Embark Group and Mazars have announced a joint venture, combining their employee benefits consultancy arms into a single company called Vested.
The business, which will be owned 51 per cent by Embark and 49 per cent by Mazars, will target small and medium-sized businesses with between 100 and 750 employees.
At the same time, in a separate deal, Embark will sell its financial planning business, RCL Consultancy, to Mazars for an undisclosed sum.
Phil Smith, chief executive of Embark, said Vested will "look beyond" traditional flexible benefits and auto-enrolment.
He said: "Access to flexible savings delivered in a compliant way is where the story of the next five to 10 years is going to be.
"We are in the market selling services to the IFA and advisory market and Mazars are in that market buying services from us and in that time we went from a product-based conversation to a strategic one.
"We have a common view about there the market in the UK is heading."
Vested's services will cover workplace savings, employee engagement, flexible benefits and financial wellness.
Ian Pickford, head of Mazars Financial Planning, said: "Over the last three or four years everyone has been completely focused on auto-enrolment and it has been in a pretty plain, vanilla way."
He said that once companies had complied with auto-enrolment, they would start looking beyond its basic requirements and consider what they should do for their employees' financial wellbeing, beyond just pensions.
Mr Pickford said: "Financial advice will be required in a workplace setting and increasingly employers will be willing to pay for that."
He added that Mazars Financial Planning would remain independent, and the joint venture with Embark would not affect the recommendations Mazars' planners give.
The sale of RCL Consultancy means a portfolio of high net-worth clients with assets of around £300m will transfer between the two businesses and will mean Embark will have no presence in the financial advice market at all.
Mr Smith said the two companies did not necessarily have ambitions for Vested to be a huge player in the employee benefits sector, saying he wanted the company to be "scalable" and to be known for quality rather than size.
He said: "We are not trying to be Mercer. If that means we are managing 200 clients or 20,000, I don't think that is front of our minds."
Both transactions are subject to regulatory approval but it is hoped the deal will be completed by the end of the year.