The bargain price for a week in Orlando includes car hire. Travel firm Going Abroad Travel said it had been forced to take drastic action because interest in the forthcoming European football championships had brought the package holiday market to a near standstill.
Public relations officer John Slade said the firm had "hundreds" of seats available at pounds 49 for one-week holidays throughout June. "There's already over capacity in the market to Orlando," he said.
"Laker's started flying there. There are a lot of people flying there. It's an extremely popular destination. But there's no question about it, Euro 96 has meant package holidays just aren't moving. This is what it takes to shift it."
Mr Slade said people began snapping up the offer as soon as it went on sale at 9.30am yesterday. The seats, with further cut-price two- and three- week holidays, are expected to sell out in the next few days.
The full scheduled airfare to Orlando is pounds 339 return with car hire a further pounds 69 a week.
News of yesterday's offer came only a few days after a family from Doncaster snapped up a pounds 9-a-head fly-drive break in the sunshine state. They bought the holiday after seeing it advertised as a last minute cancellation on Teletext.
The Association of British Travel Agents (ABTA) confirmed that some operators were left with extra capacity in the Florida market for June but said July and August were almost fully booked.
It is the only location for the British package market not to have had availability cut after last summer's vicious holiday price war. Then customers were staying at home because of the hot summer.
Jackie Gibson of ABTA said: "I have spoken to the Florida Office of Tourism and there seems to be quite a lot of space available. But we don't really know why that is.
"As for the rest of the market it is pretty much as expected. Over the Bank Holiday weekend a lot of people wanted to go away after the gloomy weather and because the school half term followed. Extra seats were booked particularly for the Balearics and Tenerife.
"But people need to check that there are no hidden costs or strings attached. When operators are discounting so heavily, they may quite legitimately want you to buy their insurance."