Academic vocabulary knowledge predicts students’ academic achievement across educational levels. English academic vocabulary knowledge is especially valuable because English is used in academia worldwide. Therefore, examining the factors that can predict English academic vocabulary knowledge can inform pedagogy, thus indirectly boosting students’ chances of academic success around the world. This study examines the extent to which cognateness, word frequency and length predict the ability of English as a Foreign Language (EFL) learners who have Spanish as their first language (L1) to recognise written English academic words. 38 Spanish L1 university students’ recognition knowledge of English cognates was measured via a Yes/No test containing words sampled from the most frequent 1,000 lemmas of the Academic Vocabulary List (Gardner and Davies 2014). 34 participants’ data were retained in the final analysis, a multiple regression with item facility (IF) as the outcome variable and word frequency, cognateness and word length as predictors. Most of the IF variance is explained by word frequency, followed by cognateness and finally a frequency by cognateness interaction whereby word frequency is more predictive of IF for non-cognates than cognates. These findings indicate that academic cognate-word awareness raising activities can be worthwhile. Implications for research and pedagogy are discussed.