While many insurance comparison have made significant improvements and are consistently providing clear, fair and not misleading information, some are still not doing enough, according to City watchdog the Financial Services Authority.

Comparison websites should do more to obtain better information from insurers about the level of excesses that apply to insurance policies, and should be clearer about the assumptions they make about consumers' needs and circumstances that some websites use to obtain quotes, the FSA has found.

The findings came from visits to a number of firms, representing over 50% of the market in terms of sales volume.

The FSA found firms were generally showing the level of excess on each quote, but in most cases firms were unable to show the split between compulsory and voluntary excesses - often because the relevant information had not been supplied by the provider.

Where this information is not available from the provider, this should be made clear to the customer, the FSA said.

They said aggregators and insurers should work together in making this information available.

Insurance aggregators make assumptions to generate quotes quickly but these are not always set out clearly, the FSA said.

Examples of such assumptions are that the applicant is the main driver of the car and not a professional driver; that the applicant has been driving regularly since the date that his licence was issued, or that the vehicle is not a van or commercial vehicle and is not used for hire, trade or delivery.