You walk in, you ignore the odd bit of dust and the sometimes shabby decor and you rootle through racks of old coats and clothes — in search of gold. A bargain, thrown out by someone who no longer needed it and put on a hanger with a ludicrously low price tag that no sensible person could ignore. It is one of the secret joys of shopping, but it seems that it is, increasingly, a secret no more. Charity shops are coming into their own.

Far from the clinical, corporate, shiny, sterile high-street chain, the small, idiosyncratic home of the hand-me-down is enjoying a recessionary revival. Squeezed for cash, needing to make every pound and penny count, shoppers are spending money on good causes, whether intentionally or not, in growing numbers.

And those numbers tell a clear story. While sales have fallen at the likes of Marks & Spencer and Next, the British Heart Foundation (BHF) and Oxfam have reported like-for-sales growth of 5 per cent or more in January and March (sandwiching a snow-covered blip in February) and Cancer Research UK says that its underlying sales growth hit 10 per cent during the same period. Overall, the Association of Charity Shops says that its members' sales rose between 3 and 5 per cent in January and a similar trend is expected for March.

“Charity shops are the natural option for people looking to save money but who want good-quality goods,” Ken Blair, chief executive of the British Heart Foundation's stores, said. “There is a big difference between charity shops and the discounters [the other big winners in the credit crunch]. We sell good-quality goods at low prices, not cheap goods.”

Given such a fertile economic climate, charity stores are looking to brush up their acts. Already, some of the bigger chains are reaping the rewards for improving their store layouts. Mary Portas, a fashion retail expert, hopes to spread the message to a wider audience in her new television series, starting in June. “There is both a financial and environmental crisis going on,” she said. “If the charity shops can harness the impact of those two issues, then that is a powerful position to be in on the high street.” However, she added, too often charity shops still “look like hell” and struggle to find good stock. As much as 75 per cent of donations are not suitable for the shop floor. Indeed, many charitites struggle to get decent stock. The BHF has increased house-to-house collections by 15 per cent since Christmas, but excluding the impact of its ramped-up collection service, there has been a 25 per cent slide in donations in the past 18 months, it said. That decline has accelerated in the past six months.

Getting good stock is crucial, David McCullough, deputy chief executive of Oxfam, said. He argues that the main driver of sales growth within Oxfam's stores has been better stock, not a switch by high street shoppers to charity shops. Oxfam's deal with Marks & Spencer — whereby those who donate goods that include at least one M&S item receive a £5 voucher to spend in the high street store — has boosted sales by at least £2 million in the first year.

The deal has also attracted interest from fashion magazines, such as Marie Claire, eager to show its readers how to create their own individual style from charity shop finds — something that has been a staple of charity-shop-shoppers since the Sixties.

Other charity chains are stepping up their efforts to get better stock. Cancer Research UK has launched its second celebrity-fronted campaign since Christmas, in an effort to arrest sliding second-hand good donations. It has signed up Tara Palmer Tomkinson and Mark Foster, the Olympic swimmer and Strictly Come Dancing star, for a campaign to urge people to donate more to its stores. It also intends to repeat its venture with TK Maxx, the clothing chain, in which shoppers could drop off clothing donations in-store.

Charities have also been hit by the rise in commercial clothing collectors, who can misrepresent themselves as charitable enterprises. Such companies make their profit by selling clothing donated in the UK overseas. Competition is likely to get more intense in the months ahead. According to Mr Blair: “A lot depends on whether the public have the goods to donate and it is going to get tougher as time goes on and the recession bites.”

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