Early-Start Effects in EFL Settings: A Critical Review of Long-Term Evidence Beyond the Primary School Years

This paper critically reviews long-term evidence on early English instruction in foreign language settings beyond the primary school years. It examines how early-start effects change across the transition to lower-secondary education, later school years, and college-level contexts, and which conditions are associated with their persistence, weakening, or re-emergence. Using a timeline approach, the review synthesizes school-based and post-school evidence across these stages. The findings indicate that early-start advantages are unstable, context-dependent, and often domain-specific rather than automatic or cumulative. Although cumulative exposure matters, the evidence does not support a consistent exposure threshold at which durable advantages emerge. Cross-study comparisons are also constrained by differences in assessment constructs and their alignment with program aims. Lowering the starting age alone is therefore unlikely to produce lasting benefits unless early instruction is supported by sustained, high-quality input, coherent curricular progression, careful transition planning, and meaningful opportunities to use English across educational stages.