The total liabilities of the UK non-life run-off market are estimated at £41.1bn, according to a KPMG survey.
This represented a 6.2% increase compared to the previous year.
The report, which was commissioned by the Association of Run-Off Companies (ARC), said the liabilities of the non-life run-off market in the UK represented approximately 25% of the non-life run-off market as a whole.
The net assets, or shareholders' funds, of UK non-life business in run-off totals £3.8bn.
The report said: “There is no reason to assume that the increase in the size of the run-off market will reverse, although the rate of that increase is difficult to predict.
“What is clear is that rather than being a diminishing issue for the insurance industry, it is one that will continue to require active management in order to ensure that value is preserved and trapped capital is released.”