Phoenix Life has committed to leaving terms and conditions on Standard Life policies unchanged following the takeover of the assets later this year.
The consolidator is to acquire the life company's book of insurance contracts, including annuities and workplace pensions, as part of a £3bn deal announced to the stock exchange today (23 February).
Phoenix told FTAdviser it "will not be changing their terms and conditions in any way", including the fees and charges currently in place for the products.
Meanwhile, Standard Life has written to advisers confirming there would be no changes to its strategy for on-platform clients, who it will retain.
But Dave Penny, managing director of Invest Southwest, said there could be trouble ahead, including potential client grabs.
He said: "In my experience I have very rarely investigated a policy now under the control of Phoenix without reaching the conclusion that charging structure, service levels and performance of the product are poor or quite simply out of date, whether it contains an insurance element or not.
"So this is almost certainly good news for the corporates in their cash generation and bad news for clients. I imagine it will result in more amendments being necessary and more work for us."
But Alistair Cunningham, financial planner at Wingate Financial Planning, who also has Standard Life clients and has experienced a client transfer to Phoenix before, expected business as usual.
He said: "Because it is mainly historic business it does not mean an awful lot for new clients and for us as a firm.
"We mainly have platform clients and they are keeping their platform."
Mr Cunningham said when Axa clients were moved to Phoenix in May 2016 he hadn't faced issues and the policies' fees had remained the same.
Kusal Ariyawansa, a chartered financial planner at Manchester-based Appleton Gerrard, was also unperturbed by the news.
He said: "I have got legacy clients with both and Standard Life has been in touch with me today saying it is business as usual. I don't see there being any change from my end as it doesn't affect my core clients really."
The deal will see £166bn of insurance assets moved to Phoenix, while Standard Life Aberdeen will retain the core of its retail channel and position itself as a 'capital light' investment business.
The financial services giant already owns adviser platforms Wrap, Elevate and Parmenion and financial advice business 1825.
Since the acquisition of Elevate in October 2016 its assets under administration (AUA) have grown 16 per cent to £12.9bn, bringing the combined AUA on the platforms to £54bn, an increase of 22 per cent over 2016, the firm's results showed today (23 February).
Standard Life Aberdeen also agreed a long-term strategic partnership with Phoenix after taking a 19.99 per cent stake in the firm.
In particular, it is eyeing further investment management mandates through Phoenix, alongside the £158bn of assets it already manages.