Country
United Kingdom
Autonomous systems registered in United Kingdom, largest IPv4 address space first.
Routed networks
2,261
of 3,141 registered
IPv4 addresses
95.13M
27,987 prefixes
IPv6 prefixes
6,703
GB
Networks
| AS | Network | IPv4 addresses | IPv4 prefixes | IPv6 prefixes | Upstreams | Downstreams |
|---|---|---|---|---|---|---|
| AS5089 | Virgin Media Limited | 23.03M | 297 | 3 | 8 | 57 |
| AS2856 | British Telecommunications Limited | 18.47M | 543 | 7 | 11 | 148 |
| AS13285 | TalkTalk Communications Limited | 7.73M | 94 | 5 | 27 | 2 |
| AS786 | Jisc Services Limited | 6.97M | 209 | 7 | 20 | 24 |
| AS5607 | Sky UK Limited | 6.35M | 49 | 30 | 22 | 3 |
| AS5378 | Limited | 2.79M | 23 | 1 | 22 | 2 |
| AS6871 | British Telecommunications Limited | 2.13M | 61 | 2 | 1 | 0 |
| AS8220 | COLT Technology Services Group Limited | 1.52M | 154 | 19 | 44 | 1,076 |
| AS206067 | Hutchison 3G UK Limited | 1.10M | 309 | 93 | 24 | 0 |
| AS212238 | Datacamp Limited | 1.08M | 3,659 | 713 | 11 | 0 |
| AS8426 | Claranet Limited | 910K | 86 | 18 | 37 | 14 |
| AS8851 | GCI Network Solutions Limited | 816K | 340 | 6 | 23 | 2 |
| AS5413 | Wavenet Limited | 741K | 103 | 5 | 12 | 14 |
| AS5400 | British Telecommunications Limited | 734K | 85 | 40 | 29 | 60 |
| AS31655 | Gamma Telecom Holdings Ltd | 614K | 36 | 3 | 8 | 6 |
| AS3300 | British Telecommunications Limited | 604K | 123 | 29 | 25 | 19 |
| AS30844 | Liquid Telecommunications Ltd | 545K | 294 | 15 | 53 | 245 |
| AS13037 | Zen Internet Ltd | 528K | 37 | 1 | 16 | 3 |
| AS42689 | Glide Student & Residential Limited | 495K | 352 | 3 | 23 | 9 |
| AS20860 | IOMART CLOUD SERVICES LIMITED | 419K | 194 | 16 | 23 | 20 |
| AS15395 | Rackspace Ltd. | 405K | 75 | 1 | 1 | 0 |
| AS62240 | Clouvider Limited | 362K | 1,334 | 1,118 | 40 | 24 |
| AS8468 | Cityfibre Limited | 360K | 45 | 3 | 23 | 4 |
| AS35228 | Telefonica UK Limited | 294K | 114 | 26 | 22 | 4 |
| AS25180 | Exponential-E Ltd. | 292K | 44 | 3 | 15 | 54 |
| AS15914 | Airways plc | 278K | 53 | 0 | 3 | 0 |
| AS8698 | BUILDING SOCIETY | 262K | 109 | 0 | 5 | 0 |
| AS12390 | KCOM Group Limited | 260K | 18 | 2 | 25 | 1 |
| AS56478 | Hyperoptic Ltd | 238K | 109 | 3 | 25 | 0 |
| AS25310 | Vodafone Limited | 229K | 4 | 0 | 1 | 0 |
| AS201838 | Community Fibre Limited | 222K | 101 | 2 | 22 | 1 |
| AS8607 | Digital Space Group Limited | 206K | 20 | 4 | 10 | 3 |
| AS12703 | Pulsant (Scotland) Ltd | 180K | 60 | 7 | 28 | 24 |
| AS20712 | Andrews & Arnold Ltd | 157K | 88 | 21 | 23 | 21 |
| AS47474 | Virtual1 Limited | 153K | 16 | 1 | 1 | 11 |
| AS25369 | Hydra Communications Ltd | 153K | 297 | 18 | 45 | 37 |
| AS15404 | Technology Services Group Limited | 146K | 147 | 9 | 1 | 0 |
| AS21301 | Natwest Markets PLC | 135K | 15 | 0 | 3 | 0 |
| AS198864 | Queen Mary University of London | 133K | 5 | 2 | 1 | 0 |
| AS209237 | NPL Management LTD | 132K | 4 | 0 | 2 | 0 |
| AS8651 | MUFG Securities EMEA PLC | 131K | 10 | 0 | 4 | 0 |
| AS60068 | Datacamp Limited | 130K | 420 | 79 | 81 | 225 |
| AS41230 | ASK4 Limited | 122K | 16 | 7 | 21 | 4 |
| AS5587 | Itility Limited | 122K | 13 | 1 | 4 | 0 |
| AS41354 | ITS Technology Group Limited | 119K | 42 | 3 | 20 | 3 |
| AS6908 | Six Degrees Technology Group Limited | 113K | 43 | 6 | 3 | 13 |
| AS42831 | UK Dedicated Servers Limited | 112K | 268 | 8 | 11 | 21 |
| AS56329 | Gigaclear Limited | 111K | 31 | 3 | 23 | 0 |
| AS8586 | TalkTalk Communications Limited | 108K | 16 | 1 | 1 | 0 |
