If we're going to be exact
Skyservice were the first North American A330 operator, with their ex-LTU A330-300
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Photo © Gary Gentle
Look at the titles on the aircraft in this photo.
Next was Canada 3000 with their -200s, Air Transat with their -200s, and next Air Canada with their -300s.
If things had gone to plan however, TWA, Northwest and Continental should all have introduced A330/340 fleets years ago, but that, as they say, is another stoty...