A new entry requirement, Electronic Travel Authorization (eTA), will be introduced by Citizenship and Immigration Canada in the coming months. Starting August 1, 2015, travelers will be able to apply for an eTA online. eTA will be mandatory for visa-exempt foreign nationals to gain entry into Canada beginning March 15,2016. Certain international travelers, who do not normally need a visa to enter Canada, will need to get an eTA before entering the country via air. There are some exceptions, for example,
“U.S. citizens do not need an eTA or a visa. However, proper identification must be presented at the border.
U.S. permanent residents need to get an eTA to fly to Canada.”
There is a list of eTA-required countries.
“What is an eTA
eTA is a new entry requirement for visa-exempt foreign nationals travelling to Canada by air. It will allow Canada to screen travellers before they arrive. The authorization is electronically linked to your passport and is valid for five years or until your passport expires, whichever comes first.”
Source: Electronic Travel Authorization (eTA) – Citizenship and Immigration Canada