Last financial year there were 33,172 general insurance complaints to the Financial Ombudsman Service compared to 19,102 in 2009.
The Consumer Panel said this increase of 14,070 complaints could just be the tip of the iceberg, as not all dissatisfied customers escalate their complaint to the Ombudsman.
Sue Lewis, chair of the consumer panel, said: "General insurance is vital to help people manage the risks of modern life.
“The average UK household spends £822 a year on general insurance products.That is a lot of money.
“Comparison websites make shopping around for a good insurance deal look easy, but people may find if they claim that their cover isn't what they expected, or they face a large excess.”
Lewis said the Consumer Panel’s research has highlighted several areas where firms could do better.
She said: “They [insurers] must make it clear to customers up front exactly what they are paying for, and treat claims fairly.
“The FCA has recognised the importance of firms' culture to good consumer outcomes, and we strongly support its focus on this area.
“We hope our research will help inform the FCA's work and lead to better treatment for insurance customers."
