Which passport do you use when travelling to non eu country?

I was just wondering what other dual citizens do when travelling to non EU countries? I am travelling to Canada and want to use my USA passport but don't know if since I am travelling direct from UK need to use the UK one? Any advice?

I would use the US one but I can't think of any reason for not using the UK one because they both limit your stay in Canada.

I'm not a British citizen but when I was in Ontario, Canadian customs inquired about 'my business' in the UK. I'm sure when you get there you can tell them that you are a dual UK/US citizen. As far as I know, you don't show them anything when you leave the country, at least in Canada.

I'm not a British citizen but when I was in Ontario, Canadian customs inquired about 'my business' in the UK. I'm sure when you get there you can tell them that you are a dual UK/US citizen. As far as I know, you don't show them anything when you leave the country, at least in Canada.

except if you are going to the US because the US authorities are in Canada??

except if you are going to the US because the US authorities are in Canada??

Never traveled to the US via Canada so I wouldn't know for sure, but when traveling to the US from the UK, I didn't show my US passport until I reached US customs in the US.

http://talk.uk-yankee.com/index.php?topic=61915.0

I'd use the US one to enter Canada, and the UK one to enter the UK and whichever passport or show both leaving Canada.