Objectives: To examine the contribution of early life factors and preschool- and school-aged language abilities to children's 11-year language and academic outcomes. Methods: Participants (N = 839) were from a prospective community cohort study of 1910 infants recruited at 8 to 10 months of age. Early life factors included a combination of child (prematurity, birth weight), family (socioeconomic disadvantage, family history of language difficulties), and maternal factors (education, vocabulary, and age). Language (standardized assessment of receptive and expressive skills) and academic (national assessment) outcomes at 11 years were predicted by using a series of multivariable regression models. Results: Early life factors explained 11% to 12% of variance in language scores at 11 years. The variance explained increased to 47% to 64% when language scores from 2 to 7 years were included. The largest increase in variance explained was with 4-year language scores. The same early life factors explained 13% to 14% of academic scores at 11 years, with increases to 43% to 54% when language scores from 2 to 11 years were included. Early life factors adequately discriminated between children with typical and low language scores but were much better discriminators of children with typical and low academic scores. When earlier language scores were added to models then the area under the curve increased to 0.9 and above. Conclusions: Children's language outcomes at 11 years are accurately predicted by their 4-year language ability and their academic outcomes at 11 years are predicted by early family and home environment factors. Children with low language abilities at 11 years consistently performed more poorly on national assessments of literacy and numeracy.