The Old Mutual Wealth group now totals 3,700 advisers with the addition of 300 from Caerus.
The deal was agreed by the Caerus board in February and has now received shareholder and regulatory approval.
Caerus network will become a wholly-owned subsidiary of Intrinsic, with Caerus advisers adopting the Intrinsic advice process over a phased transition, which will be managed on a firm by firm basis.
Intrinsic already has Positive Solutions and Sesame Bankhall Group advisers under its brand, and has also launched Old Mutual Wealth Private Clients Advisers.
Caerus chief executive Keith Carby (pictured) will leave the business after completion while managing director, Andy Ferns, will stay on to support the transition to Intrinsic.
Carby thanked the staff and advisers for their hard work and said the transaction highlighted the quality and value of their work.
Intrinsic CEO Andy Thompson added: “I’m delighted to welcome the staff, advisers and clients of Caerus into the Intrinsic network.
“Caerus has grown to become one of the most highly-regarded networks in the industry, and we now have a fantastic opportunity to continue our growth together.
“I’d also like to thank Keith Carby for the remarkable contribution he has made to Caerus and for giving Intrinsic the opportunity to continue that work.”