It really depends on what is in your toner. If your toner contains a lot of alcohols and astringents, then it’s not a good idea to tone too often. It also depends on how strong the active ingredients in your toner are. In general it should not really be necessary to tone more than twice a day unless you are on a specific program/regime that requires you to wash your face and re-apply all your product mid-day as well, then MAX three times a day.