Aviva paid 93.5% of income protection claims in 2012, the insurer's claims statistics have shown.
The data also shows the insurer paid 99.3% of life insurance claims and 92.5% of critical illness (CI) claims.
Non-disclosure was cited as the reason for decline for 0.7% of life insurance claims, 0.4% of individual income protection (IP) claims and 1.7% of CI claims.
The figures include £324m - up £4m from 2011 - paid to the families of life insurance customers who have died or been diagnosed with a terminal illness, and more than £131m paid to customers with CI cover.
Payments to IP customers was up £1.3m since 2011, totalling £15m.
The average length of claim for an IP policy was nine years and five months while the most common causes for claim were psychiatric conditions (30%); orthopaedic conditions (21%); neurological conditions (18%); rheumatological conditions (10%); and cancer (8%).
The average age for claimants was; 52 years for women and 55 years for men claiming IP; and 44 years for women and 46 years for men claiming CI.
Cancer remains the most common cause of CI claims at 66%, followed by heart attack at 12%, stroke at 7%, 5% claiming for multiple sclerosis and 3% for benign brain tumour.
These top five conditions accounted for 92% of Aviva's CI claims overall in the last five years.
Robert Morrison, chief underwriter for Aviva, said: "Our latest figures are great news. Protection policies are the types of products no-one ever wants to claim against, but the financial comfort they offer at a difficult time cannot be underestimated.
"Almost 14,000 of our customers and their families benefited from payments last year, so people can be reassured that we are absolutely committed to paying claims wherever possible.
"We will continue to work with our customers to ensure if they need to make a claim, their journey is as quick and straightforward as possible."
