List of the top 20 organizations with the largest IP allocations in United Kingdom
| Rank | Name | IPv4 addresses | IPv6 /64 networks | AS numbers | Prefixes |
|---|---|---|---|---|---|
| Virgin Media Limited | 23,026,944 | 1.01 x 239 | 1 | 298 | |
| British Telecommunications PLC | 21,388,288 | 1.04 x 242 | 4 | 763 | |
| TalkTalk Communications Limited | 7,833,088 | 1.59 x 237 | 2 | 116 | |
| 4 | Jisc Services Limited | 7,178,496 | 1.63 x 236 | 1 | 223 |
| 5 | Sky UK Limited | 6,894,336 | 1.58 x 237 | 3 | 86 |
| 6 | Vodafone Limited | 3,063,040 | 1.13 x 235 | 3 | 54 |
| 7 | COLT Technology Services Group Limited | 1,666,816 | 1.77 x 234 | 3 | 340 |
| 8 | Datacamp Limited | 1,241,600 | 1.26 x 241 | 3 | 5,034 |
| 9 | Hutchison 3G UK Limited | 1,105,408 | 1.16 x 233 | 2 | 405 |
| 10 | Claranet Limited | 910,848 | 1.33 x 237 | 2 | 106 |
| 11 | Wavenet Limited | 847,888 | 1.19 x 236 | 3 | 177 |
| 12 | GCI Network Solutions Limited | 820,736 | 1.25 x 236 | 1 | 350 |
| 13 | Gamma Telecom Holdings Ltd | 616,448 | 1.5 x 236 | 3 | 47 |
| 14 | British Telecommunications Limited | 604,416 | 1.49 x 233 | 1 | 152 |
| 15 | Liquid Telecommunications Ltd | 562,944 | 1.37 x 235 | 2 | 2,230 |
| 16 | Zen Internet Ltd | 527,616 | 235 | 1 | 38 |
| 17 | Rackspace Ltd. | 526,792 | 1.5 x 233 | 5 | 103 |
| 18 | Glide Student & Residential Limited | 503,808 | 1.56 x 236 | 2 | 373 |
| 19 | IOMART CLOUD SERVICES LIMITED | 420,352 | 1.07 x 236 | 2 | 220 |
| 20 | Clouvider Limited | 380,416 | 1.11 x 238 | 9 | 2,653 |