They are the boomerang migrants. Thousands of Australians who settled here are returning down under to escape the UK’s economic slowdown and its spiralling cost of living.

The Australian authorities have seen a 50% jump in the number of their citizens returning home from Britain since the credit crunch last summer.

Experts say that rising numbers of migrants from Poland, India and Nigeria are also quitting the UK for better jobs and the hope of a higher standard of living back home. Analysis this weekend has shown that the cost of running a family has grown by more in Britain than in any other country in the western world.

The exodus of foreign workers is already harming the building industry and causing alarm in the Square Mile. According to figures kept by the Australian government, 2,600 of their citizens have been returning home each month since last June. That compares with 1,750 a month between 2000 and 2005. Many Australians have been enticed back to their homeland by job opportunities created by a punchy economy that has grown by 3.6% over the past year.

The impact is likely to be much more serious than in previous decades when many Australian migrants to Britain were young travellers content to pull pints. The majority of Australians working in the UK are now employed in financial services and other professions, according to TNT, the magazine for Australians working in Britain.

Jason Cartwright, a director of Link Recruitment, an international employment agency, said the UK was already suffering a “brain drain” of Australian workers from the City. “In the UK’s financial services sector, hiring freezes are increasingly common – but opportunities abound in the Australian market,” he said. “There is also a belief that Australia is a safer bet while the credit crunch runs its course.”

By contrast, City firms in London are expected to shed 6,500 jobs this year, with the economy predicted to grow by 1.7% – its lowest rate since 1992. On Friday, official figures showed that economic growth halved to 0.3% in the first quarter of this year. The Australian dollar hit an 11-year high against the pound in May, meaning Australians’ sterling earnings have fallen by 21%in dollar terms over the past year.

Wiriaya Plukavec, 31, came to London from Sydney two years ago to work as a credit controller in the City. She plans to return home in the next few weeks. “I was going to stay another year but just got fed up with the cost of everything going up – bills, food, toiletries, rent, going out – everything,” Plukavec said. “Life will just be a whole lot cheaper back in Sydney . . . and the weather will be better.”

Chris Hurd, an Australian film-maker, returned to Sydney three months ago after a decade in Brighton. Hurd, 45, and his wife found new jobs easy to find. “We could never have raised a family in London – the cost is prohibitive,” he said. “You can’t get a rudimentary education in England without paying a fortune.”

Nicola Brennan, 35, moved back to Melbourne earlier this year after 10 years working as an accountant for an investment bank. “My husband and I decided to return to Australia because we felt it was a much better place to start a family,” she said.

Research published this weekend by the Economic Research Institute think tank shows that the annual housing, food, travel and other costs of a typical middle-class family of three in London has soared to £38,880 – an increase of £2,160 in four months, a bigger rise than in any other main western city. The same standard of living now cost £32,706 in Sydney and £28,664 in Los Angeles.

There are no precise data on the number and nationality of migrants who have left over the past year; however, the Institute for Public Policy Research, the left-leaning think tank, has surveyed hundreds of migrants of all nationalities about their plans to leave. It calculates that half of the estimated 1m Polish plumbers, builders and other labourers who have arrived in Britain over the past four years have now returned home.

Britain’s worsening economic climate is expected to drive more migrant workers back to their homelands. The cost of all foods have risen by an average of 6% this year, but the price of staples such as milk, butter, eggs, pasta and bread have risen by as much as 60%. Petrol prices have risen by 22%.

Government figures published on Friday showed that British savers tucked away £2.6 billion in the first quarter of this year – down from £7 billion on the final three months of last year.

Additional reporting: Anna Mikhailova

Growing exodus

2,600 Australian migrants are quitting the UK each month, up from 1,750 a month in 2005

13,800 Australians applied for visas to work in the UK during 2007, half the number of applicants during 2005

125,000 Polish migrants are expected to return home this year, a fourfold increase on 2006

206,000 British citizens emigrated last year, a 45% rise on 2002

179,000 foreign nationals living in the UK returned home last year – up 13% on 2002

75% of NHS doctors who deregistered last year were foreign nationals

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