| 1921 | Origin Energy Geothermal Holdings Pty Limited
T10UF1018C | Active |
| 1922 | Oriental Supply Pte Ltd
199506057Z | Active |
| 1923 | Ohmsound Pte. Ltd.
201607064Z | Active |
| 1924 | Orange Seed Holding Pte. Ltd.
201607220N | Active |
| 1925 | Ozura Interactive Sdn Bhd
T10UF1152E | Active |
| 1926 | Ordino Investments Pte Ltd
199505406G | Active |
| 1927 | Originex Networks Sdn Bhd
T10UF0226G | Active |
| 1928 | One Global International Limited
T11UF4514G | Active |
| 1929 | Oilmac Engineering & Services Pte Ltd
199800613E | Active |
| 1930 | Oaktree Properties Pte Ltd
199605121W | Active |
| 1931 | Orientdeal Pte. Ltd.
201503459K | Active |
| 1932 | O.e.b. Properties Pte Ltd
199603606G | Active |
| 1933 | Oaktree International (hk) Limited
T16UF1834J | Active |
| 1934 | Okada Ecotech Pte Ltd
199805584M | Active |
| 1935 | Occident Technologies Pte. Ltd.
199605108H | Active |
| 1936 | Ocean Fine Pte Limited
199606217C | Active |
| 1937 | Odyssey Maritime Pte. Ltd.
199606151M | Active |
| 1938 | Orion Consulting Pte Ltd
199702382H | Active |
| 1939 | Octet Pte. Ltd.
200814208G | Active |
| 1940 | Oaklands Engineering Solutions Limited (08038781)
T15UF3308L | Active |
| 1941 | Orient Giant Group Limited
T15UF3235C | Active |
| 1942 | Octo Tech Precision Pte Ltd
199608502K | Active |
| 1943 | Ocean Oriental Singapore Pte Ltd
199900992D | Active |
| 1944 | Oilim Global Synergy Pte. Ltd.
201221688Z | Active |
| 1945 | Ocean Power International Pte. Ltd.
200617066N | Active |
| 1946 | Oculex Asia Pharmaceuticals Pte Ltd
199508301G | Active |
| 1947 | Ong Chin Lee Construction Pte Ltd
199400342N | Active |
| 1948 | Ong Kee Gee Holdings Pte Ltd
199602204K | Active |
| 1949 | Openix Pte Ltd
199605756W | Active |
| 1950 | Ocs Training Institute (singapore) Pte. Ltd.
201530548G | Active |