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Key findings

• Since 2012, the cost of making a material change to a policy part-way through the year, such as changing the name, address or occupation listed, or adding or removing a named driver, has risen by 38%. Although nearly a fifth of policies allow drivers to amend their own policy online, a charge is made if the change is facilitated through a call center — despite the fact that policyholders are contractually obligated to advise their insurer of changes in their circumstances or to the insured vehicle, and failure to do so could invalidate their cover.
• Cancellation charges have increased by 49% since 2012. Motorists can cancel their insurance at any time during the term of the policy if they no longer need it, and insurers are legally required to give a 14-day "cooling off period" — meaning that policyholders who want to end a policy within the first two weeks are eligible for a refund. An administration fee may still be applicable, however, and motorists will be charged for the number of days for which they were covered.
• While still a relatively rare fee, the number of policies under which policy set-up fees are payable has shot up from 12% in 2012 to 38% of policies in 2019.
• Duplicate policy documents have fallen by 25% since 2012. This is likely linked to the rise of digital documents in recent years.

"The car insurance market is highly competitive, so rather than incorporating the costs of certain admin tasks into the basic premium, some insurers make other charges. This helps keep premiums down by ensuring that only the policyholders who change or cancel their policy, for example, pay for the additional work required to administer their policy," Lee Griffin, founder and CEO of GoCompare, said in a statement.

"Insurers should be upfront about any admin fees they charge. These should be clearly set out in their terms and conditions, so drivers are aware of the full costs before signing up to a policy. Fees should also be proportionate to the cost of the company of undertaking the work," added Griffin.

Related: A guide to car insurance discounts