It was also found that people in the south-east are the most likely to have never visited a foreign country.
Neil Laird, travel insurance manager for Sainsbury's Finance, said: "British people often holiday in the UK, whether it be their main get-away or a short break or long weekend.
He added: "Many of the problems that you can encounter abroad can also happen here in the UK on holiday, so it is important to ensure that you have adequate cover."
Previous research by Sainsbury's Bank found that over a million people have admitted to driving without insurance in the past 12 months.
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