The following list shows all the companies that are in the game.
| Companies List | |||
| Pos. | Company Name | Awards | Total Worth |
| 12501 | Omni | £ 26,585,058 | |
| 12502 | Omni Consumer Products | £ -23,968,848 | |
| 12503 | omni4 | £ 1,185,151 | |
| 12504 | Omnia | £ 29,796,207 | |
| 12505 | on a stick | £ 13,410 | |
| 12506 | On all you Candyass | £ 69,045,286 | |
| 12507 | On Industries | £ 1,896,074 | |
| 12508 | On It | £ 59,533,659 | |
| 12509 | On My Mind | £ 87,748,385 | |
| 12510 | On The Fritz | £ 79,242,996 | |
| 12511 | on the road | £ 405,722,546 | |
| 12512 | Once Upon a Time | £ 24,760,937 | |
| 12513 | Once Were Warriors | £ 54,754,263 | |
| 12514 | one | £ 341,379,992 | |
| 12515 | One and a Half | £ 8,610,014,000 | |
| 12516 | One Company | £ 398,709,264 | |
| 12517 | one dollar company | £ 9,935,788 | |
| 12518 | One Eyed Three Leg Dog | £ 63,605,247 | |
| 12519 | One Hit Wonder | £ 30,087,678 | |
| 12520 | One Hundred Netro Bucks | £ 130,455,162 | |
| 12521 | One Insane Rastaman | £ 273,250,880 | |
| 12522 | one love | £ 3,838,898 | |
| 12523 | One Man | £ 3,996,240 | |
| 12524 | one man crying | £ 1,050,939,923 | |
| 12525 | One Mind | £ -5,139,455 | |
| 12526 | one of craze | £ 398,067,001 | |
| 12527 | One Piece | £ 11,282,781 | |
| 12528 | One Pound Fish | £ 1,584,921 | |
| 12529 | One Shot | £ 123,851,456 | |
| 12530 | One Silence | £ -4,074 | |
| 12531 | One to Many. | £ 4,976,234 | |
| 12532 | One United | £ 5,379,005 | |
| 12533 | one1 | £ 3,058,084 | |
| 12534 | OneNation | £ 45,456 | |
| 12535 | oneone | £ 18,206,569 | |
| 12536 | Oner | £ 10,516,756 | |
| 12537 | OneStopEnvelopeShoppe | £ -38,952 | |
| 12538 | Onion of Arabia | £ 11,458,256 | |
| 12539 | Onioninc | £ -43,613 | |
| 12540 | Onions | £ 56,031,337 | |
| 12541 | onions inc | £ 46,832,459 | |
| 12542 | ONLINE GAMES | £ 120,242,830 | |
| 12543 | Only Bombs Allowed | £ 57,741,277 | |
| 12544 | Only Fools and Horses | £ 859,719,219 | |
| 12545 | only me | £ 50,000 | |
| 12546 | only me inc | £ 133,078,068 | |
| 12547 | Onomatopoeias | £ 939,660 | |
| 12548 | Onshore Money | £ 104,918,400 | |
| 12549 | Ontara | £ 79,736,570 | |
| 12550 | Ontario | £ 85,260,376 | |
| 12551 | ontheblock | £ 6,402,837 | |
| 12552 | Onyx | £ 429,592 | |
| 12553 | OO7 | £ 55,808,206 | |
| 12554 | Ooglaigh na Heireann | £ 240,713,877 | |
| 12555 | oohyeaa | £ 50,844,745 | |
| 12556 | Oolacile-01 | £ 2,954,344 | |
| 12557 | oOoOo | £ 94,962,888 | |
| 12558 | oooooo | £ 5,505,528 | |
| 12559 | OOOoooOOO | £ 614,697 | |
| 12560 | oooPPPooo | £ -53,065 | |
| 12561 | oops | £ 965,477 | |
| 12562 | ooz | £ 320,966,832 | |
| 12563 | Opal Opal | £ 5,502,194 | |
| 12564 | Opec | £ 273,634,128 | |
| 12565 | Opel Dire | £ 5,505,993 | |
| 12566 | OpEn FoR BuIsNeSs | £ 5,785,269 | |
| 12567 | Operation Racoon City | £ 4,748,173 | |
| 12568 | Operations | £ 8,189,228 | |
| 12569 | Ophthalmology | £ 45,575,639 | |
| 12570 | opiates | £ 10,578,986 | |
| 12571 | Opinion | £ 389,953,431 | |
| 12572 | OPiuM | £ 115,856,941 | |
| 12573 | Oppa Gangnam Style | £ 65,242,420 | |
| 12574 | Oppenheim | £ 51,959,450 | |
| 12575 | Oppertunity | £ 458,210,505 | |
| 12576 | Opportunity | £ 11,354,079 | |
| 12577 | Opposition | £ 761,831,311 | |
| 12578 | Oppression | £ 416,055,267 | |
| 12579 | optical | £ 449,516,871 | |
| 12580 | Optimal Flames | £ 168,931,399 | |
| 12581 | Optimum Nutrition | £ -3,018,246 | |
| 12582 | Optimus Inc. | £ -2,482,292 | |
| 12583 | Options | £ 84,494,650 | |
| 12584 | Opus Dei | £ 694,720,428 | |
| 12585 | opus technology | £ 35,372,824 | |
| 12586 | Oracle | £ 5,067,108 | |
| 12587 | Orakos | £ 5,484,841 | |
| 12588 | Orange | £ 24,725,264 | |
| 12589 | Orange Aftershock | £ 67,681,186 | |
| 12590 | Orange Castle | £ 615,362 | |
| 12591 | Orange Creatine | £ 6,196,167 | |
| 12592 | Orange Jelly | £ 6,594,926 | |
| 12593 | Orange Jooze | £ 1,261,621 | |
| 12594 | Orange Jooze 3 | £ 50,000 | |
| 12595 | Orange Jooze2 | £ 795,888 | |
| 12596 | Orange Jooze4 | £ 50,000 | |
| 12597 | Orange Jooze5 | £ 50,000 | |
| 12598 | Orange Juice | £ 8,342,885 | |
| 12599 | Orange Paint | £ 97,288,036 | |
| 12600 | Oranginal | £ 4,103,756 | |
