Canadian citizens are not required to obtain United States consular visa stamps in their passports for entry into the United States. Instead of a visa stamp, Canadian citizens are currently admitted to the United States by presenting proof of Canadian citizenship*, and all documentation required for their visa status. See the required documentation for international travel here.

*Important new rule: citizens of Mexico, Canada, and Bermuda would be required to have passports (or if they are Canadian, Air NEXUS cards) when entering the United States by air as of January 23, 2007, and sea or land border crossings by January 1, 2008.

For more details about this topic go to http://travel.state.gov/travel/cbpmc/cbpmc_2223.html.