In Canada the criminal limit is 80 mg of alcohol in 100 mL of blood — 0.08% — and it is set federally by the Criminal Code, so it is the same in every province and territory. What varies by province is the administrative layer that starts lower, at 50 mg (0.05%), and takes your licence at the roadside without any criminal charge.

Two things about the federal offence surprise most drivers, and both are in the statute rather than in the folklore around it.

You can be charged below 0.08

Section 320.14(1) creates more than one offence. Paragraph (b) is the familiar numeric one, but paragraph (a) makes it an offence to operate a conveyance while your ability to operate it is impaired to any degree by alcohol or a drug.

That paragraph contains no number at all. A BAC below 0.08 is not a defence to it; it simply means the Crown has to prove impairment by other evidence rather than by a breath reading. Any chart implying that 0.02% or 0.05% is "legal" in the criminal sense is describing paragraph (b) and quietly ignoring paragraph (a).

The clock runs for two hours after you stop driving

Paragraph 320.14(1)(b) does not ask what your BAC was while you were driving. It asks whether, within two hours after ceasing to operate a conveyance, you had a BAC equal to or exceeding 80 mg per 100 mL.

That wording is deliberate. It closed the old "I drank after I parked" defence. Section 320.14(5) leaves a narrow exception, and it is narrow: it applies only if you drank after you stopped driving, and you had no reasonable expectation of being required to give a sample, and your consumption is consistent with the reading. All three, not any one.

Federal penalties

These are minimums set by section 320.19, not typical outcomes. A court cannot go below them.

Situation Minimum penalty (first offence)
BAC 80–119 mg (0.08–0.119%) $1,000 fine
BAC 120–159 mg (0.12–0.159%) $1,500 fine
BAC 160 mg or more (0.16%+) $2,000 fine
Refusing to provide a sample $2,000 fine
Second offence 30 days imprisonment
Third or subsequent offence 120 days imprisonment

Note where the escalation points actually fall. The Code steps up at 120 mg and 160 mg — there is no 0.15 threshold in Canadian law, despite how often that figure appears in guides. And refusing the test carries a higher minimum fine than blowing over: $2,000 against $1,000. Refusal is not the cautious option.

On top of any fine, section 320.24 makes a driving prohibition mandatory, not discretionary:

  • first offence — one to three years;
  • second offence — two to ten years;
  • third or subsequent — at least three years.

Each of those runs on top of the entire period of any prison sentence. The maximum on indictment is ten years' imprisonment; on summary conviction, a $5,000 fine or two years less a day.

The provincial layer: suspended without being charged

Below the criminal limit, provinces run their own roadside suspensions. This is where the "warn range" lives, and it is genuinely separate: the officer suspends your licence on the spot, and no criminal charge needs to follow.

We have read Ontario's statute directly, so here it is in detail as the worked example.

Under section 48 of the Highway Traffic Act, a screening device that registers "Warn" or "Alert", or 50 mg or more per 100 mL, lets the officer demand your licence on the spot. Section 48(14) sets what follows:

Ontario roadside suspension Length
First7 days
Second14 days
Third or subsequent30 days

If you have seen "three days" quoted for a first Ontario suspension, that figure is out of date: it was raised to seven days by an amendment in 2024. Suspensions more than ten years old are not counted when deciding whether the current one is a first or a second.

The other provinces run comparable but not identical schemes, with different suspension lengths, penalties and impoundment rules — and at least one province does not operate a 0.05 warn range for fully licensed drivers at all. We have not read those statutes in their own registers, so rather than print a table that looks precise and is not, we would point you to your provincial transport ministry for the local figures. The federal numbers above apply everywhere regardless.

Zero tolerance for young and novice drivers

Ontario's Highway Traffic Act section 44.1 makes it a condition of the licence of every novice driver (G1 and G2) and every young driver that their blood alcohol concentration be zero while driving.

The Act defines a young driver as one under 22 years old — not under 21, which is the American threshold and is frequently misapplied to Canada. The two categories overlap but are not the same: a 25-year-old on a G2 licence is a novice driver and still held to zero.

Other provinces have their own zero-tolerance categories, commonly covering novice and young drivers and often commercial drivers, with the qualifying ages set provincially.

How many drinks is too many?

There is no answer that holds for two different people. What you reach depends on your weight, your sex, how long ago you drank, what you ate, and the actual strength of what was poured — a generous glass at home is not a standard drink.

The more useful point is structural: because paragraph 320.14(1)(a) has no threshold and the provincial warn range starts at 0.05, the space between "one drink" and "consequences" is much narrower than the 0.08 figure suggests. If you want an estimate for your own body, our BAC calculator will give you one — as an approximation, never as a substitute for not driving.

Official sources