How long, on average, should you wait to follow up after an interview for a job at a supermarket?

Define “follow up”

If you mean to send a follow up to thank them for the interview then same day and up to two days later would be ideal.
If you mean to call and ask if they had made a decision yet, I’d give it a week.
Good luck!

^^^
Took the words right out of my…....uhh…....keyboard…...

I would say if you’re following-up on their decision I would make a polite, low-key phone call or send an email two weeks after your interview.

If you’re calling to see if you’ve gotten the job, I’d wait at least a week.

The day after and every day after that until you either land the job or it’s no longer available. It’ll show them how serious you are about the position.

^ Don’t follow this suggestion. You’ll just annoy the hell out of them and it will pretty much guarantee you won’t get the job. They may have had many applications and done a number of interviews. For my organization, there is a lengthy and complicated process HR have to go through before they contact a candidate and offer them a job. Be patient. Wait a week and then politely follow up.

@Earthbound_Misfit is exactly right. Calling every day will only make the decision-makers at your prospective employer roll their eyes, laugh about it on their coffee break, and wonder if you have all your marbles.

Hang back a little. They will respect and appreciate that…..

For an entry level position such as this, I would not even bother with a follow-up of the type that you’re thinking of – not at all. When people are being interviewed for these positions it’s because they are needed now. There isn’t the same lengthy hiring process that a professional would have to go through if they were hiring for, say, the store manager position. That one takes time to fill, and a lot of consideration of the various candidates’ good and bad points.

The position you want should be decided upon within a day of interviewing all of the various applicants. (There usually isn’t even a résumé requirement, just “fill out this application and talk to this person over here”.)

It would still be proper and courteous to send a thank-you letter, just because it is good manners, if for no other reason than that, but I wouldn’t bother with a follow-up call at all. Just go to your next best choice and go through their application process until you land the job you want.

Ideally, this is the kind of interview that you’ll have where the interviewer can shake your hand at the end and simply ask, “When can you start?” Aim for that job in this skill position. (Companies that are nimble enough to make those on-the-spot decisions are usually more enjoyable to work for, anyway.)

The above advice form @CWOTUS is the best you are going to get in this situation.

This “follow-up in writing” business only makes sense when you are applying for something more at the professional level. And early in the working-career of just about everyone, to just “keep going through the application process” is something that almost all of us has had to do.

A simple ‘thank-you’ note is respectful, and will make them remember you….but after that, I would just leave it alone.

The only constructive thing I can add to what @CWOTUS just said is…...

Follow your instincts before jumping on board with the first offer you receive…..

Every job I have inquired for I have gotten without fail. If you feel that your interview went well, I would show up at that establishment within 2–3 days. If it is a popular job they will have other people acquiring as well. Be a face that they will know, make this employer see you, so burnt into their head hard as they try they could not forget you. If there is an opening, fine, you’ll most likely get the job on the spot. Although, if there is not a job available or possibly an interviewing process, the employer will offer a call-back [as in your case]. Now, when a job becomes available, or its time for second interviews/“call-backs”[in your case], guess who’s name and face will pop into their head? The one they couldn’t forget. Go inside, introduce yourself again, couple days later again, then again….go there so much they will have to give you a job. They will have had enough of you coming in asking for one they WILL hire you. I have never needed to go in twice, but keep that in mind. Have the mindset to get this employer to KNOW YOU. Never fails. That is, if you really want this job…?