Which? has renewed calls for the insurance industry to bar the use of premium rate phone lines for customers.
Research by the firm found that 79% of home insurers use an 084 or 087 number for customer lines, meaning customers could pay up to 41p a minute to speak to their insurer or broker.
Which? said that firms involved include Ageas, Aviva, Axa, Churchill, Direct Line, Esure, Hiscox, RSA and Virgin.
Under incoming consumer rules, customer service and complaints lines will be barred from using 0845 numbers from June, but the rules will not cover insurance companies, while Prime Minister David Cameron recently forced the Environment Agency to change its flood helpline from an 0845 to an 0345 number.
Which? executive director, Richard Lloyd said: "We're pleased the Prime Minister has this issue high on his agenda and the insurance companies must to do everything they can to make things easier for flood victims who shouldn't have to pay a premium to make a claim, especially when many will be calling from a mobile.
"The Government must also make sure other public bodies play fair and drop high rate numbers as soon as possible so that people are not left out of pocket when calling essential services."
