How often should you moisturize? Once at the start of your day and again in the evening is the common wisdom—and you shouldn't be aiming for less! But this, like many other things, depends on your skin's particular needs and also how often you wash your face. Ideally, consider applying moisturizer anytime you wash your face. So if you wash your face after returning home from a midday grocery trip, that is a perfect moment to apply a layer of moisturizer to keep the skin from drying out.