*Updated April 2015
Each airline has its own checked baggage allowance, and the list of links below will direct you to their specific webpages. Note that the free checked baggage allowance will differ depending on where you are flying from, your destination, and even the fare level you purchased. For example, Air Canada usually allows one normal size piece of luggage checked for free, sometimes two, while other airlines charge a fee even for one bag.
Some US carriers charge for each and every checked piece, and what seemed like a great deal turns out to be more than you expected. If you are flying on a charter flight to a sunny destination, the normal baggage allowance is usually one piece totaling no more than 20kg. Most flights to Europe or Asia from Canada allow one piece as well. One normal sized suitcase, provided it is not packed with heavy items, will weigh approximately this amount.
Excess baggage charges are punitive. Some airlines charge $5 per kg over, others up to $40 per kg, and others have odd tariffs such as a percentage of the full economy fare per unit of weight in excess.
Bottom line, if you are traveling with more than a normal sized suitcase, with normal weight of clothes, you need to check the baggage restrictions carefully.
The size of your baggage also matters, not the weight. Many airlines have a size principle where the length, depth, and height cannot exceed a specified amount, or a total amount of all three. Again, if you have anything other than a normal sized suitcase, it’s important to check this in advance. Some airlines are very stringent with this, and you will see people re-packing on the floor at checkin, or throwing articles out to meet the weight and size restrictions.
Here are quick links to the baggage allowance and restrictions pages for each airline:
Full list of airline baggage allowance: