Contractor Invoice Template Ontario (Free)

Most contractor invoices in Ontario are missing at least one field that protects you legally. The CRA cares about HST. The Construction Act cares about what counts as a "proper invoice" so you actually get paid in 28 days. If your invoice is missing either, you are leaving money and leverage on the table.

This is a free contractor invoice template for Ontario, with every required field, the math for HST, and how the Prompt Payment rules change what you put on the bottom.

What a Contractor Invoice Must Include in Ontario

There are two sets of rules that matter: the CRA (federal, for HST) and the Ontario Construction Act (provincial, for getting paid on time). A contractor invoice template that ignores either is worse than no template.

CRA requirements (for invoices over $30 with HST)

The Canada Revenue Agency requires every invoice that includes HST to show:

Your business name and address
Your GST/HST registration number (the 9-digit BN plus RT0001)
Date of the invoice
Total amount paid or payable
Amount of HST charged, or a statement that HST is included and the rate (13% in Ontario)
Buyer name (for invoices over $150)
Brief description of the goods or services
Terms of payment (for invoices over $150)

If you are not registered for HST yet (under $30K in revenue over 4 quarters), you do not collect it and you do not show it. But the moment you cross $30K, you have 29 days to register. See the CRA HST registration rules.

Construction Act requirements (for "proper invoice" status)

Since October 2019, Ontario has had Prompt Payment rules under the Construction Act. To trigger the 28-day clock for getting paid, your invoice must qualify as a "proper invoice." That means it must include:

Contractor name and business address
Date of the invoice
Period during which the work was done
Description of the work (including materials supplied)
Amount payable for the work, broken down
Name, title, and contact information of the person to whom the invoice is being sent
Authority under which the work was done (your contract or work order reference)
Payment terms
Any other information required by your contract

Miss any of these and the owner can argue your invoice is not "proper" and the 28-day clock never starts. Get it right and you have legal grounds to charge interest, file a lien, or trigger adjudication if you are not paid.

Free Contractor Invoice Template

Copy this layout. Every section maps to a CRA or Construction Act requirement.

INVOICE

[Your Business Name]
[Street Address]
[City, ON, Postal Code]
HST #: 123456789 RT0001
[Phone]
[Email]

----------------------------------------

Bill To:                  Invoice #: 2026-042
[Client Name]             Date: April 13, 2026
[Client Address]          Due: May 11, 2026 (Net 28)
[City, ON, Postal Code]

Project: [Job description, e.g., "Bathroom renovation"]
Job Site: [Address if different from client]
Work Period: April 1 to April 12, 2026
Reference: Quote #Q-2026-018 / Contract dated March 25, 2026

----------------------------------------

DESCRIPTION                  QTY   RATE     AMOUNT

Labour
  Demo and prep              12 h  $85/h    $1,020.00
  Plumbing rough-in           8 h  $95/h      $760.00
  Tile installation          16 h  $85/h    $1,360.00

Materials
  Tile (subway, white)       80 sf  $4.50    $360.00
  Vanity (Home Depot)         1     $475     $475.00
  Plumbing fixtures           1 lot $640     $640.00
  Misc supplies               1 lot $185     $185.00

----------------------------------------

                              Subtotal    $4,800.00
                              HST (13%)     $624.00
                              ---------------------
                              Total       $5,424.00

Holdback (10%)                            -$542.40
                              ---------------------
Amount Due Now                            $4,881.60

----------------------------------------

Payment Terms: Net 28 days from receipt of this proper invoice,
as required under the Ontario Construction Act.

Late Payment: Interest at 2% per month (24% annually) on overdue
balances, compounded monthly.

Holdback: 10% statutory holdback retained per Ontario Construction
Act, released 60 days after substantial performance.

Payment Methods: e-Transfer to invoices@yourcompany.ca,
cheque payable to [Your Business Name].

Questions: Call [Your Name] at [Phone] within 7 days of receipt.

Section by Section: How to Fill It Out

Header (your business)

Use your legal business name, not a nickname. If you registered as "Smith Plumbing & Heating Ltd.", that goes here. If you are a sole proprietor, use your legal name plus your trade name. Your HST number is non-negotiable once you are registered.

