How Do You Send a Letter From the United States to Canada?
Send a letter from the United States to Canada using the First-Class Mail International option provided by U.S. Postal Service. The cost of sending a letter to Canada is slightly more than sending it within the United States.
Address the letter
Address the letter to a destination in Canada. Include the appropriate postal code after the city, and write “Canada” on a separate line at the bottom of the address.
Weigh the letter
Place the letter on a postage scale. As of February 2015, only letters or flat envelopes weighing less than 4 pounds can be sent via First-Class Mail International.
Use adequate postage
Include enough postage to mail the letter to Canada. It is acceptable to use regular or international postage stamps or metered mail.
Mail the letter
Take the letter to a local post office, or drop it into a blue U.S. Postal Service mailbox.