The following list shows all the companies that are in the game.
| Companies List | |||
| Pos. | Company Name | Awards | Total Worth |
| 13101 | oooPPPooo | £ -53,065 | |
| 13102 | oops | £ 965,477 | |
| 13103 | ooz | £ 320,966,832 | |
| 13104 | Opal Opal | £ 5,502,194 | |
| 13105 | Opec | £ 273,634,128 | |
| 13106 | Opel Dire | £ 5,505,993 | |
| 13107 | OpEn FoR BuIsNeSs | £ 5,785,269 | |
| 13108 | Opera House | £ 12,830,242 | |
| 13109 | Operations | £ 8,189,228 | |
| 13110 | Ophthalmology | £ 45,575,639 | |
| 13111 | opiates | £ 10,578,986 | |
| 13112 | Opinion | £ 389,953,431 | |
| 13113 | OPiuM | £ 115,856,941 | |
| 13114 | Oppa Gangnam Style | £ 65,242,420 | |
| 13115 | Oppenheim | £ 51,959,450 | |
| 13116 | Oppertunity | £ 512,316,834 | |
| 13117 | Opportunity | £ 11,354,079 | |
| 13118 | Opposition | £ 761,831,311 | |
| 13119 | Oppression | £ 416,055,267 | |
| 13120 | optical | £ 449,516,871 | |
| 13121 | Optimal Flames | £ 168,931,399 | |
| 13122 | Optimum Nutrition | £ -3,018,246 | |
| 13123 | Optimus Inc. | £ -2,482,292 | |
| 13124 | Options | £ 84,494,650 | |
| 13125 | Opus Dei | £ 694,720,428 | |
| 13126 | opus technology | £ 35,372,824 | |
| 13127 | Oracle | £ 5,067,108 | |
| 13128 | Orakos | £ 5,484,841 | |
| 13129 | Orang | £ 46,959,797 | |
| 13130 | Orange | £ 24,725,264 | |
| 13131 | Orange Aftershock | £ 67,681,186 | |
| 13132 | Orange Castle | £ 615,362 | |
| 13133 | Orange Creatine | £ 6,196,167 | |
| 13134 | Orange Jelly | £ 6,594,926 | |
| 13135 | Orange Jooze | £ 1,261,621 | |
| 13136 | Orange Jooze 3 | £ 50,000 | |
| 13137 | Orange Jooze2 | £ 795,888 | |
| 13138 | Orange Jooze4 | £ 50,000 | |
| 13139 | Orange Jooze5 | £ 50,000 | |
| 13140 | Orange Juice | £ 115,127,546 | |
| 13141 | Orange Paint | £ 97,288,036 | |
| 13142 | Oranginal | £ 4,103,756 | |
| 13143 | oranje | £ 4,966,784 | |
| 13144 | Orbital | £ 54,539,946 | |
| 13145 | Orbital Bombardment | £ 1,188,671,445 | |
| 13146 | Orbital Mechanics | £ 31,506,406 | |
| 13147 | Orchids R Us Ltd | £ 39,331,588 | |
| 13148 | orcs | £ 2,521,634,731 | |
| 13149 | Orcustra | £ 702,800 | |
| 13150 | Order | £ 176,233,665 | |
| 13151 | ordinary matter | £ 104,375,481 | |
| 13152 | Oregon | £ 111,775,168 | |
| 13153 | OREO | £ 64,657,012 | |
| 13154 | Org | £ 18,286,924 | |
| 13155 | Organic Beaver | £ 48,683,222 | |
| 13156 | Organics Ltd | £ 105,054,559 | |
| 13157 | Organised Crime | £ 17,216,443 | |
| 13158 | Organized Crime | £ 62,808,878 | |
| 13159 | Orgia Co. | £ 4,887,593 | |
| 13160 | Orgy | £ 4,311,652,261 | |
| 13161 | Origin yartley | £ 37,041,694 | |
| 13162 | Original 16 | £ 132,618,089 | |
| 13163 | Original Sin | £ 141,442,446 | |
| 13164 | Originality | £ 1,357,128,017 | |
| 13165 | Origins | £ 63,035,912 | |
| 13166 | Orino | £ 56,346,103 | |
| 13167 | Orion | £ 47,648,728 | |
| 13168 | orm | £ 413,783,803 | |
| 13169 | orming | £ 109,142,927 | |
| 13170 | OronzoMafia | £ 5,474,161 | |
| 13171 | Orphans Court | £ 288,318,982 | |
| 13172 | Orphic Co. | £ 4,423,125 | |
| 13173 | Orquinox Co. | £ 1,119 | |
| 13174 | Orricks IT Services | £ 15,082,611 | |
| 13175 | Ortcaj | £ 77,296,813 | |
| 13176 | Orthanc Inc. | £ 147,448,563 | |
| 13177 | Osaka | £ 5,504,057 | |
| 13178 | Osakin | £ 6,161,131 | |
| 13179 | osca-websites | £ 9,181,996 | |
| 13180 | Oscar Meyer | £ 5,773,809 | |
| 13181 | Oscorp Industries | £ 179,374 | |
| 13182 | OSHA Six Flags | £ 5,346,082 | |
| 13183 | Osho | £ 4,055,871 | |
| 13184 | Osipolis | £ 16,660,041 | |
| 13185 | Osiris | £ 225,126,101 | |
| 13186 | osiris666 | £ -1,880,407 | |
| 13187 | osiris6971 | £ 10,377,105 | |
| 13188 | Osmosis | £ 36,967,752 | |
| 13189 | Osprey Close | £ 53,590,765 | |
| 13190 | other comps | £ 277,474,569 | |
| 13191 | Other Reality | £ 4,518,202 | |
| 13192 | Otherones | £ 61,853,286 | |
| 13193 | Others | £ 26,039,960 | |
| 13194 | otherwil | £ 133,717 | |
| 13195 | otherwil2 | £ -34,567,223 | |
| 13196 | otherwil3 | £ 1,893,225 | |
| 13197 | otherwil4 | £ 4,826,025 | |
| 13198 | otherwil5 | £ 829,030 | |
| 13199 | Ottawa | £ 44,778,874 | |
| 13200 | Otto | £ 511,521,836 | |
