How do I remove 14.975% tax from a total in Quebec?

Divide by 1.14975. A $100.00 total is $86.98 before tax and $13.02 of tax. Subtracting 14.975% from the total instead gives $85.02, which is wrong by $1.95.

Why is subtracting the percentage wrong?

Because the tax was calculated on the pre-tax price, not on the total. Taking 14.975% off the total removes 14.975% of a bigger number than the one the tax was worked out on, so you take away too much. The error is proportional and grows with the receipt.

Do I reverse the GST and the QST one at a time?

No. Both were charged on the same pre-tax price, so you reverse them together with one division by 1.14975. Undoing them in sequence assumes a compounding that never happened and gives $86.60 instead of $86.98.

Does this work for a receipt with exempt items on it?

No, and that is the real limitation. If part of the bill was zero-rated — groceries, prescriptions — the tax was charged on only part of the total, and dividing the whole thing gives the wrong split. This works for a receipt where everything was taxable.

2026 · QC · 14.975% to remove

Reverse sales tax calculator, Quebec

A $100.00 receipt in Quebec is $86.98 before tax and $13.02 of tax. You get there by dividing by 1.14975 — not by taking 14.975% off the total.

Written and edited by Pablo Ruiz QuinteroSources checked September 1, 2026Rates read off the CRA and Revenu Québec on 2026-09-07

Rates 2026Where QuebecRuns in your browser

Total you were charged

Quebec charges 9.975% QST beside the 5% GST — an odd rate with a real history, and one that is calculated on the price excluding the GST, not on top of it.

Price before tax

$86.98

from $100.00 charged

The breakdown
Price before tax	$86.98
GST 5%	$4.35
QST 9.975%	$8.68
Total	$100.00

Combined rate 14.975%. The QST and the GST are both charged on the price before tax — neither is calculated on top of the other.

Why you cannot just subtract 14.975%

You have a receipt for $100.00 in Quebec and you need the price before tax. The instinct is to take 14.975% off the total. That gives $85.02, and it is wrong by $1.95.

The reason is that the tax was never calculated on $100.00. It was calculated on the smaller number — the pre-tax price — and then added. So to undo it you divide by 1.14975, not subtract a percentage. The right answer is $86.98 before tax and $13.02 of tax.

The error is proportional, so it grows with the receipt: on $10,000 it is $195.04. It is the single most common arithmetic mistake in expense claims, and it always goes the same way — understating the pre-tax cost, and therefore the tax you could claim back.

When you actually need this

Expense claims and bookkeeping. A business reclaims the GST/HST it paid as an input tax credit, and to do that it needs the tax split out. A till receipt that only shows a total forces the calculation.

Invoicing backwards from a round number. Quoting "$1,000 all in" means the price before tax is $869.75, not $1,000. Get that wrong on a quote and the difference comes out of your margin.

Checking a receipt. Dividing the total and comparing the tax line is the fastest way to spot a till charging the wrong rate — which happens most often in the months after a rate change.

The arithmetic, in full

For Quebec, with a combined rate of 14.975%:

Price before tax = total ÷ 1.14975

GST = price before tax × 0.05 · QST = price before tax × 0.09975

Worked on $100.00: $100.00 ÷ 1.14975 = $86.98, of which $4.35 GST and $8.68 QST.

Note that both taxes come off the same base. Reversing them one at a time — dividing by 1.05 and then by 1.09975 — would be undoing a compounding that never happened, and gives $86.60 instead of $86.98.

Where to go next

Quebec sales tax calculatorThe same tool adding tax instead of removing it.Reverse tax anywhere in CanadaAll thirteen jurisdictions.Quebec income tax calculatorThe other half of what this province takes.

Questions

How do I remove 14.975% tax from a total in Quebec?: Divide by 1.14975. A $100.00 total is $86.98 before tax and $13.02 of tax. Subtracting 14.975% from the total instead gives $85.02, which is wrong by $1.95.
Why is subtracting the percentage wrong?: Because the tax was calculated on the pre-tax price, not on the total. Taking 14.975% off the total removes 14.975% of a bigger number than the one the tax was worked out on, so you take away too much. The error is proportional and grows with the receipt.
Do I reverse the GST and the QST one at a time?: No. Both were charged on the same pre-tax price, so you reverse them together with one division by 1.14975. Undoing them in sequence assumes a compounding that never happened and gives $86.60 instead of $86.98.
Does this work for a receipt with exempt items on it?: No, and that is the real limitation. If part of the bill was zero-rated — groceries, prescriptions — the tax was charged on only part of the total, and dividing the whole thing gives the wrong split. This works for a receipt where everything was taxable.