Q: Can I log into an American phone with a Canadian apple ID?

Hi madilo21,

It sounds like you are need to sign into your phone purchased in the US with your Canadian Apple ID. It should be fine and work without issue, but the country associated with your account must be the same as where you are physically located. If needed, you can change the country information with this article:

Change your iTunes Store country or region

Keep this info in mind:

When you change your iTunes Store country:

• You need to update your billing address to one in your new country. When you change your billing address, the primary address in your account at My Apple ID and your other Apple services, such as the App Store and iCloud, automatically updates.
• You might need to update your payment method. For example, only German credit cards can be used to buy content from the German iTunes Store and App Store.
• You won't see the items that you purchased from the previous country’s store in your Purchased section.
• You won’t see the items from your iCloud Music Library that you matched, uploaded, or added from the previous country’s store.

When you make a purchase in the iTunes Store, App Store, iBooks Store, or Mac App Store, the country in your iTunes Store account information must match the country listed in your account at My Apple ID.

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