Simon Needham cuts a dashing figure as he drives through the streets of Los Angeles in his Jaguar XK8, by no means the quintessential Englishman abroad. At 41, this migrant millionaire is a rugged, designer-stubbled standard bearer for the latest bunch of Brits who have looked beyond our small island in the quest to grow their fortunes.

At 18, he took on Huddersfield with bright ideas and ambition. Today his creative agency Attik has offices in Leeds, New York, San Francisco and LA, and has recently been snapped up by Dentsu, a leading international ad agency, in a deal reputedly worth £40m. It may actually be more: by 2006, Simon and his co-founder James Sommerville were banking £20m-worth of contracts a year.

Attik develops brands through advertising, design and interactive media, and its client list today boasts buzzy names such as Adidas and Coca-Cola. In the buyout, Needham kept his job and his company kept its name. Consequently, he is more financially secure than ever, and his property portfolio includes houses in Beverly Hills and a three-bed pad in London beside Hyde Park. By his own admission, he is living the dream and, like a growing army of Britons, he has discovered that the grass in the cliché really is greener.

“I wake up in the canyons and the sun is shining every morning,” Needham says. “I absolutely love it here. It’s sad that I miss England so little, but I don’t. On my last trip to London, I saw about eight road-rage incidents during a one-hour drive. People are angry. It’s only now I know just how hard it is to live there.”

When he originally moved to California to help launch a new brand for Toyota, Needham found himself unwilling to return home not because of work pressures, but because he was smitten by the freedom and lifestyle that America offered. “Here, everyone wants your business,” he says, “and they do everything they can to please you. In England, you have to fit in.”

His fear is of sounding as if he’s gloating. “I’m not. I want my friends to come out here and see for themselves. Life in southern California is healthier, the weather means you want to be outside all the time, and within an hour I can be on the beach or snowboarding 5,000ft up a mountain. With the exchange rate right now, I can’t imagine there ever being a better time to leave Britain.”

Needham’s hunch is echoed by the Institute for Public Policy Research: it says more than 5m people born in the UK now live abroad, and their ranks are swelling. A study by the stat-cruncher Datamonitor also reports that 3.81m overseas properties are already owned by the British — excluding timeshares — and that every day, Brits spend £122m buying overseas property, a figure forecast to almost double by 2012. That’s a rise from £44 billion a year to more than £80 billion as the demand for bricks and mortar is fuelled in part by increased wealth.

Whatever the current financial thunderclouds threaten, it’s no coincidence that market-capitalisation growth rates — a primary driver of wealth generation — accelerated during the past two years and helped to increase the UK’s total number of high net-worth individuals (HNWIs have at least £25m in the bank). During the past year, the latest Sunday Times Rich List reports Britain’s millionaires growing 15% richer and, for them, tax changes might provide the incentive to move. Disposable household income doubled all round in the decade up to 2005, and when a populace enjoys greater affluence, mobility becomes easier — so exodus from this rainy land seems more tempting.

If upping sticks to move your business overseas was once perceived as intrepid, the era of global communications is the clincher that makes remote working truly feasible. In any case, if an HNWI has to abandon a venture that backfires, it may only involve some currency exchange and minor inconvenience.

For David Towells, an Oxford-based owner of a multi-million-pound recruitment business, leaving Britain never seemed much of a gamble. Selling his company was the life-changing part, and the move followed on after he and his wife Jacqui agreed that Britain could no longer meet their family’s needs. “We started looking at schools for the kids and soon became demoralised by the lifestyle that they might get into,” says Towells, now 46. “There’s the drink culture and the disappearance of community spirit. We wanted the children to be children a bit longer, and I wanted us to be able to go out after dark and not feel threatened.”

Towells says moving abroad is easier if you pave the way, taking short holidays to check for the right combination of lifestyle and opportunities. “First rent a house in the area you’d like to live, give yourself time to adapt and if things go well, find the house of your dreams and buy it.”

The reality is seldom so simple, as his family discovered when the Algarve proved a shade too sleepy and the local schooling somewhat lacking for his musically gifted children. Undeterred, they moved to Rome, where today father says they feel truly “at home”. Their 2,150 sq ft house in Portugal is on the market for £2.1m.