CBP encourages travelers to apply for a travel authorization at least 72 hours in advance of their anticipated arrival at a U.S. land port of entry. I am a citizen of Canada? No, citizens of Canada who are traveling with a Canadian passport do not need an ESTA.
Visa-exempt foreign nationals need an eTA to fly to or transit through a Canadian airport. These travellers do not need an eTA when arriving by car, bus, train or boat (including a cruise ship).
If you don't have one, you won't be able to board your flight.
An Electronic Travel Authorization (eTA) is an entry requirement for visa-exempt foreign nationals travelling to Canada by air. An eTA is electronically linked to a traveller's passport. It is valid for up to five years or until the passport expires, whichever comes first.
Who already have a visa in their passport. Travelers may wish to avoid buying plane tickets until they have obtained an ESTA (or a valid visa, in case the ESTA is not approved). ESTA applications may be submitted at any time prior to travel. The processing of an ESTA can take up to 72 hours.
In addition to your passport, you may need a travel authorization such as a visa or an Electronic Travel Authorization (eTA) to enter Canada. Consult Immigration, Refugees and Citizenship Canada's website to learn which authorization you need: Find out if you need a visa to travel to Canada.
An Electronic Travel Authorization (eTA) is an entry requirement for visa-exempt foreign nationals travelling to Canada by air. An eTA is electronically linked to a traveller's passport. It is valid for up to five years or until the passport expires, whichever comes first.
Entry into Canada: Canadian law requires that all persons entering Canada carry proof of citizenship and identity. A valid U.S. passport, passport card, or NEXUS card satisfies these requirements for U.S. citizens.
U.S. citizens are exempt from the eTA requirement and must carry proper identification such as a valid U.S. passport. Lawful permanent residents of the United States who hold valid status in the U.S. are exempt from the eTA requirement.