Early intervention aims to prevent poor literacy outcomes associated with social disadvantage. This study examined whether the short‐term positive effect of a preschool classroom‐based oral language and phonological awareness (PA) programme was maintained and transferred to literacy 2 years later. The vocabulary knowledge, grammatical skill, auditory comprehension and reading comprehension of 54 6–7‐year‐old Australian children who attended school in a low‐socioeconomic area were measured. Children's PA abilities were also assessed and are reported elsewhere. There were no significant differences between children who had received intervention in preschool and those who had not, with the entire cohort performing below the average range of the general population. The findings indicated that while generating short‐term positive effects, intervention in preschool did not enhance socially disadvantaged children's language and literacy achievement in the long term.