The following list shows all the companies that are in the game.
| Companies List | |||
| Pos. | Company Name | Awards | Total Worth |
| 12201 | on a stick | £ 13,410 | |
| 12202 | On all you Candyass | £ 69,045,286 | |
| 12203 | On Industries | £ 1,896,074 | |
| 12204 | On It | £ 59,533,659 | |
| 12205 | On My Mind | £ 87,748,385 | |
| 12206 | On The Fritz | £ 79,242,996 | |
| 12207 | on the road | £ 57,677,607 | |
| 12208 | Once Upon a Time | £ 24,760,937 | |
| 12209 | Once Were Warriors | £ 54,754,263 | |
| 12210 | one | £ 341,379,992 | |
| 12211 | One and a Half | £ 8,610,014,000 | |
| 12212 | One Company | £ 398,709,264 | |
| 12213 | One Eyed Three Leg Dog | £ 63,605,247 | |
| 12214 | One Hit Wonder | £ 30,087,678 | |
| 12215 | One Hundred Netro Bucks | £ 111,634,799 | |
| 12216 | One Insane Rastaman | £ 270,055,477 | |
| 12217 | one love | £ 3,838,898 | |
| 12218 | one man crying | £ 1,034,568,851 | |
| 12219 | One Mind | £ -5,139,455 | |
| 12220 | one of craze | £ 398,067,001 | |
| 12221 | One Piece | £ 11,282,781 | |
| 12222 | One Pound Fish | £ 1,584,921 | |
| 12223 | One Shot | £ 123,851,456 | |
| 12224 | One Silence | £ -4,074 | |
| 12225 | One to Many. | £ 4,976,234 | |
| 12226 | One United | £ 5,379,005 | |
| 12227 | one1 | £ 3,058,084 | |
| 12228 | OneNation | £ 45,456 | |
| 12229 | oneone | £ 18,206,569 | |
| 12230 | Oner | £ 10,516,756 | |
| 12231 | OneStopEnvelopeShoppe | £ -38,952 | |
| 12232 | Onion of Arabia | £ 11,458,256 | |
| 12233 | Onions | £ 56,031,337 | |
| 12234 | onions inc | £ 46,832,459 | |
| 12235 | ONLINE GAMES | £ 120,242,830 | |
| 12236 | Only Bombs Allowed | £ 57,741,277 | |
| 12237 | Only Fools and Horses | £ 859,719,219 | |
| 12238 | only me | £ 50,000 | |
| 12239 | only me inc | £ 133,078,068 | |
| 12240 | Onomatopoeias | £ 939,660 | |
| 12241 | Onshore Money | £ 104,918,400 | |
| 12242 | Ontara | £ 79,736,570 | |
| 12243 | Ontario | £ 85,260,376 | |
| 12244 | ontheblock | £ 6,402,837 | |
| 12245 | Onyx | £ 429,592 | |
| 12246 | OO7 | £ 5,508,861 | |
| 12247 | Ooglaigh na Heireann | £ 240,713,877 | |
| 12248 | oohyeaa | £ 50,844,745 | |
| 12249 | Oolacile-01 | £ 2,954,344 | |
| 12250 | oOoOo | £ 31,474,744 | |
| 12251 | oooooo | £ 5,505,528 | |
| 12252 | OOOoooOOO | £ 614,697 | |
| 12253 | oooPPPooo | £ -53,065 | |
| 12254 | oops | £ 965,477 | |
| 12255 | ooz | £ 320,966,832 | |
| 12256 | Opal Opal | £ 5,502,194 | |
| 12257 | Opec | £ 273,634,128 | |
| 12258 | Opel Dire | £ 5,505,993 | |
| 12259 | OpEn FoR BuIsNeSs | £ 5,785,269 | |
| 12260 | Operation Racoon City | £ 4,748,173 | |
| 12261 | Operations | £ 8,189,228 | |
| 12262 | Ophthalmology | £ 45,575,639 | |
| 12263 | opiates | £ 10,578,986 | |
| 12264 | Opinion | £ 389,953,431 | |
| 12265 | OPiuM | £ 115,856,941 | |
| 12266 | Oppa Gangnam Style | £ 65,242,420 | |
| 12267 | Oppenheim | £ 51,959,450 | |
| 12268 | Oppertunity | £ 458,210,505 | |
| 12269 | Opportunity | £ 11,354,079 | |
| 12270 | Opposition | £ 761,831,311 | |
| 12271 | Oppression | £ 416,055,267 | |
| 12272 | optical | £ 370,388,157 | |
| 12273 | Optimal Flames | £ 168,931,399 | |
| 12274 | Optimum Nutrition | £ -3,018,246 | |
| 12275 | Optimus Inc. | £ -2,482,292 | |
| 12276 | Options | £ 84,494,650 | |
| 12277 | Opus Dei | £ 694,720,428 | |
| 12278 | opus technology | £ 35,372,824 | |
| 12279 | Oracle | £ 5,067,108 | |
| 12280 | Orange | £ 24,725,264 | |
| 12281 | Orange Aftershock | £ 67,681,186 | |
| 12282 | Orange Castle | £ 615,362 | |
| 12283 | Orange Creatine | £ 6,196,167 | |
| 12284 | Orange Jelly | £ 6,594,926 | |
| 12285 | Orange Jooze | £ 1,261,621 | |
| 12286 | Orange Jooze 3 | £ 50,000 | |
| 12287 | Orange Jooze2 | £ 795,888 | |
| 12288 | Orange Jooze4 | £ 50,000 | |
| 12289 | Orange Jooze5 | £ 50,000 | |
| 12290 | Orange Paint | £ 97,288,036 | |
| 12291 | Oranginal | £ 4,103,756 | |
| 12292 | oranje | £ 4,966,784 | |
| 12293 | Orbital | £ 54,539,946 | |
| 12294 | Orbital Bombardment | £ 506,820,637 | |
| 12295 | Orchids R Us Ltd | £ 39,331,588 | |
| 12296 | orcs | £ 2,466,557,543 | |
| 12297 | Orcustra | £ 702,800 | |
| 12298 | Order | £ 176,233,665 | |
| 12299 | Oregon | £ 111,775,168 | |
| 12300 | OREO | £ 64,657,012 | |
