Zurich Group's affinity division, Home & Overseas (H&O), has snatched a multi-million pound affinity deal with building society, Bradford & Bingley, from under the noses of rival insurer, Axa.
H&O beat off seven rival firms to land the deal - including incumbent insurer Axa.
The building society has 80,000 policyholders and a potential market of 2.7m account holders.
H&O sales and marketing director Jon Seal said: "This cements our existing relationship with the building society and provides us with one of the largest travel books in the financial services sector of the market."
The two-year contract became effective on May 2 when H&O began underwriting new policies and renewals.
H&O will start by underwriting the same annual and multi-trip travel policies as Axa wrote. Later this year H&O plans to launch at least one new travel product.
Zurich has provided Bradford & Bingley customers with household cover for 53 years continuously.
The building society launched its travel cover three years ago which was originally underwritten by Axa.
Paul Shearman, head of Zurich Group's strategic partnerships, said: "We are absolutely delighted to have won this deal, which we believe to be the biggest in the UK along with Lloyd's TSB."
B&B's general insurance marketing manager Ian Campbell believes the new deal will help Bradford & Bingley increase its presence in the travel market.
Other bidders for the contract included GE and CGU.