The following list shows all the companies that are in the game.
| Companies List | |||
| Pos. | Company Name | Awards | Total Worth |
| 16601 | operating systems | £ 44,182,451 | |
| 16602 | Operation Centerboard | £ 45,661,943 | |
| 16603 | OPERATION SEALION | £ 10,353,786 | |
| 16604 | OPERATION SEALION 2 | £ 5,504,218 | |
| 16605 | Ophthalmology | £ 45,575,639 | |
| 16606 | Opinion | £ 389,953,431 | |
| 16607 | OPiuM | £ 115,856,941 | |
| 16608 | Oppa Gangnam Style | £ 65,242,420 | |
| 16609 | Oppenheim | £ 51,959,450 | |
| 16610 | Oppenheimer | £ 1,424,302 | |
| 16611 | Oppertunity | £ 512,316,834 | |
| 16612 | Opportunities | £ 58,183,350 | |
| 16613 | Opportunity | £ 11,354,079 | |
| 16614 | Opposition | £ 761,831,311 | |
| 16615 | Oppression | £ 416,055,267 | |
| 16616 | OpRedStripe | £ 39,676,062 | |
| 16617 | optics | £ 57,286,889 | |
| 16618 | Optimal Flames | £ 175,592,178 | |
| 16619 | Optimum Nutrition | £ -3,018,246 | |
| 16620 | Optimus Inc. | £ -2,482,292 | |
| 16621 | Options | £ 84,494,650 | |
| 16622 | Options Trading | £ 15,395,474 | |
| 16623 | Opus Dei | £ 1,685,731,893 | |
| 16624 | opus technology | £ 35,372,824 | |
| 16625 | Or Fords | £ 45,353,900 | |
| 16626 | Oracle | £ 5,067,108 | |
| 16627 | Orakos | £ 9,653,572 | |
| 16628 | Orange | £ 24,725,264 | |
| 16629 | Orange Aftershock | £ 67,681,186 | |
| 16630 | Orange Castle | £ 615,362 | |
| 16631 | Orange County | £ 4,910,507 | |
| 16632 | Orange Creatine | £ 6,196,167 | |
| 16633 | Orange Jelly | £ 6,594,926 | |
| 16634 | Orange Jooze | £ 1,261,621 | |
| 16635 | Orange Jooze 3 | £ 50,000 | |
| 16636 | Orange Jooze2 | £ 795,888 | |
| 16637 | Orange Jooze4 | £ 50,000 | |
| 16638 | Orange Jooze5 | £ 50,000 | |
| 16639 | Orange Mango | £ 9,110,398 | |
| 16640 | Orange Paint | £ 97,288,036 | |
| 16641 | Oranginal | £ 4,103,756 | |
| 16642 | oranje | £ 4,966,784 | |
| 16643 | Orbital | £ 54,539,946 | |
| 16644 | Orbital Bombardment | £ 1,279,471,445 | |
| 16645 | Orbital Mechanics | £ 180,218,458 | |
| 16646 | Orbital Oasis | £ 61,220,273 | |
| 16647 | Orchids R Us Ltd | £ 39,331,588 | |
| 16648 | orcs | £ 2,521,634,731 | |
| 16649 | Orcustra | £ 702,800 | |
| 16650 | Order | £ 176,233,665 | |
| 16651 | Order Flow | £ 121,681,973 | |
| 16652 | Orders | £ 27,738,927 | |
| 16653 | Ordinance | £ 12,412,156 | |
| 16654 | ordinary matter | £ 329,649,091 | |
| 16655 | Oregon | £ 111,775,168 | |
| 16656 | OREO | £ 64,657,012 | |
| 16657 | Org | £ 18,286,924 | |
| 16658 | Organic Fruits and Veggy | £ 23,175,728 | |
| 16659 | Organics Ltd | £ 105,054,559 | |
| 16660 | Organised | £ 15,782,169 | |
| 16661 | Organised Crime | £ 17,216,443 | |
| 16662 | Organised.net | £ 55,489,672 | |
| 16663 | Organized Crime | £ 62,808,878 | |
| 16664 | Orgia Co. | £ 4,887,593 | |
| 16665 | Orgy | £ 6,092,194,361 | |
| 16666 | Origin | £ 1,770,084,404 | |
| 16667 | Origin yartley | £ 37,041,694 | |
| 16668 | Original 16 | £ 174,342,608 | |
| 16669 | Original Gangster | £ 57,314,245 | |
| 16670 | Original Sin | £ 144,878,801 | |
| 16671 | Original Taste | £ 47,942,688 | |
| 16672 | Original Thoughts | £ 156,058,221 | |
| 16673 | Originality | £ 2,404,207,968 | |
| 16674 | Origins | £ 63,035,912 | |
| 16675 | Orino | £ 56,346,103 | |
| 16676 | Orion | £ 47,648,728 | |
| 16677 | Orion. | £ 374,172,630 | |
| 16678 | Orleans | £ 56,160,211 | |
| 16679 | orm | £ 2,684,322,281 | |
| 16680 | orming | £ 84,475,985 | |
| 16681 | Ornamental Knights | £ 3,129,157 | |
| 16682 | Ornate | £ -8,047,867 | |
| 16683 | Orome Aldaron | £ 1,531,184,473 | |
| 16684 | OronzoMafia | £ 5,474,161 | |
| 16685 | Orphans Court | £ 297,981,744 | |
| 16686 | Orpheus | £ 288,236,792 | |
| 16687 | Orphic Co. | £ 4,423,125 | |
| 16688 | Orquinox Co. | £ 1,119 | |
| 16689 | Orricks IT Services | £ 15,082,611 | |
| 16690 | Ortcaj | £ 77,296,813 | |
| 16691 | Orthanc Inc. | £ 147,448,563 | |
| 16692 | Osaka | £ 5,504,057 | |
| 16693 | Osakin | £ 6,161,131 | |
| 16694 | Osbourne | £ 1,744,973 | |
| 16695 | osca-websites | £ 9,181,996 | |
| 16696 | Oscar Meyer | £ 5,773,809 | |
| 16697 | Oscars Emporium | £ 148,690,217 | |
| 16698 | Oscillation | £ 3,001,978 | |
| 16699 | Oscorp Industries | £ 179,374 | |
| 16700 | OSHA Six Flags | £ 5,346,082 | |
