Travelling Outside Canada
You should have a valid Canadian passport for all trips outside Canada. A passport is the only reliable and universally accepted identification document, and it proves that you have a right to return to Canada.
Do I need a passport to travel to the United States?
You need a passport if you're flying into the U.S., as of January 23, 2007. If you're crossing by land or water, you will need to show valid identification, such as a government-issued ID plus a birth certificate or citizenship card. And sometime after June 2009, you'll need a valid passport, no matter how you enter the U.S.
For further information, consult the Public Safety and Emergency Preparedness Canada Web site
Planning to travel to Mexico from Canada?
Although the Government of Canada recommends that Canadians travelling to any destination outside of Canada carry a valid passport, it is not mandatory to do so for travel to Mexico. To date, there has been no policy change requiring Canadians to travel with their passports to this destination. However, you must have sufficient identification to satisfy border officials of your identity and citizenship.
It is recommended that you consult your travel agent or the embassy or consultate of Mexico in Canada for travel document requirements.
Even though a passport is not currently required for entry to the United States or Mexico, it is mandatory to obtain a passport if you are taking a cruise or travelling on to another country.
Transport Canada Regulations