Aviva is closing offices in Salisbury, Stretford and Salford, as the former Friends Life base in Dorking will become a hub for its corporate pensions business.
The closures, which could lead to job losses believed to be in excess of 700, are part of a restructure that aims to cut £225m a year from expenditure through the £5.6bn takeover.
Any job losses resulting from the closure will form part of the 1,500 potential reduction in headcount already announced in January 2015.
Aviva’s core locations in the UK will in future be Bristol, Norwich, Perth, Sheffield and York, supported by specialist and trading sites in Belfast, Birmingham, Bishopbriggs, Cambridge, Chelmsford, Croydon, Dorking, Exeter, Isle of Man, Eastleigh, Glasgow, Leeds, Leicester, Liverpool, Manchester, Newcastle, Southend and Worthing. Group headquarters will remain in London.
The insurer says it remains firmly committed to the UK market.
An Aviva spokesperson says: “There will be a reduced presence in Dorking, but it will remain a specialist site for our corporate pensions business. We will also have a reduced presence in Exeter and Manchester city centre.
“We appreciate this is disappointing and difficult news for some of our employees and we are helping our people through this process, providing a range of support and advice, and consulting with employee representative bodies about these changes.
“The changes will happen between now and the end of 2016 and we will look to minimise the impact by offering redeployment opportunities where possible.
“The UK is an attractive insurance market and is critical to Aviva’s success. Today’s announcement is part of our long-term strategy to become more efficient and strengthen our position as the leader in our home market.”