Sam Mascareno

Enterprise Markets Leader, Partner

About Sam

Sam Mascareno is a partner and enterprise markets leader for RSM US LLP. He is a member of the firm's executive leadership team, markets team and operations team. In these roles, Sam oversees the execution of the firm’s growth and culture objectives across all markets in the United States and Canada. He is also the executive sponsor for key firmwide initiatives involving RSM’s client and talent experience. 


Based in RSM’s San Diego office, Sam joined RSM in 2001 and has extensive experience providing tax services, including tax compliance, consulting and structuring. Prior to RSM, Sam specialized in tax at a Big Four firm, focused on cross-border/international tax planning and compliance services. He has extensive experience with large-scale projects and tax consulting for international clients with foreign ownership or operations within various industries, including life sciences, technology and manufacturing.

Sam is invested in the talent experience at RSM and serves as a guide and mentor for younger professionals in the firm. He has worked with the RSM US Foundation to sponsor junior college scholarships for ethnic minorities to pursue a four-year degree and a career in public accounting. Sam is also the co-founder of ¡HOLA!, the firm’s employee network group (ENG) for Hispanic and Latino professionals and part of the firm’s Inclusion Council overseeing all of RSM’s ENGs.

Professional affiliations and designations

  • Certified professional accountant 
  • American Institute of Certified Public Accountants 
  • San Diego State University School of Accountancy, board member


  • Bachelor of Science, accounting (honors), San Diego State University – California State University 
  • Master of Science, tax (honors), San Diego State University – California State University