SINGAPORE - If you have not used your ActiveSG dollars, you have one month left to extend the $100 in credits for another year.

ActiveSG was launched in April 2014 to encourage more citizens and permanent residents to live a healthy lifestyle.

According to March 2016 figures, there were 1,011,529 ActiveSG members.

All members, upon signing up, are eligible for the complimentary $100 ActiveSG credit. More than two-thirds have utilised their free credits.

The credits can be used at Sport Singapore facilities, including swimming pools and gyms. They can also be used to book sports facilities and to pay in part for ActiveSG programmes and activities.

For members who signed up but did not use their credits, the credits will expire by the end of the year.

But they can extend the validity of the ActiveSG dollars by performing a transaction on the ActiveSG website or app. Users must have made a transaction before Dec 31 this year, to extend the validity of their dollars until Dec 31, 2017.

Users who signed up before Jan 1 this year and have made at least one transaction at any point will automatically have their ActiveSG dollars expiry date extended to Dec 31, 2017.

Members received e-mails this month reminding them to use the ActiveSG dollars.

"We encourage you to keep active and make full use of your ActiveSG Dollars. Simply perform any Web or app transaction, or scan-in to any of our 26 swimming complexes and 16 gyms islandwide today to extend the validity," the e-mail said.

Here's the ST guide to using your ActiveSG dollars.