The following list shows all the companies that are in the game.
| Companies List | |||
| Pos. | Company Name | Awards | Total Worth |
| 12401 | Oil CONGLOMO | £ 2,646,845 | |
| 12402 | Oil Field | £ 271,568 | |
| 12403 | Oil Inc | £ 1,596,655 | |
| 12404 | Oil Industry | £ 4,441,721 | |
| 12405 | Oil Rigger | £ 2,151,587,047 | |
| 12406 | Oilfield Industries | £ 9,854,297 | |
| 12407 | oiu | £ 5,498,037 | |
| 12408 | OJ da Juiceman | £ 109,855 | |
| 12409 | OK Tom | £ 193,936,455 | |
| 12410 | OKFurniture | £ 50,000 | |
| 12411 | OKG Shed | £ -329,334 | |
| 12412 | OKS 1 PTE LTD | £ 50,000 | |
| 12413 | OKS PTE LTD | £ 2,148,676 | |
| 12414 | OLafa | £ 5,088,982 | |
| 12415 | Oland Ltd | £ 50,000 | |
| 12416 | Olay | £ 290,473,960 | |
| 12417 | Old Age | £ 372,141,647 | |
| 12418 | Old Bay | £ 123,534,579 | |
| 12419 | Old Bill | £ 45,792,842 | |
| 12420 | Old Carpet | £ 163,972,008 | |
| 12421 | old farts | £ 3,542,428,093 | |
| 12422 | Old Feuds | £ 44,696,704 | |
| 12423 | Old Granny | £ 9,329,769 | |
| 12424 | old lard | £ -7,521,344 | |
| 12425 | old legends | £ 14,735,844 | |
| 12426 | Old men | £ 397,899,239 | |
| 12427 | Old No. 7 | £ 620,700,257 | |
| 12428 | Old people | £ 41,298,004 | |
| 12429 | Old Rocker | £ 305,100,308 | |
| 12430 | Old School | £ 5,514,041 | |
| 12431 | old skool butta | £ 614,087 | |
| 12432 | Old Smoky | £ 622,122,584 | |
| 12433 | Old Socks | £ 144,379,758 | |
| 12434 | Old Whiskey | £ 17,558,590 | |
| 12435 | Old World Industry | £ 1,734,908 | |
| 12436 | Old World Ventures | £ 50,000 | |
| 12437 | OlDirty | £ 47,991,916 | |
| 12438 | oldschool | £ 87,915,709 | |
| 12439 | Oligarchy | £ 556,860,397 | |
| 12440 | Oligarchy inc. | £ 7,116,723 | |
| 12441 | olis | £ 91,036,818 | |
| 12442 | Oliver Cromwell | £ 220,112,740 | |
| 12443 | Oliver Queen | £ 56,107,912 | |
| 12444 | Olivers Imagination | £ 124,320,555 | |
| 12445 | Olrik | £ 22,147,425 | |
| 12446 | Olympia | £ 112,782,553 | |
| 12447 | olympic rings | £ 3,079,579,731 | |
| 12448 | Olympics | £ 5,508,747 | |
| 12449 | Olympus | £ 2,062,876,669 | |
| 12450 | Omega | £ 6,183,955 | |
| 12451 | Omega Indusries | £ 37,799 | |
| 12452 | OmegaFox Inc. | £ 1,266,634 | |
| 12453 | Omelette | £ 10,061,528 | |
| 12454 | Omerta | £ 1,007,186,123 | |
| 12455 | Omerta Inc. | £ 5,500,096 | |
| 12456 | Omni | £ 26,585,058 | |
| 12457 | Omni Consumer Products | £ -23,968,848 | |
| 12458 | omni4 | £ 1,185,151 | |
| 12459 | Omnia | £ 29,796,207 | |
| 12460 | on a stick | £ 13,410 | |
| 12461 | On all you Candyass | £ 69,045,286 | |
| 12462 | On Industries | £ 1,896,074 | |
| 12463 | On It | £ 59,533,659 | |
| 12464 | On My Mind | £ 87,748,385 | |
| 12465 | On The Fritz | £ 79,242,996 | |
| 12466 | on the road | £ 405,722,546 | |
| 12467 | Once Upon a Time | £ 24,760,937 | |
| 12468 | Once Were Warriors | £ 54,754,263 | |
| 12469 | one | £ 341,379,992 | |
| 12470 | One and a Half | £ 8,610,014,000 | |
| 12471 | One Company | £ 398,709,264 | |
| 12472 | One Eyed Three Leg Dog | £ 63,605,247 | |
| 12473 | One Hit Wonder | £ 30,087,678 | |
| 12474 | One Hundred Netro Bucks | £ 130,455,162 | |
| 12475 | One Insane Rastaman | £ 273,250,880 | |
| 12476 | one love | £ 3,838,898 | |
| 12477 | One Man | £ 3,996,240 | |
| 12478 | one man crying | £ 1,057,960,641 | |
| 12479 | One Mind | £ -5,139,455 | |
| 12480 | one of craze | £ 398,067,001 | |
| 12481 | One Piece | £ 11,282,781 | |
| 12482 | One Pound Fish | £ 1,584,921 | |
| 12483 | One Shot | £ 123,851,456 | |
| 12484 | One Silence | £ -4,074 | |
| 12485 | One to Many. | £ 4,976,234 | |
| 12486 | One United | £ 5,379,005 | |
| 12487 | one1 | £ 3,058,084 | |
| 12488 | OneNation | £ 45,456 | |
| 12489 | oneone | £ 18,206,569 | |
| 12490 | Oner | £ 10,516,756 | |
| 12491 | OneStopEnvelopeShoppe | £ -38,952 | |
| 12492 | Onion of Arabia | £ 11,458,256 | |
| 12493 | Onions | £ 56,031,337 | |
| 12494 | onions inc | £ 46,832,459 | |
| 12495 | ONLINE GAMES | £ 120,242,830 | |
| 12496 | Only Bombs Allowed | £ 57,741,277 | |
| 12497 | Only Fools and Horses | £ 859,719,219 | |
| 12498 | only me | £ 50,000 | |
| 12499 | only me inc | £ 133,078,068 | |
| 12500 | Onomatopoeias | £ 939,660 | |
