During a 12-year study of the Barn Owl Tyto alba I investigated the short- and long-term fitness correlates of hatching date, brood size and hatching rank. Observations showed that nestling survival was lower at the end of the breeding season and in larger broods, and that chicks born late in a /, hatching sequence died more often than their older siblings. Survivors also developed longer tarsi in larger broods and when positioned at the top of the within brood size hierarchy. Pairs breeding earlier in the season and producing larger broods more often recruited at least one of their offspring in the local breeding population. I did not detect any association between the reproductive success of yearling recruits and birth date, the size of the brood out of which they fledged, and their within-brood hatching rank. This study therefore lends support for the prediction that the rearing conditions experienced by nestlings are rather more strongly correlated with fitness 1 components expressed early than later in life.