Atlantic chub mackerel (Scomber colias) is a middle size pelagic species distributed on both sides of the Atlantic Ocean. Landings of this species have increased recently in the Iberian Peninsula, likely associated to the increase of its abundance and expansion northwards, probably related to an increment of the sea temperature. The aim of this study is to improve the knowledge of the reproductive biology of the Atlantic chub mackerel and to present updated information on spawning period and maturity ogives that can be used for analytical stock assessment in ICES and its management.