HST Tax Calculator (Canada)
Use this tool to either add HST to a pre-tax amount or extract HST from a tax-included total.
Note: Rates may change. Confirm with the CRA or your provincial tax authority for official filing and invoicing requirements.
What is HST?
HST stands for Harmonized Sales Tax. In participating Canadian provinces, the federal Goods and Services Tax (GST) and provincial sales tax are combined into a single tax rate. For consumers, this usually means one tax line at checkout instead of multiple lines.
If you run a small business, invoice clients, or budget household purchases, a fast and accurate HST tax calculator helps you avoid math errors and keep records clean.
GST vs HST vs PST (quick breakdown)
- GST: Federal tax, currently 5%.
- HST: Combined federal + provincial tax in participating provinces (for example, 13% or 15%).
- PST/RST/QST: Provincial taxes collected separately in some provinces (not shown as HST).
Current HST rates used in this calculator
| Province / Region | Tax Type | Rate |
|---|---|---|
| Ontario | HST | 13% |
| New Brunswick | HST | 15% |
| Newfoundland and Labrador | HST | 15% |
| Nova Scotia | HST | 15% |
| Prince Edward Island | HST | 15% |
| AB, BC, MB, SK, NT, NU, YT | GST only option in this tool | 5% |
How to use this HST tax calculator
1) Add tax to a pre-tax amount
Use this when you know the base price and need the final amount charged to the customer. Example: product price is $100 before tax, and you want the tax amount and final total.
- Enter the pre-tax amount.
- Choose your province/rate.
- Select Add tax to pre-tax amount.
- Click Calculate.
2) Extract tax from a tax-included total
Use this when the total already includes HST and you need to separate tax from revenue. This is common for bookkeeping, reimbursements, and expense reports.
- Enter the tax-included amount.
- Choose your rate.
- Select Extract tax from tax-included total.
- Click Calculate.
Formulas behind the calculator
Adding HST
Tax = Pre-tax Amount × (Rate ÷ 100)
Total = Pre-tax Amount + Tax
Extracting HST
Pre-tax Amount = Total ÷ (1 + Rate ÷ 100)
Tax = Total − Pre-tax Amount
Practical examples
Example A: Ontario purchase
Pre-tax amount is $250.00 in Ontario (13% HST).
Tax = $32.50, Total = $282.50.
Example B: Tax-included receipt in Nova Scotia
Tax-included total is $115.00 with 15% HST.
Pre-tax amount = $100.00, Tax = $15.00.
Common mistakes to avoid
- Using the wrong province rate for the place of supply.
- Applying the add-tax formula when the total already includes tax.
- Rounding too early before final totals.
- Mixing GST-only provinces with HST provinces.
FAQ
Is this tool good for invoices?
Yes, for quick estimates and drafts. For official filings, always verify rates and rules with CRA guidance and your accountant.
Can I use a custom tax rate?
Yes. Select Custom rate and enter any value from 0% to 100%.
Does this calculator include PST or QST logic?
This page focuses on HST/GST-style single-rate calculations. If you need separate provincial taxes, use a dedicated GST+PST or GST+QST calculator.
Bottom line
A reliable HST calculator saves time, improves accuracy, and makes budgeting or invoicing easier. Whether you are a shopper, freelancer, or business owner, you can quickly calculate tax, totals, and tax breakdowns with confidence.