Determined by my research, the final HDB hotline is 1800-225-5432 . It is a Branch Place of work Assistance Line that operates on weekdays from eight:00 AM to five:00 PM.On top of that, you will find other Speak to figures for distinct expert services:* HDB Most important Line: 6490-1111 (for general enquiries, weekdays eight:thirty AM - five:00