Entrepreneurial ecosystems in West Africa are characterised by distinct institutional frameworks that shape venture development. Togo presents a critical case due to its specific policy reforms and economic positioning within the region, yet a longitudinal, comparative analysis of its institutional challenges is lacking. This study aims to compare the evolving institutional challenges faced by Togolese entrepreneurs across different venture stages and sectors, and to analyse their consequent growth trajectories relative to regional benchmarks. A mixed-methods comparative design was employed, integrating longitudinal survey data from a stratified sample of registered enterprises with in-depth interviews of founders and policymakers. Quantitative growth metrics were benchmarked against a constructed regional dataset. A predominant theme identified was the disproportionate constraining effect of informal, ad-hoc regulatory enforcement compared to formal laws, cited by over 60% of high-growth firms as a key impediment. Ventures in the agri-processing sector demonstrated more volatile growth patterns than those in digital services. Institutional challenges in Togo are not static but evolve with venture maturity, with informal practices becoming more significant constraints than codified regulations as firms scale, thereby creating a non-linear growth trajectory. Policymakers should prioritise the standardisation and transparency of regulatory enforcement over legislative change. Support programmes require segmentation based on venture stage and sector to address distinct institutional hurdles. Entrepreneurial ecosystem, institutional voids, growth trajectories, comparative analysis, business environment, West Africa This paper provides a novel, longitudinal dataset tracking Togolese firm-level growth alongside perceived institutional challenges, offering a granular, stage-sensitive analysis previously absent for the region.