The stamp has to be accepted where you mail the letter. If you are mailing in Canada, you need a Canadian stamp. If you are in the US mailing to Canada, you can use a US stamp.
That is what you do with a stamp, put it on a letter to pay for it to be delivered. You always use the postage from the country you are mailing the item in.
Have to use postage from country of origin
Yes, that is what stamps are for, to pay postage from the US to anyplace else in the world, regardless of the country. A standard letter would cost 72 cents.
What is the cost of a letter to be mailed from US to Canada
Yes, that is how it works. You buy the postage at the US post office and apply it to the envelope. The currently the cost is 75 cents.
Any US Postage stamp with a denomination on it is valid for international mail. You cannot use the Letter Series (A through H series) that don't have a number on them.
No, you can't. You should go to your local U.S. post office and purchase a Canadian stamp to mail your letter.
You must use Canadian postage stamps when you are mailing a letter from Vancouver, BC, Canada. You would need to purchase a certain stamp depending on the letter's destination. Postage rates apply to domestic, USA, and International destinations.
You use the postage of the country of origin, in this case, you would use Canadian postage.
If you are posting it in the US, yes. As long as the amount on the stamp covers the overseas postal charge.
Yes. Every letter mailed in the US needs a stamp.