Ontario has three blood alcohol thresholds: 0.08 (80 mg/100 mL) is the criminal limit; 0.05 to 0.079 is the warn range, triggering administrative licence suspensions; and 0.00 applies to all novice (G1/G2) drivers and anyone under 21. Exceeding any threshold carries serious consequences.
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The Three Blood Alcohol Thresholds
Ontario law recognizes three distinct blood alcohol concentration (BAC) levels, each carrying different consequences.
| BAC Level | Who It Applies To | Consequence |
|---|---|---|
| 0.00 (zero) | G1, G2 drivers; anyone under 21 | Immediate 3-day licence suspension (first); 7-day (second); 30-day (third+) |
| 0.05-0.079 (warn range) | All drivers | Administrative suspension: 3 days (first), 7 days (second), 30 days (third+) |
| 0.08+ (criminal) | All drivers | Criminal charge, 90-day immediate suspension, vehicle impound, possible imprisonment |
Zero Tolerance for Novice Drivers and Under 21
If you hold a G1 or G2 licence, or if you are under 21 years old regardless of licence class, you must have a blood alcohol concentration of exactly zero. Even one drink can put you over. A roadside breath test showing any alcohol triggers an immediate three-day licence suspension for a first offence.
Warn Range Consequences (0.05-0.079)
The warn range is not a criminal offence, but the administrative penalties are severe. A first warn-range stop results in a 3-day licence suspension. A second within 5 years results in a 7-day suspension plus a mandatory alcohol education program. A third or subsequent offence within 5 years results in a 30-day suspension, an alcohol treatment program, and an ignition interlock condition when your licence is reinstated.
Criminal Impaired Driving (0.08+)
Being caught at or above 0.08 BAC is a criminal offence under the federal Criminal Code of Canada. Consequences include an immediate 90-day roadside licence suspension, vehicle impoundment for 7 days, a mandatory minimum $1,000 fine for a first offence, and a criminal record. Repeat offences carry escalating jail time. A criminal impaired driving conviction can affect employment, travel to the United States, and your ability to obtain insurance.
Drugs and Driving
Ontario's zero tolerance for drugs also applies to novice drivers. For all drivers, being impaired by cannabis, prescription medication, or illegal drugs is a criminal offence. Drug recognition evaluators can demand a saliva or blood sample at the roadside. There is no safe level of THC defined by law for driving.
Related Questions
What Is the BAC Limit for Novice Drivers in Ontario?
Novice drivers in Ontario (G1 and G2 licence holders) must maintain a blood alcohol concentration of exactly zero while driving. Ontario also applies zero tolerance to all drivers under the age of 21, regardless of licence class.
Read answerWhat Is Distracted Driving in Ontario?
Distracted driving in Ontario includes using a hand-held mobile device, texting, eating, grooming, reading, or programming a hand-held GPS while driving. Ontario has some of the strictest distracted driving laws in Canada. First-time offenders face a fine of up to $1,000, 3 demerit points, and a 3-day licence suspension.
Read answerWhat Are the Restrictions on a G2 Licence in Ontario?
G2 drivers must maintain a zero blood alcohol level (0.00 BAC), ensure all passengers wear seatbelts, and avoid handheld electronic devices. Drivers age 19 or under also face passenger limits between midnight and 5 AM. These restrictions remain until you pass the full G road test.
Read answerWhat Are the Rules for School Buses in Ontario?
In Ontario, you must stop when a school bus has its red lights flashing and its stop arm extended, regardless of which direction you are travelling. The only exception is if the bus is stopped on the opposite side of a divided highway with a raised median. Fines range from $400 to $2,000 and carry six demerit points.
Read answerCan You Drive at Night with a G2 Licence in Ontario?
Yes, G2 drivers can drive at night in Ontario. There is no curfew or nighttime driving ban for G2 licence holders. The only night-related restriction applies to G2 drivers age 19 or under in their first 6 months: they may carry only 1 passenger aged 19 or under between midnight and 5 AM.
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