Can I cross the US-Canada border with a Canadian passport and a US passport card as a dual citizen?

If you are a dual citizen then you would show proof of the citizenship of the country you are entering; in fact you must. So if you are entering Canada then you would produce an appropriate Canadian identity document. It need not be a passport and if you are entering the US then you would show, as preferred by the US, your passport. However, other documents are accepted to prove your citizenship.

The link provided lists the appropriate documents to use and when to use them for entry to Canada or the US.

You are confused, Adam, so let me explain this multiple passport thingi in more detail.

Generally speaking, a citizen of a country does always have to enter and to exit his country of citizenship with the proper passport, identifying him as a citizen of that country.

So if you are a citizen of country A and country B, you leave country A with passport A, then, when you get to the border of country B, you pull out passport B.

When you leave country B again, you again show passport B, and if you then return to the border of country A, you pull passport A out again.

Now, in case of USA and Canada we have an unusual constellation: the United States does not recognize multiple citizenship, but Canada does and even encourages it.

What that means is that as a citizen of the USA and Canada, you can exclusively travel with your US passport only, both ways. If the Canadian border patrol asks you, you have to "identify" yourself as a Canadian citizen, but you are not required to have a valid Canadian passport if you have another valid one, in this case from the US.

This does not work the other way around though.

Use the US card to enter the US. With the passport card no passport is required for

border entry. See this: https://help.cbp.gov/app/answers/detail/a_id/74/se...

They don't care..Just don't bring any explosives, firearms or fruit baskets.