GST/HST for Ontario Contractors: Registration, Invoices and Input Tax Credits

If you work as a contractor, subcontractor or trades business in Ontario, GST/HST affects more than the amount you add to an invoice. It also affects how you record customer payments, track business expenses, claim Input Tax Credits (ITCs) and prepare your GST/HST return.

Understanding these requirements can help you avoid common bookkeeping problems and keep your records organized.

This guide explains the key GST/HST considerations for Ontario contractors in plain language.

1. When does an Ontario contractor need to register for GST/HST?

The general small-supplier threshold is $30,000 in taxable supplies. The calculation generally considers taxable supplies made by you and relevant associated persons, subject to CRA rules.

The timing depends on how you cross the threshold.

If you exceed $30,000 in a single calendar quarter

You generally stop being a small supplier on the supply that causes you to exceed the threshold.

You must begin charging GST/HST on that supply and register according to CRA requirements. The effective date of registration is no later than the day of the supply that caused you to exceed the threshold.

If you exceed $30,000 over four consecutive calendar quarters

If you exceed the threshold across four consecutive calendar quarters but do not exceed it in a single quarter, the timing is different.

Generally, you stop being a small supplier at the end of the month following the quarter in which you exceeded the threshold. You must begin charging GST/HST on your first taxable supply after that date and register within the applicable CRA deadline.

Important: Do not rely only on your bank deposits or the amount of profit you earned. Monitor taxable supplies and apply the CRA threshold rules to your business.

Some contractors may choose to register voluntarily before they are required to. Voluntary registration can allow eligible ITC claims, but it also brings GST/HST collection, filing and recordkeeping responsibilities.

2. What GST/HST rate should contractors charge?

Ontario's general HST rate is 13% for taxable supplies subject to the Ontario rate.

However, the rate depends on the type of supply and the place-of-supply rules. Contractors working across provincial borders should not automatically apply Ontario's rate to every job.

For example, a contractor may need to consider where the service is supplied and the applicable GST/HST rules when working for customers in another province.

Before issuing an invoice, confirm:

• Whether the supply is taxable

• Where the supply is considered made

• Which GST/HST rate applies

• Whether the customer is being charged tax separately or the quoted amount includes tax

3. What should a contractor include on a GST/HST invoice?

A contractor's invoice should clearly explain the work performed and the amount charged.

For taxable supplies, customers should be able to understand whether GST/HST is included in the price or added separately.

Depending on the transaction and the customer's circumstances, CRA requires specific invoice information to support the customer's ITC claim.

Your invoice process should include:

• Your business name and contact information

• Customer name and address, where required

• Invoice number and date

• Description of the work performed

• Amount charged before GST/HST

• Applicable GST/HST rate

• GST/HST amount or a clear statement that tax is included

• Total amount payable

• Your GST/HST registration number when required

For invoices of $100 or more, suppliers generally need to provide their GST/HST account number. Additional documentary requirements apply depending on the invoice amount.

If your customer is a GST/HST registrant, make sure the invoice contains the information they need to support their ITC claim.

4. Can contractors claim Input Tax Credits?

Registered businesses may be eligible to recover GST/HST paid or payable on purchases and expenses used in their commercial activities.

This is done through Input Tax Credits, commonly called ITCs.

Depending on the facts, common contractor expenses may include:

• Construction materials and supplies

• Tools and equipment

• Fuel and vehicle expenses

• Repairs and maintenance

• Business insurance and professional fees

• Telephone and office expenses

• Eligible subcontractor costs

However, not every expense qualifies for a full ITC.

The expense must meet the applicable GST/HST requirements. Personal use, exempt activities, restrictions and documentation can affect the amount you may claim.

Keep the right supporting documents

Before claiming an ITC, make sure you have appropriate supporting documentation.

For larger purchases, the information required can include the supplier's name and address, GST/HST registration number, invoice date, description of the supply, amount paid or payable, and GST/HST amount.

