The following list shows all the companies that are in the game.
| Companies List | |||
| Pos. | Company Name | Awards | Total Worth |
| 12801 | One Shot | £ 123,851,456 | |
| 12802 | One Silence | £ -4,074 | |
| 12803 | One to Many. | £ 4,976,234 | |
| 12804 | One United | £ 5,379,005 | |
| 12805 | one1 | £ 3,058,084 | |
| 12806 | OneNation | £ 45,456 | |
| 12807 | oneone | £ 18,206,569 | |
| 12808 | Oner | £ 10,516,756 | |
| 12809 | OneStopEnvelopeShoppe | £ -38,952 | |
| 12810 | Onion of Arabia | £ 11,458,256 | |
| 12811 | Onioninc | £ -43,613 | |
| 12812 | Onions | £ 56,031,337 | |
| 12813 | onions inc | £ 46,832,459 | |
| 12814 | ONLINE GAMES | £ 120,242,830 | |
| 12815 | Only Bombs Allowed | £ 57,741,277 | |
| 12816 | Only Fools and Horses | £ 859,719,219 | |
| 12817 | only me | £ 50,000 | |
| 12818 | only me inc | £ 133,078,068 | |
| 12819 | Onomatopoeias | £ 939,660 | |
| 12820 | Onshore Money | £ 104,918,400 | |
| 12821 | Ontara | £ 79,736,570 | |
| 12822 | Ontario | £ 85,260,376 | |
| 12823 | ontheblock | £ 6,402,837 | |
| 12824 | Onyx | £ 429,592 | |
| 12825 | OO7 | £ 55,808,206 | |
| 12826 | Ooglaigh na Heireann | £ 240,713,877 | |
| 12827 | oohyeaa | £ 50,844,745 | |
| 12828 | Oolacile-01 | £ 2,954,344 | |
| 12829 | oOoOo | £ 248,934,291 | |
| 12830 | oooooo | £ 5,505,528 | |
| 12831 | OOOoooOOO | £ 614,697 | |
| 12832 | oooPPPooo | £ -53,065 | |
| 12833 | oops | £ 965,477 | |
| 12834 | ooz | £ 320,966,832 | |
| 12835 | Opal Opal | £ 5,502,194 | |
| 12836 | Opec | £ 273,634,128 | |
| 12837 | Opel Dire | £ 5,505,993 | |
| 12838 | OpEn FoR BuIsNeSs | £ 5,785,269 | |
| 12839 | Opera House | £ 2,282,138 | |
| 12840 | Operation Racoon City | £ 4,748,173 | |
| 12841 | Operations | £ 8,189,228 | |
| 12842 | Ophthalmology | £ 45,575,639 | |
| 12843 | opiates | £ 10,578,986 | |
| 12844 | Opinion | £ 389,953,431 | |
| 12845 | OPiuM | £ 115,856,941 | |
| 12846 | Oppa Gangnam Style | £ 65,242,420 | |
| 12847 | Oppenheim | £ 51,959,450 | |
| 12848 | Oppertunity | £ 506,710,392 | |
| 12849 | Opportunity | £ 11,354,079 | |
| 12850 | Opposition | £ 761,831,311 | |
| 12851 | Oppression | £ 416,055,267 | |
| 12852 | optical | £ 449,516,871 | |
| 12853 | Optimal Flames | £ 168,931,399 | |
| 12854 | Optimum Nutrition | £ -3,018,246 | |
| 12855 | Optimus Inc. | £ -2,482,292 | |
| 12856 | Options | £ 84,494,650 | |
| 12857 | Opus Dei | £ 694,720,428 | |
| 12858 | opus technology | £ 35,372,824 | |
| 12859 | Oracle | £ 5,067,108 | |
| 12860 | Orakos | £ 5,484,841 | |
| 12861 | Orang | £ 36,992,851 | |
| 12862 | Orange | £ 24,725,264 | |
| 12863 | Orange Aftershock | £ 67,681,186 | |
| 12864 | Orange Castle | £ 615,362 | |
| 12865 | Orange Creatine | £ 6,196,167 | |
| 12866 | Orange Jelly | £ 6,594,926 | |
| 12867 | Orange Jooze | £ 1,261,621 | |
| 12868 | Orange Jooze 3 | £ 50,000 | |
| 12869 | Orange Jooze2 | £ 795,888 | |
| 12870 | Orange Jooze4 | £ 50,000 | |
| 12871 | Orange Jooze5 | £ 50,000 | |
| 12872 | Orange Juice | £ 38,460,358 | |
| 12873 | Orange Paint | £ 97,288,036 | |
| 12874 | Oranginal | £ 4,103,756 | |
| 12875 | oranje | £ 4,966,784 | |
| 12876 | Orbital | £ 54,539,946 | |
| 12877 | Orbital Bombardment | £ 1,188,671,445 | |
| 12878 | Orchids R Us Ltd | £ 39,331,588 | |
| 12879 | orcs | £ 2,521,634,731 | |
| 12880 | Orcustra | £ 702,800 | |
| 12881 | Order | £ 176,233,665 | |
| 12882 | Oregon | £ 111,775,168 | |
| 12883 | OREO | £ 64,657,012 | |
| 12884 | Org | £ 18,286,924 | |
| 12885 | Organic Beaver | £ 48,683,222 | |
| 12886 | Organics Ltd | £ 105,054,559 | |
| 12887 | Organised Crime | £ 17,216,443 | |
| 12888 | Organized Crime | £ 62,808,878 | |
| 12889 | Orgia Co. | £ 4,887,593 | |
| 12890 | Orgy | £ 4,311,652,261 | |
| 12891 | Origin yartley | £ 37,041,694 | |
| 12892 | Original 16 | £ 132,618,089 | |
| 12893 | Original Sin | £ 141,442,446 | |
| 12894 | Originality | £ 1,357,128,017 | |
| 12895 | Origins | £ 63,035,912 | |
| 12896 | Orino | £ 1,050,770 | |
| 12897 | Orion | £ 47,648,728 | |
| 12898 | orm | £ 413,783,803 | |
| 12899 | orming | £ 109,142,927 | |
| 12900 | OronzoMafia | £ 5,474,161 | |