| AS21433 | Accenture UK Limited | 105K | 325 | 63 | 80 | 1 |
| AS39326 | Syntura Group Limited | 105K | 30 | 5 | 21 | 18 |
| AS13213 | THG HOSTING LIMITED | 103K | 117 | 5 | 25 | 4 |
| AS58065 | Orion Network Limited | 102K | 397 | 7 | 9 | 1 |
| AS16247 | Convergence Group (Wireless) Networks Limited | 101K | 227 | 9 | 22 | 6 |
| AS12701 | Barclays Bank plc | 100K | 33 | 0 | 9 | 0 |
| AS214143 | SKYDIGITAL TELECOM LTD | 99.33K | 281 | 0 | 7 | 0 |
| AS5503 | RM Education Ltd | 99.33K | 40 | 1 | 21 | 2 |
| AS48101 | Trooli Ltd. | 99.07K | 62 | 13 | 23 | 1 |
| AS49758 | Lloyds Banking Group PLC | 98.30K | 11 | 0 | 3 | 0 |
| AS44574 | Network Services Ltd. | 98.05K | 18 | 9 | 1 | 1 |
| AS25160 | Vorboss Limited | 97.02K | 33 | 4 | 33 | 13 |
| AS42973 | Convergence Group (Wireless) Networks Limited | 96.26K | 63 | 0 | 2 | 3 |
| AS3223 | Voxility LLP | 95.49K | 329 | 30 | 49 | 142 |
| AS21267 | Wavenet Limited | 89.60K | 63 | 1 | 22 | 1 |
| AS31515 | Inmarsat Global Limited | 87.81K | 55 | 1 | 19 | 2 |
| AS24867 | Rackspace Ltd. | 86.27K | 14 | 0 | 1 | 0 |
| AS29550 | Team Blue Carrier Limited | 86.02K | 12 | 2 | 6 | 6 |
| AS214238 | HOST TELECOM LTD | 84.22K | 329 | 0 | 6 | 0 |
| AS61323 | ANS ACADEMY LIMITED | 82.69K | 60 | 6 | 25 | 4 |
| AS2818 | BBC | 81.92K | 4 | 3 | 25 | 0 |
| AS60187 | London Grid for Learning Trust | 81.66K | 47 | 2 | 17 | 3 |
| AS51561 | ICUK Computing Services Limited | 79.87K | 71 | 2 | 24 | 2 |
| AS16082 | Spitfire Network Services Limited | 79.87K | 12 | 1 | 21 | 1 |
| AS31727 | Node4 Limited | 78.85K | 143 | 2 | 27 | 6 |
| AS4455 | IX Reach Ltd | 73.22K | 46 | 15 | 54 | 77 |
| AS35575 | Vaioni Group Ltd | 73.22K | 36 | 2 | 22 | 3 |
| AS24775 | Qinetiq Limited | 69.63K | 2 | 0 | 2 | 0 |
| AS21054 | Natwest Markets PLC | 69.38K | 11 | 0 | 3 | 0 |
| AS30740 | Exa Networks Limited | 67.07K | 4 | 1 | 22 | 4 |
| AS50292 | Access UK Ltd | 66.82K | 37 | 0 | 4 | 1 |
| AS15601 | Investment Services Ltd | 66.56K | 2 | 0 | 3 | 0 |
| AS21296 | Pricewaterhousecoopers Services Limited | 66.05K | 3 | 0 | 1 | 0 |
| AS39400 | London Borough of Hackney | 65.79K | 2 | 0 | 1 | 0 |
| AS201773 | University of Warwick | 65.79K | 2 | 0 | 1 | 0 |
| AS212655 | YouFibre Limited | 65.28K | 37 | 3 | 26 | 1 |
| AS202596 | GNC Realisations 2026 Limited | 64.26K | 49 | 0 | 17 | 0 |
| AS215540 | GLOBAL CONNECTIVITY SOLUTIONS LLP | 63.49K | 237 | 37 | 11 | 1 |
| AS212465 | Comcast International Holdings UK Limited | 62.46K | 12 | 8 | 3 | 0 |
| AS8435 | Lloyds Banking Group PLC | 60.67K | 47 | 0 | 4 | 2 |
| AS29107 | Synapse Network LTD | 58.88K | 23 | 2 | 6 | 5 |
| AS59395 | Southern Communications Ltd | 57.86K | 27 | 4 | 24 | 3 |
| AS205544 | Leaseweb UK Limited | 56.83K | 65 | 31 | 5 | 0 |
| AS5482 | AllPoints Fibre Limited | 56.32K | 15 | 16 | 20 | 3 |
| AS35425 | Iomart Managed Services Limited | 55.81K | 22 | 4 | 1 | 0 |
| AS25577 | MAINFRAME & CYBERNETIC SYSTEMS LIMITED | 55.04K | 53 | 1 | 23 | 9 |
| AS15533 | Redcentric Solutions Ltd | 52.48K | 15 | 2 | 1 | 3 |
| AS41564 | Orion Network Limited | 52.22K | 198 | 7 | 12 | 7 |
| AS61112 | AKILE LTD | 50.94K | 145 | 32 | 13 | 3 |
| AS39356 | Avanti Broadband Ltd | 50.94K | 6 | 4 | 22 | 1 |
| AS44444 | Forcepoint UK Limited | 50.69K | 198 | 2 | 39 | 1 |
Registration country comes from the regional registries' delegation files. A network registered here may announce space used anywhere.