If you hire subcontractors, review their invoices and confirm their GST/HST registration where appropriate.

A supplier's invoice should not automatically be treated as proof that the GST/HST charged is eligible for an ITC.

5. Common GST/HST bookkeeping mistakes

Contractors can run into problems when GST/HST is not tracked separately from business income and expenses.

Common issues include:

Recording HST collected as revenue

The HST collected from customers is generally not your business revenue. It should be tracked separately so you can reconcile the amount collected with the GST/HST return.

Claiming ITCs without adequate documents

A bank statement showing a payment may not contain all the information required to support an ITC.

Keep the supplier invoice, receipt or other acceptable documentation.

Missing subcontractor invoices

Subcontractor costs should be recorded with appropriate supporting documents. Check whether GST/HST was charged and whether the supplier's registration details are available.

Mixing personal and business expenses

If an expense includes personal use, the ITC may need to be restricted or adjusted.

Not reconciling GST/HST accounts

Your bookkeeping should reconcile GST/HST collected, eligible ITCs, adjustments and amounts paid or refunded.

A reconciliation helps identify differences before the return is filed.

6. How should contractors organize GST/HST records?

Keep your bookkeeping organized throughout the year instead of waiting until the filing deadline.

A practical monthly process is:

1. Record customer invoices and payments.

2. Record supplier invoices and business expenses.

3. Collect receipts and supporting documents.

4. Review subcontractor invoices.

5. Reconcile bank and credit-card transactions.

6. Review GST/HST collected and ITCs.

7. Investigate differences before filing.

CRA generally requires businesses to retain GST/HST records and supporting documents for six years from the end of the year to which they relate, subject to exceptions.

Keep invoices, receipts, contracts, accounting records and copies of filed returns in an organized and accessible format.

7. When should a contractor get GST/HST bookkeeping help?

Professional support may be useful if:

• You are approaching the $30,000 registration threshold.

• You are unsure when to start charging HST.

• Your invoices do not clearly show GST/HST.

• You have missing receipts or subcontractor documents.

• Your bookkeeping does not reconcile to your GST/HST return.

• You have several projects, employees or subcontractors.

• You need help preparing and filing GST/HST returns.

Good bookkeeping can help you understand what you collected, what you may be eligible to claim and what needs to be remitted.

GST/HST support for Ontario contractors

CPA Charanpreet Singh provides accounting, bookkeeping and tax support for contractors and small businesses in Ontario.

If you need help with GST/HST registration, bookkeeping cleanup, ITC review, reconciliation or return preparation, contact us to discuss your situation.

Request GST/HST bookkeeping and compliance support:
[Insert the relevant service page or consultation link]

This article provides general information and is not individualized tax advice. GST/HST treatment depends on the facts of each transaction and the applicable CRA rules. Consult a qualified professional about your specific circumstances.

Frequently asked questions

Do Ontario contractors charge 13% HST?
Ontario's general HST rate is 13% for taxable supplies subject to the Ontario rate. Place-of-supply rules and the nature of the supply should be considered.

Can a contractor register voluntarily?
A small supplier may generally choose to register if eligible. Registration brings collection, filing and recordkeeping obligations, and may permit eligible ITC claims.

Can I claim HST on tools and materials?
You may be eligible to claim ITCs on GST/HST paid or payable for purchases used in commercial activities, subject to the applicable rules and supporting documentation.

Can I claim an ITC if I only have a bank statement?
A bank statement may not provide all the information required. Keep the supplier invoice or other appropriate supporting documentation.

How long should I keep GST/HST records?
Generally, six years from the end of the year to which the records relate, subject to CRA exceptions.

Do subcontractors need to provide their GST/HST number?
Where required, the supplier's GST/HST account number should be included on invoices or other supporting documents. You can use CRA's GST/HST Registry to confirm registration details.

The blog is for information purpose only, it is not a legal advice. For your business-specific questions, contact CPA Charanpreet Singh to discuss GST/HST bookkeeping and compliance support. Here is our Contractor Page.

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