Whether you have a depressingly meagre clothing budget or a huge amount to spend on fashion, chances are you love a good bargain. And, increasingly, what we also demand from our wardrobe is a sense of individuality — the sort of unique, one-off piece you can flaunt, knowing you will be the only one walking down the street in it.

So, where to go to combine these fashion prerequisites? Surprisingly, that place is a jumble sale — two words that, if we’re honest, conjure up notions of fusty, forgotten knits, musty village halls and, frankly, everything that fashion is not. Yet, the humble jumble sale has been given an almighty shake-up by the young and fashion savvy, and it’s even getting Britain’s best-dressed celebrities out of bed on a Sunday morning. For them, this is the antithesis of intimidating boutique shopping.

Capturing this new consumer mood, and adding a dash of glamour, is Selfridges. The model Lisa B will be taking over the first floor of its car park for the Really Really Great Garage Sale next Sunday, in aid of her charity, Mothers4Children. Jemima Khan, Yasmin Le Bon, Louise Redknapp and Trinny Woodall will be among the stallholders selling their cast-offs (including a Helmut Lang suit from Liz Hurley and a Versus dress from Claudia Schiffer). Rumours are circulating that Le Bon’s stall will be the hit of the day. “I’ve taken on two stalls because I’m selling some of Simon’s stuff. There will be some incredible pieces,” she says.

The garage-sale concept is a far cry from the usual black-tie celebrity fundraiser, but it suddenly feels right, says Lisa B. “It’s a sign of the times. People love the idea of finding something unique when they have to be more concerned about their spending.” What does she have her eye on? “Jemima Khan’s fabulous dresses — a beautiful one by Prada and a Diane von Furstenberg.”

Ramping up the glam factor in equal measure is Harper’s Bazaar, which will host Gladrags & Handbags, a designer fashion sale starting on Friday, in aid of the charity Kids Company. Expect to find clothing and accessories at the Music Rooms, W1, donated by fashion’s big names, at a fraction of the original price.

The new jumblistas are breaking out of church halls and setting up home in trendy bars, complete with a DJ or band, cupcakes, cocktails and, crucially, a highly covetable selection of stock. “The stigma attached to second-hand clothes disappeared a long time ago. Everyone loves vintage, but it can be expensive. Jumble sales are cheap,” says Karolina Hedstrom, who runs Wills-Moody, the rock’n’roll-themed jumble sale in London. The price is right and the spending is virtually guilt-free, but what of those fusty knits? “We sell clothes you actually want to wear. It’s not how jumble sales used to be, it’s more like peering into your friends’ wardrobes,” Hedstrom says.

Choose your jumble sale wisely and you won’t have to sift through tons of rubbish to get a killer high-end piece. “We buy stuff in to sell, but it’s got to be different from what you would see on the high street. It has to be special,” says Rosalia Ferrara of Jumble & Pearls, the Islington-based jumble sale that has had local fashion addicts in a frenzy since it began a year ago. “It has been such a success, we’re talking about holding sales outside London — Jumble & Pearls on tour.” Though the prices are modest, Ferrara suggests haggling, too — you might just bag your best designer bargain yet. “We’re all a bit soft. I caught one girl selling a Marc Jacobs bag for £10.”

What really sets this new raft of jumble sales apart is the social aspect. The modern-day jumble feels more like being at a cool party than just a gloomy rummage through old clothes. And it isn’t just the capital that has taken the jumble-sale ethos to its heart. Matt Aitken is the promoter for the Jumble Sale at Start the Bus, a music venue in Bristol, which invites local art students to sell their wares. “It started off as just a student thing, but now we get all ages. It has evolved into a big social event, a place to hang out for the day.”

So, what are you waiting for? A brand-new shopping experience awaits.

Where to rummage

London The Really Really Great Garage Sale, Selfridges (next Sunday); selfridges.com . Gladrags & Handbags (Friday-Sunday); kidsco.org.uk . Wills-Moody; willsmoody.com . Jumble & Pearls; search for Jumble & Pearls on Facebook.

Manchester Sand Bazaar Jumble Sale; 0161 273 1552. A sale with a creative vibe: arts, crafts and cakes. The next one is on Wednesday.

Bristol The Jumble Sale; startthebus.tv . There’s something for everyone — records, clothes, books, games and bric-a-brac galore. Runs the third Sunday of each month.

Glasgow Rumble in the Jumble; 13thnote.co.uk . The sale takes place on the last Sunday of each month, with an emphasis on vintage clothes, jewellery and accessories.

Bournemouth Rumble in the Jumble; sixtymillionpostcards.com . You’ll find arty bric-a-brac, courtesy of the local art students, with retro film showings and acoustic music. First Sunday of the every month.

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