Timelines vary widely. No one on the internet can tell you whether you got the job, how long things will take, or whether an e-mail would be perceived as obnoxious. Do not waste time trying to read the tea leaves (e.g., "Hmm, they said 'we will let you know'...is that a good sign?"); this is fruitless. You should continue your job search until you have accepted a written offer.
Can I inquire about the status of my application?
…if I have another offer?
If you have another offer on the table and need to make a decision soon, it is absolutely appropriate to contact all departments where you have had a full interview (also known as an on-campus interview), tell them that you have such an offer, and ask about the status of your application.
…if I do not have another offer?
As stated here, this is pretty similar to habanero sauce: use it judiciously, and very sparingly, and it's often best not to use it at all. In particular, "demonstrating interest" will not make much difference at this level. If you do inquire, it's very unlikely that they will reply "Oh! Didn't we tell you? Yes, you're hired." Rather, you will almost certainly get an inconclusive answer, no answer, or a negative answer.
Still, If you were told to expect a response by a particular day, it is probably reasonable to follow up a week after the deadline. If you were not given any timeline, then following up a month after your last communication is likely appropriate. Your mail should be clearly-written and concise; there is really no need for this mail to be longer than a sentence or two.
But why haven't I heard anything?
As written in this answer, there are three likely reasons that you haven't heard anything:
- They don't want to hire you, but forgot to tell you.
- They have offered the job to someone else, but are keeping you around as a backup in case the first person turns them down.
- They are still interviewing candidates (or have encountered other delays), and won't decide for a while.
It's therefore unlikely that you'll get a useful answer just by asking (unless you're in case #1, in which case you'll get the bad news).
Especially in Europe during the summer break, many faculty members will be on vacation and do not answer their email (or only select emails) and it can take longer than expected to hear back from them. Sending multiple emails will not help in this case.
What's the typical timeline?
Varies from days from many months.
- For US faculty positions, interviews are often held over a few months. It can then take much longer for a decision to be made and finalized such that the candidate can be contacted.
- For UK faculty positions, interviews are generally held with all candidates in just a few days. Even so, decision timelines can range widely.
- For most post-docs, and also for European graduate admissions, decisions are made by a single professor. But even here, interviews may be scheduled over several months, and the professor may be waiting for funding awards or for other factors outside their control. And so, timelines can still vary widely.
- For US graduate admissions, most decisions are made between mid-January and mid-April. If you haven't heard anything by mid-March, it's probably not good news, but some students do get admitted later, even after the April 15 deadline.
What can I do to improve my odds?
Not much. After you complete the application process, there is nothing to do except check your e-mail. Sending frequent follow-ups is unlikely to impress anyone, and will probably come across as desperate. Don't try any "tricks" like asking for additional interviews, setting arbitrary deadlines, or contacting HR; these will hurt more than they help. On the other hand, if you have real "news" that affects your candidacy (such as a reduced timeline due to a competing offer or a new source of external funding), it's appropriate to share this.
At what point do I give up and assume I've been rejected?
As above, there is no real answer to this. If you haven't heard anything after several months and your requests for updates have gone unanswered, then your prospects are indeed bleak. And yet, we cannot say that your odds are zero. But in any case, it does not really matter; you should never assume that you have a job until you've accepted a written offer.
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