Australians will well remember the slump that followed the Sydney Olympics, while many other host cities have failed to realise the tourism bonanza they expected from the event.

London has many things playing in its favour and operators are reporting strong bookings for coming months.

It is impossible to pinpoint what is Olympic-generated interest and what is travel that would have occurred anyway, but London is building on a dream run including the royal wedding and Diamond Jubilee, which have kept the city at the forefront of travellers' minds.

Britain also has a history of quality tourism promotion and has no doubt benefited from the painful lessons of other host cities.

VisitBritain says it has embarked on its biggest ever marketing program, spending about £35 million ($52.7 million) over 18 months to promote Britain in overseas markets.

The organisation is working with airlines, hotels and tour operators to convert the Olympic profile into holiday bookings. "We know that the tourism legacy of hosting the Games is not a given and needs to be worked for," says the chief executive of VisitBritain, Sandie Dawe.

The executive general manager marketing for Flight Centre, Colin Bowman, says the timing is favourable for London to continue the momentum of the Olympic Games, which highlighted a range of venues and attractions from the City of London to the Dorset coastline.

"One thing they have going for them is that it is still the traditional high season for London," Bowman says. "I think some people did postpone their travel plans and are going to go in September or October, when the weather is still reasonable. We are certainly going to push hard; there's an opportunity to capitalise on the great perception of London that has been created by the Games." Bowman says the period of pent-up demand will be followed by the traditional early-bird sales season, in which airlines and other operators release specials for travel in 2013.

"I think the halo effect is still going to be with us then," he says.

"It's reasonable to expect there should be good demand for some time."

Virgin Atlantic says its year-to-date passenger numbers from Sydney to London are up 50 per cent on last year, for both economy and premium seats.

The general manager, Luke Fisher, says the Olympics have combined with other high-profile British events, a high Australian dollar and the airline's joint promotions with VisitBritain to generate the traffic.

"[This is] the year for Britain; the country has had some fantastic reasons to visit," Fisher says. "Not to mention what it normally has to offer, with its amazing history, culture, food and shopping."

While the airline would normally expect a post-Olympics drop in bookings to a host city, its forward bookings for travel to London show year-on-year growth of 7 per cent to 8 per cent.

Travel.com.au says it has had a surge in bookings for the period after the Olympics, with many travellers holding off until the Games had finished. Of all flights booked for travel between mid-July and the end of October, nearly three-quarters were for the post-Olympic period.

"Many of our customers have chosen to wait until after the Olympics," says the general manager of travel.com.au, Renee Welsh.

Welsh says she is not expecting interest to wane, with the Olympic profile adding to what was already a popular destination.

"London consistently remains in our top three destinations, month-on-month," she says.

Webjet says it is also seeing strong forward bookings for post-Games London, with the upcoming early-bird sales season expected to stimulate further demand.

The company experienced exponential growth in bookings to London in the first half of the year, with sales only dropping off when seat availability and pricing became an issue in the lead-up to the event.

STA Travel says some accommodation suppliers in London have been feeling an immediate post-Olympic slump, with occupancy levels low.

This has led to great deals for those wanting to travel now, according to STA Travel spokesman Reuben Acciano.

Acciano says London is very much an "in" place for the younger market, especially as it has become more affordable due to favourable exchange rates.

It is a destination that is not limited to its association with any one-off event, he says.

When to go?

If London has grabbed your interest, pick your timing to get a good deal on flights.

Fares should get cheaper from September to November, then they will peak for Christmas and New Year.

February is usually the worst month in terms of weather, but March to May is a good "shoulder season" option, with milder weather and spring flowers.

If you want to travel in the peak months from June to August, the best bet is to pick up an early-bird special, with deals due to be released over the next two months.

jane@janeefraser.com.au