Rules for re-entry into the U.S. depend on whether you are a U.S. citizen, a Canadian or citizen of a country on the Visa Waiver Program, or a non-U.S. citizen holding a temporary or long-stay visa. Prepare all necessary documents before traveling to Canada, and be prepared to present any goods acquired during your visit to U.S. Customs.

U.S. Citizens

U.S. citizens and permanent residents traveling to Canada by air are required by U.S. law to present a passport for entry into Canada and will need to present their passport again when re-entering the U.S. For those traveling by land or water, you will need a passport, passport card, NEXUS card, Enhanced Drivers License, or another Western Hemisphere Travel Initiative-compliant document to enter Canada, and will need to show these documents again to return to the U.S.

Non-U.S. Citizens

Citizens from countries that do not require a visa for travel to the U.S., including Canada and countries in the Visa Waiver Program, will need to present their passport for re-entry. Canadian citizens may also present their NEXUS card instead. Those holding non-immigrant visas, allowing them temporary visitation to the U.S., as well as long-stay visas, will need to present their visas along with their passport. All non-U.S. citizens must complete an I-94 form when arriving at the U.S. port of entry.

Expired U.S. Nonimmigrant Visas

If you're a non-U.S. citizen holding a non-immigrant travel visa that has expired at the time of re-entry into the U.S., Customs and Border Protection has certain requirements to allow you to return. First, you must have been in Canada for 30 days or less and only in Canada. Second, you must have a valid, unexpired admission stamp or a current I-94 form or card stating your approved visitor status. Finally, you cannot be from countries on the U.S. state-sponsored terrorist list.

Clearing Customs

When returning to the U.S. from Canada, all travelers are required to declare at customs any items purchased or acquired during their stay. This includes items received as a gift or bought as a gift for someone else, items purchased in duty-free shops, personal items bought during your stay, repairs to items you already own, and items you intend to sell. If the total of these items is less than a certain amount, you will be exempt from paying taxes, or duty, on them.