Based on the issue price, the market capitalisation of the Group on admission will be c.£125m.
Chief executive Euan Fraser, said: “Today’s announcement marks a very exciting new phase of Alpha’s journey as a leading consultancy to the asset and wealth management industry.
“We are absolutely delighted at the strong response to the placing and the recognition from investors of the significant opportunities we have for continued global growth.”
The company has offices in the UK, US, France, the Netherlands, Luxembourg and Switzerland.
Works with advisers
Alpha work with wealth managers, covering private banking, wealth solutions, discretionary fund management and family office services.
It also works with advisers, platforms, clearing houses, exchanges, utilities and brokers around the world.
£89m will pay exiting private equity owners Dunedin with the rest going on debts and listing expenses.
Admission and commencement of dealings in Ordinary Shares under the ticker AFM are expected to take place at 8.00am on 11 October 2017.
AIM is a market designed primarily for equity securities of small and medium sized growth companies that may have less diversified business models or may not yet have the track record to qualify for the main market.