Depending on my research, the final HDB hotline is 1800-225-5432 . It's a Branch Business Services Line that operates on weekdays from 8:00 AM to 5:00 PM.Also, there are other Make contact with figures for distinct expert services:* HDB Most important Line: 6490-1111 (for common enquiries, weekdays 8:30 AM - five:00 PM)* Essential Maintenance S