Parents will shell out £60 just on bottled water, during days out this summer.

The average family will make eight day trips, purchasing three bottles while out and about, at a typical price of £2.50. A fifth even plan to take their children on more than 15 day trips this summer, which could cost more than £112.50.

The survey, of 1,000 parents with kids aged 0-17, found 66% reckon buying water at attractions is overpriced.

Terri Cooper, from mineral water brand Aqua Pura, which commissioned the research, said: “Family days out are about having fun and making life-long memories, but the costs can easily add up.

“Having a car-boot filled with all those essential family trip items like suncream, extra snacks, spare clothes for the kids, games, a rug and a big pack of bottled water is a brilliant hack.

“It helps keep budgets down and avoid costly drinks runs.”

Parents blame a lack access to water fountains (39%) for their reliance on buying water on the go, and a quarter (26%) of parents distrust the water quality at refill stations when they do find them.

One in four (24%) of parents find shared water fountains and refill stations unhygienic, and 12% of children outright refuse to drink from them.

Terri Cooper, from Aqua Pura, added: “There are a number of hacks parents can deploy to avoid issues like this, and it definitely pays to buy ahead.

“My top tip to maximise family days out on a budget is to plan ahead – it doesn’t take long to fill your car boot with all those family essentials.

“Make your own budget-friendly snacks and stock up on £5 kids activity games that can be kept in the car, and the whole family can stay entertained and hydrated all summer.”