The following list shows all the companies that are in the game.
| Companies List | |||
| Pos. | Company Name | Awards | Total Worth |
| 13301 | Once Upon a Time | £ 24,760,937 | |
| 13302 | Once Were Warriors | £ 54,754,263 | |
| 13303 | one | £ 341,379,992 | |
| 13304 | One and a Half | £ 8,610,014,000 | |
| 13305 | One Company | £ 398,709,264 | |
| 13306 | one dollar company | £ 40,885,349 | |
| 13307 | One Eyed Three Leg Dog | £ 63,605,247 | |
| 13308 | One gun | £ 170,204,825 | |
| 13309 | One Hit Wonder | £ 30,087,678 | |
| 13310 | One Hundred Netro Bucks | £ 130,455,162 | |
| 13311 | One Insane Rastaman | £ 273,250,880 | |
| 13312 | one love | £ 3,838,898 | |
| 13313 | One Man | £ 3,996,240 | |
| 13314 | one man crying | £ 1,050,939,923 | |
| 13315 | One Mind | £ -5,139,455 | |
| 13316 | one of craze | £ 398,067,001 | |
| 13317 | One Piece | £ 11,282,781 | |
| 13318 | One Pound Fish | £ 1,584,921 | |
| 13319 | One Shot | £ 123,851,456 | |
| 13320 | One Silence | £ -4,074 | |
| 13321 | One to Many. | £ 4,976,234 | |
| 13322 | One Two Many | £ 43,542,088 | |
| 13323 | One United | £ 5,379,005 | |
| 13324 | one1 | £ 1,933,505 | |
| 13325 | OneNation | £ 45,456 | |
| 13326 | oneone | £ 18,206,569 | |
| 13327 | Oner | £ 10,516,756 | |
| 13328 | OneStopEnvelopeShoppe | £ -38,952 | |
| 13329 | Onion of Arabia | £ 11,458,256 | |
| 13330 | Onioninc | £ -43,613 | |
| 13331 | Onions | £ 56,031,337 | |
| 13332 | onions inc | £ 46,832,459 | |
| 13333 | ONLINE GAMES | £ 120,242,830 | |
| 13334 | Only Bombs Allowed | £ 57,741,277 | |
| 13335 | Only Fans | £ 115,885,097 | |
| 13336 | Only Fools and Horses | £ 859,719,219 | |
| 13337 | only me | £ 50,000 | |
| 13338 | only me inc | £ 133,078,068 | |
| 13339 | Onomatopoeias | £ 939,660 | |
| 13340 | Onshore Money | £ 104,918,400 | |
| 13341 | Ontara | £ 79,736,570 | |
| 13342 | Ontario | £ 85,260,376 | |
| 13343 | ontheblock | £ 6,402,837 | |
| 13344 | Onyx | £ 429,592 | |
| 13345 | OO7 | £ 55,808,206 | |
| 13346 | Ooglaigh na Heireann | £ 240,713,877 | |
| 13347 | oohyeaa | £ 50,844,745 | |
| 13348 | Oolacile-01 | £ 3,643,194 | |
| 13349 | oOoOo | £ 248,934,291 | |
| 13350 | oooooo | £ 5,505,528 | |
| 13351 | OOOoooOOO | £ 614,697 | |
| 13352 | oooPPPooo | £ -53,065 | |
| 13353 | oops | £ 965,477 | |
| 13354 | ooz | £ 320,966,832 | |
| 13355 | Opal Opal | £ 5,502,194 | |
| 13356 | Opec | £ 273,634,128 | |
| 13357 | Opel Dire | £ 5,505,993 | |
| 13358 | OpEn FoR BuIsNeSs | £ 5,785,269 | |
| 13359 | Opera House | £ 14,521,545 | |
| 13360 | Operations | £ 8,189,228 | |
| 13361 | Ophthalmology | £ 45,575,639 | |
| 13362 | opiates | £ 10,578,986 | |
| 13363 | Opinion | £ 389,953,431 | |
| 13364 | OPiuM | £ 115,856,941 | |
| 13365 | Oppa Gangnam Style | £ 65,242,420 | |
| 13366 | Oppenheim | £ 51,959,450 | |
| 13367 | Oppertunity | £ 512,316,834 | |
| 13368 | Opportunity | £ 11,354,079 | |
| 13369 | Opposition | £ 761,831,311 | |
| 13370 | Oppression | £ 416,055,267 | |
| 13371 | optical | £ 449,516,871 | |
| 13372 | Optimal Flames | £ 171,588,986 | |
| 13373 | Optimum Nutrition | £ -3,018,246 | |
| 13374 | Optimus Inc. | £ -2,482,292 | |
| 13375 | Options | £ 84,494,650 | |
| 13376 | Opus Dei | £ 694,720,428 | |
| 13377 | opus technology | £ 35,372,824 | |
| 13378 | Oracle | £ 5,067,108 | |
| 13379 | Orakos | £ 5,484,841 | |
| 13380 | Orang | £ 46,959,797 | |
| 13381 | Orange | £ 24,725,264 | |
| 13382 | Orange Aftershock | £ 67,681,186 | |
| 13383 | Orange Castle | £ 615,362 | |
| 13384 | Orange Creatine | £ 6,196,167 | |
| 13385 | Orange Jelly | £ 6,594,926 | |
| 13386 | Orange Jooze | £ 1,261,621 | |
| 13387 | Orange Jooze 3 | £ 50,000 | |
| 13388 | Orange Jooze2 | £ 795,888 | |
| 13389 | Orange Jooze4 | £ 50,000 | |
| 13390 | Orange Jooze5 | £ 50,000 | |
| 13391 | Orange Juice | £ 123,922,208 | |
| 13392 | Orange Paint | £ 97,288,036 | |
| 13393 | Oranginal | £ 4,103,756 | |
| 13394 | oranje | £ 4,966,784 | |
| 13395 | Orbital | £ 54,539,946 | |
| 13396 | Orbital Bombardment | £ 1,188,671,445 | |
| 13397 | Orbital Mechanics | £ 43,564,501 | |
| 13398 | Orchids R Us Ltd | £ 39,331,588 | |
| 13399 | orcs | £ 2,521,634,731 | |
| 13400 | Orcustra | £ 702,800 | |
