There are quite a few local Singapore couples and expats living in Singapore that are very much into swinging and swingers parties, but they are private about it.
There are two main swingers clubs in Singapore, and another few private swingers groups that have regular swingers parties in Singapore.
The two main swingers clubs that run regular parties are:
• United SG Swingers
• Singapore Inner Circle
There are regular private house parties and meetups at classy hotels around Marina Bay Sands area, but they are by invitation only. You can find out more about them by joining swingers sites like RedHotPie Asia.