Quilter's protection business paid 99.78 per cent of life and 96.2 per cent of critical illness claims in 2018, taking its total payouts in the past two years to almost £150m.
In 2018, Old Mutual Wealth paid out £37.3m in life insurance claims – with an average size of £82,931.
Meanwhile the company also paid out £19.3m in critical illness claims, with an average size of £126,889.
For the third year in a row Quilter said it had increased its percentage of successful critical illness claims and now pays out nearly 6 per cent more than in 2016.
The company said that during 2018, some 84.9 per cent of critical illness claims were made for just three conditions. These were cancer (66.45 per cent) stroke (7.24 per cent) and heart attack (11.18 per cent).
Quilter's protection arm is still branded as Old Mutual Wealth but will shortly change its name as part of the business's demerger from its South African parent company last year.
Paul Roberts, head of protection at Old Mutual Wealth, said: "When people come to us at the claim stage they are often at a vulnerable moment in their life as they might be grieving for a loved one or scared because of a worrying diagnosis.
"For this reason, it is of paramount importance that we continue to give our customers a dedicated and empathetic service, which helps guide them through a difficult time."
In July 2018, the company overhauled its critical illness plan, with the inclusion of a total of 49 conditions where there will be 100 per cent payment, as well as 28 additional payment conditions at £25,000 or 25 per cent of the sum.
At the time, Alan Lakey, founder of CI Expert, said Old Mutual Wealth had gradually "slid down the table" in terms of what its plan covered in relation to its competitors, because it had not updated its policy significantly over the course of five years.
But Mr Lakey hailed Old Mutual Wealth for becoming "another major insurer to refresh its CI plan" after making a series of upgrades.
