Nine men and 34 women were arrested on Tuesday evening, after a police operation against a vice syndicate in the area from Lorong 29 to 35 Geylang.
The suspects, aged between 18 and 65, were arrested at a terrace house in the Joo Chiat area.
During the operation, police seized the syndicate's records, several SIM cards, cash worth about S$50,000 in Singapore and foreign currencies, and a saloon car believed to be used to ferry vice workers.
If found guilty, the suspects could each be fined up to $10,000 or jailed for up to five years, or both.