I read my post and I found I should clarify... CBP did not automatically send GE cards to those who had GE before cards are issued. I actually paid another $15 (IIRC) for the GE card.

I checked my GOES account, my approval letter says this:

"We are pleased to inform you that your U. S. Customs and Border Protection (CBP), Global Entry program membership has been approved. You can begin using the program immediately."

The card is only inactive until you activate it for security reasons. If someone steals your mail they don't want some random person having a valid card to enter the country with (I believe the GE card is valid to enter the country in a SENTRI/NEXUS lane)

But, back to the original question, until you get the approval notification the KTN won't work.

I was told at the interview that it was valid immediately, though I didn't need it for some time so didn't test that.

My take is that we really have two different aspects of the GE program and the associated KTN going on here. Once you go through the interview, assuming no issues arise, the agent does tell you that the KTN in now ready to use for PreCheck. The GE aspect doesn't kick in until you receive your GE card and go through the activation process. As for trying to use the assigned KTN before going through the interview......probably won't work but probably wouldn't do any harm either. Can't imagine that TSA/DHS has the resources or even the inclination to try to track down erroneous or even fake KTN input. Between folks fat-fingering the wrong numbers or transposing numbers there are probably too many for them to worry about.

The GE part works with a passport but, of course, you can't use the card until you receive and activate it. I did the interview outbound and used GE with a passport inbound a few days later. The card didn't come for a few more days.

Yes, because you passed the interview. You usually get the approval notice right after the interview.

It's not valid before you show up to the interview.

Which was the original question way upthread. I was clarifying the comment about it not being valid until you activated the card.

To clarify
 

As this thread has gone a bit awry

OP asked if he/she could use the KTN before the interview. I think the general answer is no.

Known Traveller ID
 

Can I use my KTN before I've completed the interview? Flying out next week but interview not until after I return. thanks!

If you mean for global entry, I doubt it since you're not approve until after you pass the interview.

Yes, it's through GOES program. I've been "conditionally" approved. Just wondering whether it would cause problems if I entered the number into my United account profile for my current tix.

You can add it into your profile but it won'tbe active so you won't get precheck until after you're approved.

Conditionally approved simply means that you are approved for an interview. The # won't be useful until after the interview and you are notified that you have been approved. That can happen as soon as minutes after your interview or you could be denied.

I would recommend against entering the number anywhere until you have been approved. It certainly won't result in anything good such as Pre-Check. Whether it results in anything "bad" us unknown.

Membership #/PassID question
 

Hello, my GE interview is scheduled for 2/24 and I just went into my application to see if an earlier date had popped up that worked in my scheduled and noticed I've been assigned a membership #/PASSID. Will this number be my KTN once my application is finally approved?

If yes, is it safe to start placing this number in my different airline profiles? I have 4 trips coming up starting 3/3.

Thanks!

Yes, it is your Known Traveler Number. You can add this KTN to your airline profiles. For existing reservations, it is best to add to your reservations. Please see these two thread; https://www.flyertalk.com/forum/showthread.php?t=1873378&referrerid=22732 and https://www.flyertalk.com/forum/showthread.php?t=1568890&referrerid=22732