If you don't have one, you won't be able to board your flight.
However, there are alternative options for providing appropriate contact information. Here is what you can do if you do not have a point of contact in the US: Hotel contact details: If you have already booked accommodation, you can provide the contact details of the hotel where you will be staying in the USA.
This is the Government of Canada's official web page to apply for an electronic travel authorization (eTA) to fly to, or transit through, a Canadian airport. It only costs CAN$7. Find out what it is and how to apply online.
The Department of Homeland Security recommends that travel authorization applications be submitted at least 72 hours prior to travel.
ESTA applications may be submitted at any time prior to travel. The processing of an ESTA can take up to 72 hours. It is also advisable to check the status of an already approved ESTA in advance of traveling to make sure that it is still valid.
A Travel Authorization (TE) is used to request approval for a business-related trip. In this document, the traveler indicates trip destination(s), purpose, and dates of travel and requests advance checks. In response, the TE records trip information and schedules advance checks.
Most applicants get their eTA approval (via an email) within minutes. However, some requests can take several days to process if you're asked to submit supporting documents.