The legal drinking age in Canada varies from province to province. All alcoholic drinks are restricted to those of or above the provincial legal drinking age.
In Alberta, Manitoba, and Québec the legal drinking age is 18 years. In the rest of Canada, the legal drinking age is 19 years.
Restaurants, bars and liquor stores all require two pieces of ID before they will sell you alcohol. One piece of ID must have your name, photograph, signature and date of birth, and be issued by an official agency (your passport would be a perfect example). The other must have your name and signature, and can include major credit cards. Without these two pieces of ID, you may be refused service.
Those caught drinking underage are subject to legal consequences. Police occasionally check on bars and restaurants to see if they are serving minors. Police also often stop drivers at random to test for drinking and driving, which is a serious offence under Canadian law. Canadians like to have fun, but it is important to enjoy your alcoholic beverages responsibly and legally while in Canada.