As the pound hit a 26-year high against the dollar last week, it emerged that some travel firms are still charging for theme-park tickets at year-old exchange rates – leaving families holidaying in Florida as much as £150 out of pocket.

Internet brokers say they are now undercutting high-street travel agents by as much as 25% on entry prices to Disney World and Universal Studios in Orlando.

One of the most popular buys for British tourists is Disney’s 14-day Ultimate Ticket, which allows unlimited admission to four parks plus other Disney attractions. It costs £168 for adults, and £148 for children aged 3-9, when bought direct from Disney.

A survey last week by The Sunday Times found the same ticket being sold by British Airways Holidays for £179/ £155 and by Virgin Holidays for £181/ £154. The highest prices we found were with First Choice – £189/£160.

Discount brokers were considerably cheaper. American Attractions (0871 231 3313, www.americanattractions.co.uk ) quoted £153/£133, while Theme Park Tickets Direct (0870 040 0210, www.themeparkticketsdirect.com ), which recently dropped its prices due to the weak dollar, was the cheapest at £147/£127. For a family of four, that’s a saving of up to £150.

Tom Samuel, the managing director of American Attractions, accused the high-street operators of overcharging. “For a simple product like a theme-park ticket, it’s hard to see how a travel agent can justify adding a commission of 10-15%,” he said.

Theme Park Tickets Direct admitted it was slashing its margins to stoke a price war. “These tickets are now cheaper to buy in the UK than in America,” said a spokesman.

Tour operators deny they are overcharging. They say they are forced to buy US dollars up to a year in advance to protect themselves against currency fluctuations. “Our hands are tied,” said one. “We effectively bought our tickets at an exchange rate of $1.85 and we can’t compete with agents who can buy them on the spot at $2.”

Virgin Holidays said it provided more security than internet brokers. First Choice said its prices reflected its higher overheads. It added that later this year it plans to set up its own online agency to sell discount theme-park tickets.

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