Impaired Driving in Ontario: Laws and Consequences
Last reviewed: 2026 · Driviology Road Safety Education Team
Quick Answer
Driving with a blood alcohol concentration (BAC) of 0.08 or higher, or while impaired by alcohol or drugs to any degree, is a criminal offence in Canada with immediate licence suspension and escalating penalties.
Impaired driving remains one of the leading causes of serious and fatal collisions in Ontario. The law treats it seriously at every level, from short roadside suspensions for a small amount of alcohol to criminal charges for higher BAC readings or drug impairment.
Ontario’s Escalating Penalties
| BAC / Situation | Typical Consequence |
|---|---|
| Warn range (0.05–0.079) | Immediate roadside licence suspension, escalating in length for repeat occurrences |
| 0.08 or higher, or refusal to test | Criminal charge, licence suspension, possible vehicle impoundment |
| Zero-tolerance drivers (G1/G2, under 21) | Any detectable alcohol results in a roadside suspension |
Zero Tolerance for Novice and Young Drivers
Drivers in the G1 or G2 stage of Ontario’s graduated licensing system, and all drivers under 21 regardless of licence class, must have zero blood alcohol while driving. Even a small, legal-for-others amount of alcohol can trigger a licence suspension. Learn more in our parent’s guide to young drivers.
Consequences Beyond the Law
Beyond fines and licence suspension, an impaired driving conviction can mean a criminal record, sharply higher insurance premiums, and in serious cases, jail time. Choosing a designated driver, rideshare, or transit option is always the safer alternative.