Chris Hull, head of operations at Aegon-owned national IFA Positive Solutions, has left the company after nine years.
A spokesperson for Aegon said Hull would leave the firm in November to pursue other opportunities.
"Chris has been a hard-working and popular member of staff at Positive Solutions for over nine years and we wish him well with his new challenge," a statement read.
A replacement is yet to be found.
Hull is the sixth senior figure to leave Positive Solutions, which posted a loss of £630,000 last week, in as many months.
Recruitment director Martin Brown left earlier this week, while last month the firm was hit with a double departure, when it was announced head of propositions Andrew Waldron and business development director Jonathan Morley had also handed in their notices.
Risk and compliance director James McCourt departed in May to join Royal London.
CEO Jim Reeve quit in February to pursue "alternative opportunities" in financial services. He has since set up as a self-employed consultant.
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