Documents

• Anyone who wishes to cross the U.S.-to-Canada border must have proof of citizenship and proof of identity. For U.S. citizens, this includes a passport, passport card, NEXUS card or a combination of a government-issued ID along with a birth certificate, naturalization certificate or expired passport. For non-U.S. citizens, this includes their passport and green card, if applicable.
  
  

Duration

• Each crossing into Canada has a set duration. This is determined at the discretion of the border officer, who writes or stamps the date into your passport. The maximum stay in Canada as a visitor is six months; however, it is possible to convert from a visitor's stamp or visa to several types of visa while in Canada to extend your stay.
  
  

Working

• Working in Canada after a border crossing is illegal, unless you have already obtained the proper visa. It is possible to extend your stay to work, study or live in Canada, but you need to file an application with the Citizenship and Immigration Canada office to do so. If you work illegally in Canada while on a visit visa, Canada may prevent your from ever returning to Canada again.
  
  

Children

• Children traveling with their parents to Canada also require identification. Those who are under 16 need to present proof of U.S. citizenship, such as a birth certificate, naturalization certificate or passport. If a child is not traveling with her parents or a parent with full, legal custody, a notarized affidavit of consent from the child's parent(s) may be required.
  
  

Air Travel

• Air travel has different restrictions. All U.S. citizens must provide a valid U.S. passport for re-entry into the United States when traveling by air. Passport cards and NEXUS cards are not acceptable for air routes. Foreign nationals and lawful, permanent residents must present their valid passport, visa or green card to re-enter the U.S.