Universities worldwide are investing in digital technologies to improve teaching and learning. However, establishing smart digital learning environments requires more than providing technological infrastructure; it depends on how universities develop, connect, and sustain digital systems. This study examined the extent to which Tanzania's Higher Education for Economic Transformation (HEET) initiative has contributed to the development of smart digital learning environments in public universities. A convergent mixed-methods design was employed, involving five public universities that implemented the initiative. Quantitative data were collected from 271 academic staff, while qualitative data were obtained through interviews with ICT and physical infrastructure leaders and supported by institutional observations. Descriptive statistics, one-way ANOVA, and thematic analysis were used to analyse the data. The findings revealed moderate progress towards smart digital learning environments, driven by improved ICT infrastructure, internet connectivity, smart classrooms, and digital learning platforms. The progress differed significantly across universities, F(4, 264) = 7.51, p < .001, indicating that institutions transformed at different levels. The findings further indicated that these differences were influenced by implementation progress, existing digital capacity, and institutional coordination. The study concludes that building smart universities requires not only investment in technology but also strong institutional systems that support sustainable digital transformation.