The following list shows all the companies that are in the game.
| Companies List | |||
| Pos. | Company Name | Awards | Total Worth |
| 12001 | Omni Consumer Products | £ -6,251,555 | |
| 12002 | omni4 | £ 1,185,151 | |
| 12003 | Omnia | £ 29,796,207 | |
| 12004 | on a stick | £ 13,410 | |
| 12005 | On all you Candyass | £ 69,045,286 | |
| 12006 | On Industries | £ 1,896,074 | |
| 12007 | On It | £ 59,533,659 | |
| 12008 | On My Mind | £ 87,748,385 | |
| 12009 | On The Fritz | £ 79,242,996 | |
| 12010 | on the road | £ 54,975,023 | |
| 12011 | Once Upon a Time | £ 24,760,937 | |
| 12012 | Once Were Warriors | £ 54,754,263 | |
| 12013 | one | £ 341,379,992 | |
| 12014 | One and a Half | £ 8,567,091,666 | |
| 12015 | One Company | £ 398,709,264 | |
| 12016 | One Eyed Three Leg Dog | £ 63,605,247 | |
| 12017 | One Hit Wonder | £ 30,087,678 | |
| 12018 | One Hundred Netro Bucks | £ 46,596,172 | |
| 12019 | One Insane Rastaman | £ 245,274,978 | |
| 12020 | one love | £ 3,838,898 | |
| 12021 | one man crying | £ 956,203,378 | |
| 12022 | One Mind | £ -5,139,455 | |
| 12023 | one of craze | £ 398,067,001 | |
| 12024 | One Piece | £ 11,282,781 | |
| 12025 | One Pound Fish | £ 1,584,921 | |
| 12026 | One Shot | £ 123,851,456 | |
| 12027 | One Silence | £ -4,074 | |
| 12028 | One to Many. | £ 4,976,234 | |
| 12029 | One United | £ 5,379,005 | |
| 12030 | one1 | £ 3,058,084 | |
| 12031 | OneNation | £ 45,456 | |
| 12032 | oneone | £ 18,206,569 | |
| 12033 | Oner | £ 10,516,756 | |
| 12034 | OneStopEnvelopeShoppe | £ -38,952 | |
| 12035 | Onion of Arabia | £ 11,458,256 | |
| 12036 | Onions | £ 56,031,337 | |
| 12037 | onions inc | £ 46,832,459 | |
| 12038 | ONLINE GAMES | £ 120,242,830 | |
| 12039 | Only Bombs Allowed | £ 57,741,277 | |
| 12040 | Only Fools and Horses | £ 700,613,498 | |
| 12041 | only me | £ 50,000 | |
| 12042 | only me inc | £ 133,078,068 | |
| 12043 | Onomatopoeias | £ 939,660 | |
| 12044 | Onshore Money | £ 104,918,400 | |
| 12045 | Ontara | £ 79,736,570 | |
| 12046 | Ontario | £ 85,260,376 | |
| 12047 | ontheblock | £ 6,402,837 | |
| 12048 | Onyx | £ 429,592 | |
| 12049 | OO7 | £ 5,508,861 | |
| 12050 | Ooglaigh na Heireann | £ 240,713,877 | |
| 12051 | oohyeaa | £ 50,844,745 | |
| 12052 | Oolacile-01 | £ 2,954,344 | |
| 12053 | oOoOo | £ 35,513,896 | |
| 12054 | oooooo | £ 5,505,528 | |
| 12055 | OOOoooOOO | £ 614,697 | |
| 12056 | oooPPPooo | £ -53,065 | |
| 12057 | oops | £ 965,477 | |
| 12058 | ooz | £ 320,966,832 | |
| 12059 | Opal Opal | £ 5,502,194 | |
| 12060 | Opec | £ 159,504,964 | |
| 12061 | Opel Dire | £ 5,505,993 | |
| 12062 | OpEn FoR BuIsNeSs | £ 5,785,269 | |
| 12063 | Operation Racoon City | £ 4,748,173 | |
| 12064 | Operations | £ 8,189,228 | |
| 12065 | Ophthalmology | £ 45,575,639 | |
| 12066 | opiates | £ 10,578,986 | |
| 12067 | Opinion | £ 389,953,431 | |
| 12068 | OPiuM | £ 115,856,941 | |
| 12069 | Oppa Gangnam Style | £ 65,242,420 | |
| 12070 | Oppenheim | £ 51,959,450 | |
| 12071 | Oppertunity | £ 458,210,505 | |
| 12072 | Opportunity | £ 11,354,079 | |
| 12073 | Opposition | £ 761,831,311 | |
| 12074 | Oppression | £ 416,055,267 | |
| 12075 | optical | £ 244,092,617 | |
| 12076 | Optimal Flames | £ 168,931,399 | |
| 12077 | Optimum Nutrition | £ -3,018,246 | |
| 12078 | Optimus Inc. | £ -2,482,292 | |
| 12079 | Options | £ 84,494,650 | |
| 12080 | Opus Dei | £ 694,720,428 | |
| 12081 | opus technology | £ 35,372,824 | |
| 12082 | Oracle | £ 5,067,108 | |
| 12083 | Orange | £ 24,725,264 | |
| 12084 | Orange Aftershock | £ 67,681,186 | |
| 12085 | Orange Castle | £ 615,362 | |
| 12086 | Orange Creatine | £ 6,196,167 | |
| 12087 | Orange Jelly | £ 6,594,926 | |
| 12088 | Orange Jooze | £ 1,261,621 | |
| 12089 | Orange Jooze 3 | £ 50,000 | |
| 12090 | Orange Jooze2 | £ 795,888 | |
| 12091 | Orange Jooze4 | £ 50,000 | |
| 12092 | Orange Jooze5 | £ 50,000 | |
| 12093 | Orange Paint | £ 97,288,036 | |
| 12094 | Oranginal | £ 4,103,756 | |
| 12095 | oranje | £ 4,966,784 | |
| 12096 | Orbital | £ 54,539,946 | |
| 12097 | Orbital Bombardment | £ 329,853,903 | |
| 12098 | Orchids R Us Ltd | £ 39,331,588 | |
| 12099 | orcs | £ 2,377,116,516 | |
| 12100 | Orcustra | £ 702,800 | |
