Parmenion is to allow advisers to access external discretionary fund managers and model portfolios on its platform, but says it is not intending to mimic wrap platforms.
Martin Jennings, chief executive of Parmenion, said advisers regularly gave him feedback about how much they liked the company's offering, but complained about a lack of "breadth of product".
Third party DFMs cannot currently put their propositions on the Parmenion platform, but some advice firms - such as Ascot Lloyd - do already have their DFM proposition on the platform.
Jennings said he was keen to open up the Parmenion platform further.
He said: "We are going to allow multiple model portfolios and DFMs on the platform but we are not here to become a wrap platform. We can't out-platform the platforms.
"This isn’t distribution of product. This is about meeting a core need from the adviser. That’s a big change for us to open our proposition up.
Jennings added Parmenion would only make a DFM proposition available on its platform if an adviser asked for it, adding that DFM providers wouldn't be able to ask the company to become available themselves.
"We are going to allow people to run advisory portfolios as well as discretionary portfolios. I think we can help people solve the problem of running multiple model portfolios, improving the adviser-client relationship and helping simplify that process.
"We want to be seen as the provider of choice by those firms that want to implement a centralised investment proposition."
He said Parmenion, which has assets of £9bn, was aiming to double its assets under management over the next five to 10 years.
Parmenion is backed by private equity firm Preservation Capital Partners and Martin Gilbert's investment vehicle AssetCo.
Jennings said: "We have got a five-year plan, we are well invested and well funded and we are going to spend significant amounts of money to expand the proposition."
Parmenion is also interested in acquisitions either to grow the platform's assets or capabilities.
"We are not going to go out there and buy a platform to create synergies, but we may buy capabilities. That might include reporting, data management or artificial intelligence. Anything that improves the adviser/client relationship."
He said the ESG space was another area where Parmenion might be interested in doing a deal.