The Singapore Sweep is changing.

From today, the lottery tickets will no longer be pre-printed with thematic designs, and punters will have the opportunity to buy tickets with some numbers of their choice.

Sweep tickets purchased at Singapore Pools outlets will be printed on demand, and customers should use the 4D bet slip or approach counter staff to choose via "quick pick".

The new selection formats allow players to choose either the first or last four digits of their set of numbers, but not both. Every ticket has a seven-digit number.

Singapore Pools is also introducing another new format called 100 Sweep, which will allow punters to buy 100 sets of numbers in running sequence, with the last two digits ranging from 00 to 99. This will be printed on just one ticket slip.

One set of 100 Sweep tickets, for example, will have numbers ranging from 1234500 to 1234599.

Besides the new selection formats, tickets will have a new look.

They will no longer feature the thematic pictures centred around communities, nature and iconic landmarks. Instead, the tickets will be printed on thermal paper in black ink, much like current 4D and Toto tickets.

"This change is part of Singapore Pools' efforts to go green through reduced paper usage, and to streamline operations for efficiency and productivity," said a Singapore Pools spokesman.

There is no change to the game play and prize structure, and there will continue to be 3.5 million sets of seven-digit numbers for sale, with each set sold at $3.

The change would also reduce costs as there would no longer be the need to upgrade and maintain a separate ticket inventory system and handle delivery of the pre-printed Sweep tickets to the various outlets, said the spokesman.

"All these are part of our ongoing efforts to increase productivity and efficiency so that cost savings can be channelled for community benefit and in support of worthwhile causes," said the spokesman.

She said Singapore Sweep ticket vendors, such as mamak shops, magazine stands and petrol stations, will still be able to sell tickets that will be printed in the new format and delivered to them.

Most punters contacted by The Straits Times said they were looking forward to the changes in the Singapore Sweep, even though they usually bet on 4D and Toto.

"When you can't choose any of the seven numbers, it is harder to win. But I might have more luck with numbers of my choice. I might go back to buying them," said Mr Koh Yang Nguan, a contractor. The 56-year-old used to buy the tickets once every few months, but stopped in recent years.

Other regular players, including a 54-year-old manager who wanted to be known only as Mr Wong, were also excited by the change.

"It is a good move. I can now buy my favourite numbers instead of choosing from the limited tickets available at the outlets I frequent.

"Even though the odds of winning are very low, I look at it as just a punt and more (as a way) to contribute towards charity," Mr Wong said.

Pre-printed Singapore Sweep tickets first came onto the scene in 1969, with a different ticket design for every monthly draw.

Each ticket cost $1 at the time and the first prize was $400,000, which gradually increased to $2.3 million today.