How old do you have to be to have microdermabrasions?

No Age Limit. There is no age limit in performing the procedure.
Any age. This is done for very superficial irregularities. If you don't expect much of a change you won't be disappointed.
Minors need consent. Microderm is beneficial for acne prone skin so technically could be beneficial for patients who have acne which can appear as young as 10 or 11 (usually occurs with onset of puberty). It would be safe to perform but minors need to have the consent of their parents in order to have the procedure performed.