Red packets can be worth a lot these days, thanks to a growing community of collectors and traders who are driving up their value as design pieces.

Mr Arun Kumar, administrator of the Ang Pao Collectors group on online marketplace Carousell, told The Straits Times that membership stood at about 1,000 when he joined 11/2 years ago.

Today, the group has more than 4,000 members and counting.

"It's already grown by about 200 in the last week and I think it will keep growing till after the Lunar New Year," said Mr Arun, 30, who works in digital marketing.

"If you look through the listings in the group, you'll find a lot that don't follow the traditional colour or design any more, and that's probably why there are a lot of collectors around," he said.

Others use the platform to make a few dollars off the packets often given away as corporate branding tools by banks and businesses.

"Last year, I sold two packs in 10 minutes - the buyer drove all the way to (my) office to pick them up," said Mr Arun, who made $20.

A check by The Straits Times found that prices for hongbao listed for sale on Carousell range from a few dollars to $200 for a velvet red packet from Credit Suisse.

In contrast, traditional red packets are being sold for as little as $1 for a pack of six in Chinatown.

Designers and suppliers said that the hongbao is not simply red these days, but likely to sport bold colours and intricate designs or to be made from more expensive materials.

Craftwerkz manager Shirley Siow said: "We are now handling materials such as fancy paper, leather and satin. The decorating process has also become more complex - it used to be just printing and hot stamping, but now it's common to find three or more decorating processes in a single red packet."

These include embroidery, ultraviolet treatment and flock printing, which adds a velvet-like texture using textile fibres.

"The most elaborate red packet that we have done is for an ultra-luxury brand; it involved multiple decoration techniques such as embroidery, Swarovski crystal embellishment and stamping on satin material," said Ms Siow.

Corporate orders for Chinese New Year come in as early as March the year before, she added.

Ms Zee Lam, chief executive and creative director of design firm Concept Lab, whose past clients include Fullerton Hotel and the Singapore Exchange, said that brands are trying to stand out with more elaborate designs and packaging.

"Everyone tries to up the game with nicer finishings and luxe materials... Even with envelope design, now you have sleeves that can be removed so that the hongbao is in two parts," said Ms Lam.

Her firm's own zodiac-themed hongbao, which feature a different animal and colour scheme each year, have become sought after by collectors who call and sometimes even visit Concept Lab's office seeking to purchase them, she said.

Given the demand, Ms Lam said she is considering selling the series of 12 animal hongbao, completed this year, as a set and donating the proceeds to charity.

Kindergarten teacher Janicia Chong, 46, has grown her collection to more than 10,000 hongbao over the past 20 years.

While she liked the wider variety, Ms Chong lamented how collecting red packets has gone beyond a simple hobby.

People once collected hongbao out of interest, but there is a lot more buying and selling these days.

"Now, it is like a competition to see who can get their hands on the better brands," said Ms Chong.