Previous research has furnished evidence that alliterative expressions (e.g. "a slippery slope") are comparatively memorable for second language learners, at least when these expressions are attended to as decontextualized items (Lindstromberg and Boers, 2008a; Boers et al., 2012). The present study investigates whether alliteration renders lexical phrases comparatively memorable also when these phrases are encountered in texts read primarily with a focus on content. Fifty-four EFL students read a text adapted so as to include five instances of 12 idiomatic expressions. The results of surprise post-tests suggest that the alliterative phrases among these target expressions left significantly stronger memory traces than the non-alliterative ones, especially regarding the form or composition of the phrases.