Originally Posted by Rare

Ah, but did you read the question carefully, and are you sure the answer to that question is no? You are, of course, correct that only NEXUS members are allowed to use the NEXUS lane going into Canada. But zmb is asking whether, as an approved NEXUS member but before they receive the NEXUS card, they can use their existing Trusted Traveler card going into Canada. The idea is that if the card contains only an index into the Trusted Traveler database (possibly the PASSID number, which doesn't change), and the database record seen by the officer is what matters, then the officer should be able to see that they are, in fact, a NEXUS member. I don't know the answer--would be surprised if anyone here does, actually--but the question is more nuanced than it appears at first glance.