A multiple system operator or multi system operator (MSO) is an operator of multiple cable television systems. A cable system in the United States, by Federal Communications Commission (FCC) definition, is a facility serving a single community or a distinct governmental entity, each with its own franchise agreement with the cable company. Though in the strictest sense any cable company that serves multiple communities is thus an MSO, the term today is usually reserved for companies that own a very large number of cable systems, such as Time Warner Cable, Cablevision, Comcast, Charter Communications and Cox Communications in the US, Rogers Communications, Videotron and Shaw Communications in Canada or Virgin Media in the UK.
Top MSOs Worldwide by Number of Subscribers:
| Rank | Country | MSO Name | # of Subscribers |
| 1 | USA | Comcast Corporation |
24,182,000 |
| 2 | USA | Time Warner Cable |
12,859,000 |
| 3 | EMEA | UPC Broadband (9 in Europe)[1] |
9,100,000 |
| 4 | Germany | Kabel Deutschland[2] |
8,900,000 |
| 5 | USA | Cox Communication |
5,195,000 |
| 6 | USA | Charter Communications |
4,824,000 |
| 7 | UK | Virgin Media |
4,772,800 |
| 8 | France | Numericable[3] |
3,500,000 |
| 9 | Japan | J:Com |
3,300,000 |
| 10 | USA | Cablevision Systems Corporation |
3,063,000 |
| 11 | Belgum | Telenet |
2,300,000 |
| 12 | Germany | Kabel BW |
2,300,000 |
| 13 | Canada | Rogers |
2,295,000 |
| 14 | USA | Bright House Networks |
2,264,000 |
| 15 | Canada | Shaw |
2,241,503 |
| 16 | Spain | ONO[4] |
1,823,536 |
| 17 | Sweden | Com Hem |
1,760,000 |
| 18 | China | Cablecom |
1,670,000 |
| 19 | Canada | Videotron |
1,652,200 |
| 20 | Netherlands | Ziggo[5] |
1,600,000 |
| 21 | China | Jinan Cable Network |
1,300,000 |
| 22 | USA | Suddenlink Communications |
1,239,000 |
| 23 | USA | Mediacom Communications Corporation |
1,238,000 |
| 24 | Canada | Star Choice |
886,106 |
| 25 | Canada | Cogeco |
859,090 |
| 26 | Australia | Austar |
742,000 |
| 27 | USA | Insight Communications Company |
716,000 |
| 28 | USA | CableOne |
669,000 |
| 29 | USA | RCN Corp. |
364,000 |
| 30 | USA | WideOpenWest Networks |
360,000 |
| 31 | USA | Bresnan Communications |
306,000 |
| 32 | USA | Service Electric Cable TV Incorporated |
287,000 |
| 33 | USA | Atlantic Broadband |
277,000 |
| 34 | USA | Armstrong Cable Services |
245,000 |
| 35 | USA | Knology Holdings |
234,000 |
| 36 | USA | Midcontinent Communications |
212,000 |
| 37 | USA | Metrocast Cablevision |
182,000 |
| 38 | USA | Blue Ridge Communications |
175,000 |
| 39 | USA | Broadstripe |
157,000 |
| 40 | USA | Buckeye CableSystem |
147,781 |
| 41 | USA | General Communications |
147,701 |
| 42 | USA | Wavedivision |
141,207 |
| 43 | USA | Midocean |
139,808 |
