There is an emergent need to examine teachers' acceptance of distance education through LMS during emergencies to leverage online teaching and learning to enhance teachers' future readiness for digital transformation in education. This study explores Saudi teachers' perceptions of Madrasati (national e-learning system). It investigates its ease of use, usefulness, behavioural intention to use the system, and its actual use in association with external factors from teachers' perspective to identify the platform's most supportive elements during remote online teaching due to the COVID-19 pandemic. The findings from 197 participants show that teachers positively perceived Madrasati regarding the system's external variables, including content quality, teaching support, visual design, system navigation features, ease of access, system interactivity, and instructional assessment tools, and they positively perceived the system's learnability.