100% tell them from the beginning. Tell them ahead of time if there's a way (if you're talking via email or anything, it's easy - "btw, I should let you know that I stutter. It doesn't interfere with my work, but I wanted you to know before we speak".) I would use your stutter as proof you'll do a good job. Sat something like "Look, just applying here was hard because of my speech, but I'm doing it because I really want the job. I'll work hard and do it right. This isn't something I take lightly." If the manager cares at all about their employees, they'll see the truth in that and be more than happy to hire you. Oh, and they can't choose not to hire you because of your stutter. That's literally illegal. I know interviews are awful when you're young and anxious about your stutter. (They're not great when you're older and more confident, but they do get a lot better) Remember that you're going up against applicants that don't really want to be there or won't put forth the effort to do well. You will. And the manager will see that. Good Luck.