Town & Country will continue to offer existing services to fleets, such as accident management, and Theodore Agnew will remain as its chief executive. He has also been made part of the WNS management committee.
The acquisition expands the specialist outsourcing portfolio owned by WNS, while providing Town & Country the finance to expand, including a new venture in North America.
Town & Country has an accident management fleet of 250,000 vehicles and handles 120,000 motor claims each year.
WNS, which has British Airways as a key shareholder, includes finance, accounting, customer relationship management, HR and benefits administration in its portfolio of outsourcing services.
Agnew said: 'This acquisition adds significantly to our resources and gives us many times the capacity and investment to handle larger contracts from both our existing and prospective clients.'
Steve Dunning, chief executive officer of WNS added: 'The acquisition brings rich insurance sector experience and a best-in-class operating team to strengthen our foray into the business process outsourcing market.'