The £550m deal, which was announced last November, will see Aberdeen overtake Schroders as Europe's biggest asset manager.
Aberdeen chief executive Martin Gilbert said the integration process will begin soon after completion and a trading statement is expected on 1 April.
Largest listed group
The merged group will be responsible for combined assets under management of approximately £330m, positioning Aberdeen as Europe's biggest listed fund group.
Gilbert said the deal broadens the investment capabilities of both businesses, with a stronger and more diverse range of investment management skills as well as significant scale across asset classes and geographies.
He tipped this week's Budget announcement as an opportunity for the group, with the more flexible rules around pension drawdown.
Long-term benefit
In a statement to the stock market, Gilbert added: "We will continue to work closely with SWIP and Lloyds Banking Group to ensure a smooth completion process. The way we have already worked together to develop a structured integration plan is very encouraging and means that the migration process will begin very shortly after completion.
"This co-operation confirms my belief that the combination of the two businesses and our strategic relationship with Lloyds will be of great long-term benefit to our shareholders and clients, whom I would like to thank for their continued support throughout this process. Everyone at Aberdeen is looking forward to working with our new colleagues from SWIP."
