The firm said the practice brings in £65 for every car and £21 for every home.
Other major insurers such as Aviva do not break out how much they are pocketing in their annual accounts.
Aviva boss Mark Wilson told the Mail this was because the amount is very small.
Finance expert Justin Modray, of advice firm Candid Money, said consumers who sign up for insurance online are sitting ducks.
Insurers can lure these customers in with a rock-bottom basic premium, without showing whether their add-on costs are competitive or not.
Other major insurers such as Aviva do not break out how much they are pocketing in their annual accounts.
Aviva boss Mark Wilson told the Mail this was because the amount is very small.
Finance expert Justin Modray, of advice firm Candid Money, said consumers who sign up for insurance online are sitting ducks.
Insurers can lure these customers in with a rock-bottom basic premium, without showing whether their add-on costs are competitive or not.
Labour MP John Mann accused companies of treating customers like cash cows
Mr Modray said he was charged £40 for extra legal cover by one insurer but found exactly the same level of service from an independent provider for £20. He said: ‘The insurance industry has gone the way of the budget airline industry with really basic cover where you need to add on a lot of extras. If people aren’t careful they might go for the cheapest deal and end up paying a lot of unexpected fees.’
Mr Modray said he was charged £40 for extra legal cover by one insurer but found exactly the same level of service from an independent provider for £20. He said: ‘The insurance industry has gone the way of the budget airline industry with really basic cover where you need to add on a lot of extras. If people aren’t careful they might go for the cheapest deal and end up paying a lot of unexpected fees.’
The Association of British Insurers said firms have to disclose fees and charges, and added: ‘Consumers should shop around.’ Hastings said: ‘Our ancillary fees and charges are in line with others in the market and our premiums are some of the most competitive.’
Esure said: ‘Instalment income has risen simply as a result of the company selling more policies and the higher average premiums being seen across the industry.
‘We are very clear on the difference customers will see in the prices if they pay by instalments.’
Direct Line said it does not charge fees to amend policies, and the charge for paying by monthly instalments is communicated clearly to customers when they receive a quote.
Admiral declined to comment.
