Bluefin Corporate Consulting is merging with Capita Hartshead after being sold by its parent company AXA to Capita for £50m.
The firm will merge with Capita's pension and employee benefits business Capita Hartshead after AXA said the firm was "no longer aligned" to its long term strategy and "core lines" of business.
Bluefin chief executive Nick Burns will become chief executive of the combined business.
The deal does not include Bluefin Personal Consulting, which provides wealth management services, or Bluefin Insurance Group, and AXA will retain the Bluefin trading name.
Burns said: "Clients want to work with talented people who really understand and care about them.
"I believe that Capita Hartshead's strength in pensions administration, actuarial and consulting, together with Bluefin's award-winning employee benefits expertise and market-leading online technology, will combine to deliver a wide range of client services.
"With the full backing of a FTSE 100 company, this new business will be able to provide genuinely innovative solutions to the rapidly evolving and increasingly dynamic employee benefits market."
Clarke replacing Balkham
'Deep-dive analysis of client behaviour'
Ways to mitigate April’s increases
The best equity income funds examined