The LV= board concluded that member interests were best served by focusing on the firm’s insurance and life business.
The possibility of the outsourcing deal was announced by LV= last month.
Mike Rogers, LV= group chief executive, said: “The outsourcing of the management of LV=’s assets represents another step in our plan to ensure our structure continues to provide best value for our members.”
LV= currently has £8.4bn assets under management. It says there are likely to be some redundancies from the LV= asset management team with the deal although some staff will be transferred to Threadneedle Investments.
The main funds will remain in their current structure when they transfer and will stay segregated.
Crispin Henderson, chief executive of Threadneedle Investments, said: “LV=’s decision to partner with Threadneedle reflects the strength of our investment team, our process and our sustained long-term track record of excellent performance across asset classes.
“We are committed to ensuring a smooth transfer for investors over the coming weeks and months.”
Threadneedle Investments is the fourth-largest retail fund manager in the UK with over £68bn in assets.
The transfer is expected to take place on 31 October.