% Deposit, Balance Due on Completion
  • Progress Payments
  • Retainer Fee
  • Installment Payments
  • Prepay / Upfront Payment

Thankfully, most job management softwares have done the hard work for you.

They allow your technicians to collect payment directly from customers in the field.

They integrate with Quickbooks or other accounting software.

They might also make it possible to select any one of these payment term options, so you can select that you use as a business, or you can customize to different size jobs, for different customers.

Basically, you can have it your way, per individual invoice.

Next Step

Click on the box below and you can start to write your own invoice template.

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Johnny O'Malley
Johnny O'Malley is a seasoned field service business owner. He started with the tool belt on, over 35 years ago. He eventually went out on his own and grew from a single man operation to a 9-figure plumbing business. Johnny regularly shares insights on emerging trends, workforce development, and service excellence. He has a passion for mentoring other owners and leaders and helping them grow into pillars for their community.