I was made a verbal offer for a job at a college, which I accepted over the phone. I haven't got the written offer and I have not signed anything yet. I was informed the written offer will be sent to me in a few days.
That evening, I received an interview e-mail from the same college but a different campus (which I prefer).
What should I do? Wait till I get a formal offer letter from the first campus and then let them know I need more time?
What is the wisest and the ethical course of action?
You're not under any contractual obligation (and don't have any legal recourse if the college were to withdraw the offer!) until you've gotten a written offer (which will normally have a deadline by which you must respond) and returned it with your signature. It's in your interest to continue pursuing other opportunities until the first institution has come through with a complete written offer and you've accepted it.
I would contact the second campus, explain that you would prefer to work there if you got an offer, but that you've already got an offer in hand (and what the deadline on that offer is, if you've been given one.) You need to know how rapidly the second campus will be able to conduct their interview and make an offer. If they couldn't possibly make an offer to you before the deadline on the first offer, then I would decline to interview and just take the first position. If it is possible for them to move quickly, then I'd suggest that you go ahead and interview.
There is a risk here- if the first institution finds out that you're interviewing elsewhere, they might decide to withdraw their offer. The only way to avoid this risk entirely is to turn down the second interview.
This is a tricky situation. The college won't take your oral acceptance as seriously as a written acceptance, but they may still take it seriously enough to screw things up for them and/or other candidates. For example, their second favorite candidate may be sitting on another offer while waiting to hear from this college. Your oral acceptance may lead them to tell this candidate that it's not worth really pushing to extend the deadline for the other offer.
For this reason, you shouldn't accept an offer, even just orally, unless you are really certain and committed. It's also not in your own interests to accept before all possible negotiations are finished, since your bargaining power decreases dramatically upon acceptance.
Given that you already accepted over the phone, the big question is how seriously they took it. If you had an elaborate discussion premised on the fact that you are joining them next year, then you really need to deal with this if you intend to keep interviewing elsewhere. For example, you could write something like "Thank you again for the offer, which I'm very excited by. I'm afraid that in my enthusiasm, I let the discussion of joining you next year get a little bit ahead of itself, and of course I'll have to discuss the details of the written offer with you before I officially reply." This is definitely awkward, but I don't think there's any non-awkward way of essentially retracting an oral acceptance. (Especially because you don't want to retract it so thoroughly that they lose interest and withdraw the offer.)
If your oral acceptance was more of a passing comment, without any involved discussion or evidence that they took it seriously, then it's a little less awkward. You could just write "Thank you again for the offer, which I'm very excited by. I'm looking forward to receiving the details. What is the deadline for my decision?" That would make it clear that you didn't consider the phone conversation a real decision. But this approach doesn't even acknowledge that your oral acceptance could be an issue, which is really awkward if they did take it seriously, so you should be careful.
Either way, clarity and honesty are the key principles. You don't want them to be taken aback or feel used if you keep interviewing or accept another offer instead.
Wait till I get a formal offer letter from the first campus and then let them know I need more time?
I'd recommend letting them know earlier than that, to minimize the chances that they will make any decisions based on your oral acceptance.
There's a risk that they could be offended and call the whole thing off, but I think this risk should be small if you handle it smoothly, and they could withdraw a written offer too (so getting it in writing won't protect you).
