Headwear, from chic pillboxes to over-sized clip-on bows, is no longer just for weddings and christenings.

Delightful, impractical hats were all over the spring/summer 2008 catwalks; Oscar de le Renta’s models sported tiered feather hats at New York Fashion Week and Giles Deacon sent his girls out with candy-coloured confections on their heads in London.

It’s not just a catwalk trend; hats have long been the finish to a girl’s outfit in the burlesque and cabaret scene, with its emphasis on old school Hollywood glamour. After the scene went mainstream, thanks to Dita Von Teese, it was only a matter of time before hats moved out of special occasion boxes and onto the heads of women shopping in Waitrose.

Sarah Jessica Parker, who single-handedly revived the prom dress, wore a Philip Treacy number to the premiere of Sex & the City and it’s reasonable to assume high street fashion stores will be handed over to hats of the frill, feather and net type very soon.

Selfridges and Harrods say hat sales always increase in the lead up to summer with women buying for weddings, christenings, Ascot and Henley. However, according to Harrods’ assistant buyer for millinery Danielle Brown, this year women are buying smaller hats.

“Fascinators (hats with a net veil attached) are an increasingly popular choice and a fantastic alternative for ladies who do not want to wear a large hat,” she says.

“We've been selling hats which feature interesting details such as twists, swirls and roses and small hats worn on the side of the head (referred to as a beano or slice hat) are extremely sought after.”

Harrods stock a number of desirable designers including Philip Treacy, Siggi Hats, Philip Somerville, Peter Bettley, Marzi and Nerida Fraiman.

Fraiman, who trained with Philip Treacy, designs wonderful cocktail hats that work for dinner or a day at the races.

“Hats add that touch of glamour, they are like jewellery for the head,” she says.

“That’s why I particularly like working with feathers as the colours are fantastic, but also they move beautifully and are quite sensual. I love it when I’m out and I see someone wearing one of my hats, I think it’s great they are not being kept in a box waiting for a big occasion.”

As added encouragement to break out the hatbox, London hotel The Langham is offering complimentary Laurent Perrier champagne to all ladies who wear an elegant hat while taking afternoon tea or lunch at its restaurant The Landau until July 6.

Restaurant manager Franco Becci says the idea is to give women another opportunity to show off their fantastic hats.

“At The Landau we are all for a little elegance,” he adds.

“Why must all the best hats be saved for Ascot week? Let’s make this the summer hats came back to the West End.”

If you want to wear a hat for lunch with the girls or on an evening out, then vintage styles are particularly wearable, whether original or a beautifully made copy.

Tim Sanderson, owner of vintage boutique This Shop Rocks on Brick Lane, London, says demand for hats has been increasing steadily over the past 18 months but in the last four, sales have shot up. Sanderson sources the majority of his hats from America, and prices start at around £50.

“The most popular style is the fascinator but women are also asking for cloche hats [from the 1920s] as they are more wearable during the day,” says Sanderson, who devoted his window display to hats in May.

“The important thing is to wear the hat, not let the hat wear you. You have to be bold.”

Milliner Tricia Cox, who makes hats from vintage patterns, says she wouldn’t feel dressed without one of her creations poised upon her head.

“Hats make you feel special, today so few women wear them that immediately you stand out,” she says.

“And people are so much more gracious and friendly towards you. Men offer up their seats on trains and buses. But I do advise making sure your hat is securely fitted, I have on occasion had to chase one of mine down a road, and running in heels is not the safest activity.”

Times recommends

• It is possible to look stylish while pregnant
• Britain’s tot models
• Who and what benefits from the heat wave?