GST/HST Reverse Calculator

Work backward from a tax-included total to find the pre-tax price — useful when you know what a customer paid but need to know the amount before GST, HST, or PST/QST was added. Enter the total and select the province, and this tool applies that province's exact tax rate to pull out the tax-included and pre-tax amounts, along with the tax breakdown itself. You can't just subtract a flat percentage from the total, since the tax rate applies to the pre-tax amount, not the total — this tool does the actual reverse calculation for you, using the current 2026 rates for every Canadian province and territory.

This tool provides estimates only and is not a substitute for professional advice — see our Terms of Service for details.