February 29 will bring a multimillion pound windfall to the UK government, a motoring group claims.
The AA estimates that an extra day of commuting and the school run will bring in £56.3m of fuel duty from nearly 100 million litres of fuel sold.
This represents more than 0.2 percent of the £27.3bn the Treasury aimed to raise from fuel duty over the financial year.
AA president Edmund King said the extra day should ease the government's position in relation to the increase of 3.01p per litre in fuel duty scheduled for August.
"February 29 is a nice little earner for the government, particularly when the leap year creates an extra working day," he said.
"Obviously, the extra day's holiday to celebrate the Queen's Diamond Jubilee will cancel out some of the tax-earning benefit of the extra leap year day, but the four-day break in June should encourage an extra Christmas or Easter-level getaway.
"That is, unless stock market speculators have talked up Middle East threats, as they did last year, and pushed oil and fuel prices to a level that forces large numbers of drivers to stay at home and watch the celebrations on the telly."
The AA's comments follow recent campaigns by motoring groups calling for Chancellor George Osborne to cut fuel duty, arguing that it would boost the economy.
Fair Fuel UK presented a report to treasury minister Chloe Smith claiming a cut of 2.5p per litre would create 180,000 jobs in the first year at no net tax loss.
Osborne told Sky News that the he had already made concessions in his previous fiscal statements, meaning the duty was already 6p lower than it should have been.
Fuel duty stands at 57.6p per litre and the August increase will take it to 60.p per litre.