This study examines the extent to which a study abroad (SA) experience has an effect on the L2 written and oral performance of a group of Spanish undergraduates, studying English as a second language (L2) in a university in the UK. This article also examines the role that individual differences, such as the participants' motivation, attitudes, perception of progress, L2 contact and academic factors, have with regards to their written and oral performance. Written and oral data were collected from 24 participants by means of a composition and an oral narrative before and after their overseas experience, whereas data on individual differences were gathered through a questionnaire. The results of the statistical analyses suggest that SA is positive for L2 development, particularly for oral skills. Results also indicate that some individual differences related to the participants' attitudes, university degrees, self-perception of their L2 proficiency and L2 contact play a role when learning an L2 abroad. (Contains 1 table.)