| 631 | Offshore Seals (Asia) Pte Ltd
| Active |
| 632 | Oriental System Interior Pte Ltd 198200002G | Active |
| 633 | Onebuilder Pte. Ltd. 200305666Z | Active |
| 634 | Op3 International Pte. Ltd. 200619019R | Active |
| 635 | Oneberry Technologies Pte. Ltd. 200312911N | Active |
| 636 | Only Marine & Construction 53054074J | Active |
| 637 | Outdoor Specialist Pte. Ltd. 200306667G | Active |
| 638 | Ong & Koh Services Enterprise 26587600A | Active |
| 639 | Oil & Gas Solutions Pte. Ltd. 201011879C | Active |
| 640 | Or Thiam Hock General Contractors 50935200J | Active |
| 641 | On Theng Shin Construction Company 22405800B | Active |
| 642 | Oceanlec Pte. Ltd. 200717077C | Active |
| 643 | Ocean Enterprise Pte. Ltd. 201021329D | Active |
| 644 | Orapi Applied (s) Pte. Ltd. 198501879R | Active |
| 645 | Ow Bee Aluminium Works 34258500B | Active |
| 646 | Oh Lian Huat Contractor Pte. Ltd. 200209216Z | Active |
| 647 | Octagon Development Pte. Ltd. 200210070M | Active |
| 648 | Oshi Engineering Pte. Ltd. 201018736W | Active |
| 649 | Ottawa Interior Decoration 31125400D | Active |
| 650 | Oil Tech Engineering Pte. Ltd. 200400101W | Active |
| 651 | Oceantalk Pte. Ltd. 200806814W | Active |
| 652 | Oasis Projects Pte. Ltd. 200908308M | Active |
| 653 | Okada Mcs Pte Ltd 199902398N | Active |
| 654 | Ocl Construction Pte. Ltd. 200803666E | Active |
| 655 | Oriental Constitution Material Decoration Pte. Ltd. 200612281M | Active |
| 656 | Ong Teng Chong Building Contractor Pte Ltd 198801389G | Active |
| 657 | Ocean Blue M&e Pte. Ltd. 200614789E | Active |
| 658 | One Creation (pte. Ltd.) 200615660D | Active |
| 659 | Orchard Shenton Facade International Pte. Ltd. 200619478Z | Active |
| 660 | Ong & Ong Pte. Ltd. 199204938M | Active |