Capita Group has announced a 17% increase in turnover boosted by its £10m two-year deal to run Hill House Hammond run-off business.
The company said it had won significant business through its London market operations, and legal and medical helplines.
A company statement said: "We are continuing the refocusing of our volume loss adjusting services into higher value added propositions utilising our newly-implemented SAP technology."
However the growth could be threatened by a potential sale of Abbey to Spanish bank Santander Central Hispano.
Market analysts suggest a sale of Abbey could lead to a review of all the bank's existing contracts. This would include the £30m per year deal with Capita to run claims and administration on its insurance book, which includes home and motor policies.
A spokeswoman for Capita said: "We will just have to wait on see on that. It is very early days and no sale has been agreed."