Informal entrepreneurship (IE) has received increased recognition because of its theoretical distinctiveness and practical relevance. However, the burgeoning literature on IE is difficult to navigate, due to its rapid growth across different disciplines. Through an integrative review, we introduce a novel typology of informal entrepreneurs that captures their heterogeneity across various contexts. We point out a dynamic perspective of IE, consisting of three pathways—the reactive formalizing, the proactive formalizing, and the informalizing pathways—along which informal entrepreneurs move, acquiring or foregoing regulative legitimacy. Our review extends the theory on IE, outlines promising research avenues, and suggests relevant practical implications.