This study examines the effect of enhanced input of lexical chunks on the performance of Arabic-speaking English learners' writings. Lexical chunks, containing their forms, meanings, and functions, stored and recovered as a single component in brains, may alleviate language processing problems and increase language proficiency. The research examines if enhancing exposure to lexical chunks might advance foreign language learners' writing in Saudi Arabia. The study attempts to find an answer to the following question: What is the potential impact of rich input of lexical chunks on Arabic-speaking learners of English e-mail writing competence? A total of 34 female university students were divided into two groups and given a pre-test and post-test in which they wrote and composed e-mails in English. The experimental group was then exposed to a treatment (i.e., extensive exposure to lexical chunks available via an e-mail phrase bank). After eight weeks of treatment, the experimental group outperformed the control group on the posttreatment test. The results demonstrate that learners with more lexical chunks are more likely to perform better and vice versa. The results indicate that the experimental group had a favorable attitude about lexical chunks through the e-mail phrase bank. The results suggest that abundant input of lexical chunks aids in improving learners' writing performance. The findings also suggest that increased input of lexical chunks may lessen the potential negative transfer of the mother language, therefore refining writing in terms of collocations, grammatical structures, and discourse coherence.