These Top-Rated Vitamin-C Serums Will Have You Looking on the Bright Side of Dull Skin

If you use — and love — niacinamide for dark spots already, or have been wanting to add this to a skincare rotation, the IT Cosmetics Bye Bye Dark Spots 4% Niacinamide Serum ($29) features that ingredient plus vitamin C for a double dose of dark-spot lightening power. It's got an average 4.6 star rating from other Sephora shoppers whether using it for age spots, melasma, or another type of discoloration.