Invoice number

Use a sequential, unique number for every invoice. The CRA can request this in an audit. Format suggestions:

2026-001, 2026-002 (year + sequence)
INV-04-001 (month + sequence)
JOB123-INV1 (job + invoice within job)

Whatever you pick, never reuse a number. Never skip numbers.

Bill to

Use the legal name of the person or company responsible for paying. For a homeowner, this is the person who signed the contract. For a commercial job, this is usually the company name plus the project manager you report to. The Construction Act requires "name, title, and contact information of the person to whom the invoice is being sent," so include the project manager line.

Work period and reference

Prompt Payment requires the period covered. Always include the date range. The reference line links the invoice back to the contract or quote, which is required for "proper invoice" status.

Line items

Separate labour from materials. Three reasons:

Some clients (especially commercial) want to see them split
Materials may be exempt from certain markups in negotiated contracts
If you ever need to defend the invoice in adjudication or small claims, the breakdown is your evidence

For labour, show hours and hourly rate. For materials, show quantity and unit price.

HST calculation

In Ontario, HST is 13%. Always charged on the subtotal of labour plus materials, never on holdback alone. If the client asks for an HST-exempt invoice, they need to give you a valid exemption certificate. Otherwise, charge it.

Holdback

For any contract over $25,000 lasting more than 30 days, the Ontario Construction Act requires a 10% statutory holdback. The owner retains 10% of every invoice until 60 days after substantial performance is published. You do not get this money until the holdback period expires and no liens are filed.

Show it on every invoice as a line item so the client expects it. See the Ontario Construction Act overview for the full rules.

Payment terms

Net 28 is the standard under Prompt Payment. You can offer faster terms (Net 15, Net 7) but you cannot legally enforce slower than 28 days from receipt of a proper invoice.

Late fees

The Construction Act allows interest at the rate set in your contract. If your contract is silent, the default is the prejudgment interest rate (currently around 5%). Most contractors charge 2% per month, which is legal as long as it is in your contract.

Ontario Prompt Payment Act: What Changed

Before 2019, contractors waited 60, 90, sometimes 120 days to get paid. Since the Construction Act amendments, the timeline is fixed:

Step	Days
Owner pays general contractor	28 days from proper invoice
GC pays subcontractor	7 days from receiving owner payment
Subcontractor pays sub-subcontractor	7 days from receiving payment

If the owner does not pay in 28 days, you can:

Charge interest immediately
Trigger adjudication (a fast-track dispute process, decision in ~30 days)
Register a construction lien against the property within 60 days of substantial performance

All of this only works if your invoice is "proper." That is why every field on the template above matters.

Common Invoice Mistakes That Cost You Money

Missing HST number. The CRA can refuse to allow your client to claim the input tax credit, and your client may withhold payment until you fix it.
No work period. Without dates, the invoice is not "proper" under the Construction Act and the 28-day clock never starts.
Lumping labour and materials. Some clients use this as an excuse to dispute the total. Always break it out.
Forgetting holdback. If you do not show the 10% holdback, clients sometimes refuse to release it later, claiming they already paid you in full.
No late fee clause. If your contract does not specify an interest rate, you are stuck with the prejudgment rate. Add 2% per month to your contract template and your invoice.
Skipping invoice numbers. CRA audits flag this fast. Use sequential numbers, no exceptions.

Going Digital

Word and Excel templates work for the first 10 invoices. After that, you are losing time on three fronts: re-entering client info, calculating HST manually, and tracking which invoices are paid versus overdue.

A proper invoicing tool does three things a template cannot:

Auto-numbers invoices so you never duplicate or skip
Calculates HST and holdback on every line
Tracks paid vs unpaid so you know who to follow up with this week

For a sense of where invoicing fits into the bigger picture of your contracting business, including pricing, job costing, and follow-up, take the Contractor Profit Score. It maps the seven dimensions where most contractors leak money, and invoicing is one of them.

You should also know your WSIB status before sending any invoice to a commercial client, since most general contractors will refuse to pay the final invoice without a current clearance certificate. Read WSIB Clearance Certificate Ontario: Complete Guide for the details.

A good invoice is not a piece of paper. It is the document that makes the difference between getting paid in 28 days and chasing a client for 6 months. Use the template above on every job. Update your contract to reference the Construction Act. And if you want the math, the tracking, and the follow-up automated, join the Grizzli waitlist for early access.