Puerto Rican SMEs (Small-to-Medium Enterprises) represented 80.8% of the total enterprises in 2020, contributing to 38.6% of formal jobs (Informe Economico al Gobernador 2020, 2020). One main management goal is defining how the business will leverage its regular operation, also known as determining its Capital Structure (CS). It has been identified that one of the significant SME causes of failure is its financial leverage decisions and having to find a feasible CS composition that fits in with its current chart of capabilities and business structure. Thus, this investigation generalizes the CS variables based on a qualitative e-Delphi approach, concluding which literature variables are essential to SMEs CS in Puerto Rico. The expected investigation outcome is to obtain a list of focus variables that enable academically oriented SME investigators and financial decision-makers to optimize their resources and efforts.