The aim of this study was to determine if preterm birth is associated with socioeconomic status (SES), psychological functioning, and health-related quality of life (HRQoL) in adulthood. We used prospective follow-up of 192 adult offspring of mothers who took part in a randomized controlled trial of antenatal betamethasone for the prevention of neonatal respiratory distress syndrome (66 born at term [33 males, 33 females] 126 born preterm [66 males, 60 females]). Cognitive functioning was assessed using the Wechsler Abbreviated Scale of Intelligence. Working memory and attention was assessed using the Benton Visual Retention Test, the Paced Auditory Serial Addition Test, and the Brown Attention Deficit Disorder Scale. Psychiatric morbidity was assessed using the Beck Depression Inventory II, the State-Trait Anxiety Inventory, and the Schizotypy Traits Questionnaire. Handedness was assessed using the Edinburgh Handedness Inventory. HRQoL was assessed using the Short Form-36 Health Survey. Moderately preterm birth (median gestation 34wks, mean birthweight 1946g [SD 463g]) was not related to later marital status, educational attainment, SES, cognitive functioning, working memory, attention, or symptoms of anxiety or schizotypy at 31 years of age. Preterm birth was associated with fewer symptoms of depression and higher levels of satisfaction in three of the eight HRQoL domains measured (bodily pain, general health perception, and social functioning). Adults who were born moderately preterm have SES, psychological functioning, and HRQoL consistent with those who were born at term. This good long-term outcome cannot be extrapolated to those with early childhood disability or very low birthweights.