'Uncle Jimmy' celebrated his 70th birthday by giving out free ice cream to customers on March 22.

How would you celebrate your 70th birthday?

Ice cream vendor Jimmy Teng marked his special day on Tuesday (March 22) by giving his customers free ice cream.

"It's my birthday. My treat," he told customers at his stall outside Lavender MRT station.

Many customers were surprised. Some insisted that they pay for the ice cream. Others gave him a red packet.

And everyone wished the uncle a happy birthday.

Mr Teng, known affectionately by many as Uncle Jimmy, announced on his Facebook page the previous day that he would be giving out 700 servings of free ice cream to mark his 70th birthday.

It's my 70th birthday tomorrow! Come celebrate with me at my usual spot! 700 free ice cream to be given out! #unclejimmyicecream #70birthday #freeicecream Posted by Uncle Jimmy Traditional Ice Cream on wheels on Monday, 21 March 2016

But he prepared 1,000 servings instead, which would have cost him a few hundred dollars' worth of ice cream.

It was his way of "thanking all my customers for their support", he told The New Paper (TNP).

He has been selling ice cream at the same spot for the last 12 years just outside the ICA Building in Lavender, but this is the first time he has given out free ice cream.

And with every wish of "happy birthday", his smile grew wider and wider.

"I'm so happy," he said in Mandarin. "I wouldn't be this happy if I won the lottery!"

His happiness was shared by many around him, from young children who beamed at their treat, to working adults and senior citizens who were appreciative of the man's generosity.

Mr Ngu Yen Anh Tuan, 20, found out about the ice cream 'promotion' when he passed by Mr Teng's stand on the way to collect his student pass at the ICA building.

"He loves his shop," he said. "He can see people happily eating his ice cream.

"It's a small gesture, but I'm happy to receive it."

But this small gesture was just one of the many of Mr Teng's inspiring gestures.

Mr Haresh Vishinda, 45, sat in a wheelchair in front of Uncle Jimmy's ice cream stand, shouting to passers-by, "Free ice cream!"

Mr Haresh has been a regular customer of Mr Teng since five years ago and they became friends.

When Mr Haresh lost one of his legs two years ago due to diabetes, Mr Teng helped him get back on his feet by lending him money.

"He's supported me in many ways," said Mr Haresh, who is single. "When I'm sad, he'll cheer me up. When I've got a problem, he'll try to solve it.

"He has a good heart for the less fortunate."

In the past, Mr Teng would anonymously donate $1,000 every year to a community centre until he recently stopped to take care of his wife, who had a host of health problems.

He now lives with his 40-year-old daughter after his wife died last year.