A medium sized white butterfly with a small black patch on the tips of the fore-wings, and black spots in the centre of the fore-wings, more pronounced in the female and sometimes hardly discernible in the male. These black markings are more pronounced in both sexes in the second generation. The hind-wings have a dark smudge on the leading edge. The underside of the wings have yellow tips on the forewings, and the under rear wing is a creamy yellow all over, with only the faintest vein markings.
The Small White can be seen on the wing very early in April and through May; the second generation fly in June and July, and a third generation in August and September.