Aviva paid 92.5% of critical illness (CI) claims during the first six months of the year.
The provider paid 755 CI customers an average of £81,000 each totaling £62m between January and June 2011, a 21% increase on the same period last year.
The approval rate was down slightly from its 2010 end of year figure of 94.7%, with just 1.5% declined for non-disclosure and the remainder for not meeting the condition.
The average age of female claimants was 44 years and two months and 45 years and three months for males.
Cancer remains the most common cause of critical illness claims at 65.9%, followed by heart attack (11.3%) and stroke (7.9%).
Aviva also paid £150m to life insurance claimants with 99.7% of claims resulting from death approved.
Robert Morrison, chief underwriter for Aviva, said: "We believe it is crucial to pay every claim we can.
"While unfortunately across the industry there are a small number of claims insurers are unable to pay - for example when they do not meet policy criteria or if there is a clear case of deliberate non-disclosure - these latest figures should help to reassure customers that we are there to help them when it matters most.
"We would like to see critical illness claims figures rise even higher across the industry and we are constantly reviewing how we work with our customers and advisers to assist them from the point of purchase," he added.
