When Do I Go Through Customs?
 

Hi,

I'm flying to Vancouver soon with the following flight path:

EWR -> PHL -> YYZ -> YVR.

I was wondering at what point will I go through Canadian Customs?

The Toronto Airport's website (https://www.torontopearson.com/Connecting.aspx#) said that I would be going through customs in Toronto, but my flight to Toronto and leaving Toronto are in the same Terminal. Do I really have to leave the terminal to go through customs and then have to wait in line to get back in?

I know the Toronto to Vancouver flight is a domestic flight so I wasn't sure at what point the customs comes into play.

Thank you

You will go though customs when you arrive in Toronto. It is in the same terminal building that you arrive in but you will have to go through security again before going to your departing gate. The website you provided is pretty clear, as is the airport signage.