Academic writing is one of the most crucial skills for university students across the globe; however, the conventions of writing vary across different cultures. This research study used a multidimensional approach to analyze Saudi students' writings compared to British students. A specialized corpus of Saudi academic English writing (CSAEW) was developed to explore interdisciplinary lexico-grammatical patterns. The data was collected from the undergraduate students enrolled in the universities from three regions across the Kingdom. The CSAEW was compared with the British Academic Writing English corpus. Biber's multidimensional model was used to examine linguistic features along dimensions such as involvement, information, argumentation, narration, and abstraction. The study provides evidence about how Saudi students prefer particular lexical and grammatical patterns over others and how Saudi academic writing is distinguished compared to British academic English. The study results indicate that CSAEW is more explicit and non-narrative than BCAW. There are marked differences on dimensions 1, 4, and 5. The mean scores of CSAEW and BCAW fall on the opposite side of the continuum. The findings document the patterns of linguistic variation in Saudi students' academic writing compared to that of British students. Based on the pattern of variation, the study provides some recommendations for pedagogical practices to improve Saudi students’ writing skills.