Marilou Tan joined the Treasurer-Tax Collector in November 2015. She served as the Administration Manager and Treasury Manager for the agency before becoming the Assistant Treasurer-Tax Collector in 2022. Prior to her career in public service, Marilou worked in the private sector, where she has 20 years of combined experience in SEC and financial reporting, SOX compliance, auditing, finance, and accounting. She has been a Certified Public Accountant since 2000. Marilou has earned the Certified Public Funds Investment Manager (CPFIM), the Advanced Certified Public Funds Investment Manager (ACPFIM), and the Certified Public Finance Administrator certifications from the Association of Public Treasurers of the United States & Canada (APT US&C). She received a Bachelor of Science in Accounting and Finance, and a Master of Public Administration from California State University, Northridge.

Marilou is honored to serve as the Assistant Treasurer-Tax Collector. She is committed to providing superior and cost-effective customer service to the residents, agencies, and employees of Ventura County.