| 421 | Oncology Centre The
| Active |
| 422 | Oser Design Pte Ltd 199305979N | Active |
| 423 | Origin Jetters 45453200L | Active |
| 424 | Osi Electronics Pte. Ltd. 200604568C | Active |
| 425 | Olympia Printing Pte Ltd 199608621Z | Active |
| 426 | Original Sin By Michelangelo's 52841204C | Active |
| 427 | Original Media Pte Ltd
| Active |
| 428 | Ong Boon Seng Pte. Ltd. 200001699N | Active |
| 429 | On Cheong Jewellery
| Active |
| 430 | Orix Capital Ltd
| Active |
| 431 | Oshika Singapore Pte Ltd 198104636W | Active |
| 432 | Ondori Pte Ltd
| Active |
| 433 | On Demand Contract & Svcs Pte Ltd
| Active |
| 434 | Orexis Trading Pte Ltd
| Active |
| 435 | Ong Ban Hong Leong (Pte) Ltd
| Active |
| 436 | Omeio Int'l Pte Ltd
| Active |
| 437 | Orion Worldwide Pte. Ltd. 200502895N | Active |
| 438 | Oliver Dental Surgery Pte Ltd 199501028K | Active |
| 439 | Oltec Pacific Center Pte Ltd 199703670N | Active |
| 440 | Outdoor Life Pte. Ltd. 200700158H | Active |
| 441 | Oub Centre Ltd
| Active |
| 442 | Otto Furnishings Pte. Ltd. 199707395R | Active |
| 443 | Otto Marine Ltd
| Active |
| 444 | Oto Bodycare Pte. Ltd. 198303351R | Active |
| 445 | Orix Rentec (S) Pte Ltd
| Active |
| 446 | Osim Int'l Ltd
| Active |
| 447 | Orthopaedic Associates 50766600C | Active |
| 448 | Orthopaedic & Traumatic Surgery Pte Ltd 198601575M | Active |
| 449 | Orthopaedic Surgery James Lee
| Active |
| 450 | Orthopaedic Practice Pte Ltd 198804556N | Active |