a little background about the question, born and raised in the USA, i own a house that keeps me in the states and a full time job in the states. I am a triple citizen: USA, Hungary, and Canada. For reasons that might be obvious to some of you I do not have a Canadian passport. My USA passport is in for renewal and a buddy of mine in Vancouver BC wants me to assist in chauffeuring some mutual friends of ours who are coming in from Sweden up to Vancouver B.C. from Seattle for the weekend. I only have my Hungarian passport to help with this request. what are some issues i might encounter? do you think this is a good idea? As a well traveled person I understand how this looks to the border guard. it looks fishy. what say you all?
Hungarian citizens do not need a visa for Canada. You could therefore choose to enter Canada as a Hungarian and ignore your US citizenship. It is not necessary to mention it to the border guards unless they ask. You will need an eTA if you are arriving by air after March of next year.
US citizens do not always need a passport to travel to Canada. A birth certificate or certificate of citizenship or naturalization will work instead.
A much more interesting question is getting back to the US. While it will get you into Canada, a US birth certificate will not technically get you back into the US. If you have an Enhanced Drivers License (which IS acceptable) then present that on your return. However, as other questions have shown on this site, if you can prove you are a US citizen, (which a birth certificate should do) border patrol cannot exclude you from the US. The worst they can do is to give you a talking to about how you should really carry a passport. It is not permitted to use your Hungarian passport to enter the US (though again, if you can prove you are a US citizen I don't believe they can keep you out)
Based on Department Of State website,
Most U.S. nationals, including dual nationals, must use a U.S. passport to enter and leave the United States. Dual nationals may also be required by the foreign country to use its passport to enter and leave that country. Use of the foreign passport does not endanger U.S. nationality. Most countries permit a person to renounce or otherwise lose nationality.
passport-cardmight be an option, if you have it and you are crossing the border over land.