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AS2856 BT-UK-AS British Telecommunications Limited

Everything the routing table and the registries say about AS2856: who holds it, which registry issued it, and which address blocks it advertises.

Consumer and business ISPsAS2856

534 IPv4 and 7 IPv6 prefixes announced.

Registry facts

Refreshed daily
AS number
AS2856
Holder
BT-UK-AS British Telecommunications Limited
Country
Not published
Regional registry
RIPE — RIPE Network Coordination Centre
Registry block
2830-2879 (IANA 16-bit Autonomous System (AS) Numbers Registry)
Announced today
Yes
IPv4 prefixes
534
IPv6 prefixes
7
Observed at
2026-09-05T16:00:00

Data: RIPEstat. Prefix and holder data comes from the RIPEstat Data API and is cached for 24 hours. The regional registry is derived from the IANA AS number allocation table. Authoritative registry records are served by RIPE RDAP.

Announced prefixes

534 IPv4 · 7 IPv6
  • 193 IPv4 shown
  • 7 IPv6 shown
  • 5.35.192.0/21
  • 5.80.0.0/15
  • 5.81.0.0/16
  • 5.181.136.0/24
  • 9.151.0.0/19
  • 9.151.208.0/20
  • 9.151.248.0/21
  • 9.232.192.0/18
  • 9.233.48.0/20
  • 9.237.96.0/19
  • 9.237.128.0/18
  • 9.237.192.0/19
  • 15.145.20.0/22
  • 23.26.70.0/24
  • 23.26.108.0/24
  • 23.26.117.0/24
  • 23.26.131.0/24
  • 23.26.192.0/24
  • 23.27.32.0/24
  • 23.27.33.0/24
  • 23.27.34.0/24
  • 23.27.35.0/24
  • 23.27.36.0/24
  • 23.27.37.0/24
  • 23.27.38.0/24
  • 23.27.39.0/24
  • 23.27.40.0/24
  • 23.27.102.0/24
  • 23.27.103.0/24
  • 23.27.104.0/24
  • 23.27.105.0/24
  • 23.27.106.0/24
  • 23.27.107.0/24
  • 23.27.108.0/24
  • 23.230.82.0/23
  • 23.230.242.0/24
  • 23.230.252.0/24
  • 31.48.0.0/13
  • 31.90.0.0/15
  • 31.92.0.0/15
  • 31.94.0.0/16
  • 31.96.0.0/16
  • 31.100.0.0/14
  • 31.104.0.0/16
  • 31.106.0.0/15
  • 31.112.0.0/14
  • 31.116.0.0/14
  • 31.116.0.0/16
  • 31.117.0.0/16
  • 31.118.0.0/16
  • 31.119.0.0/16
  • 31.120.0.0/16
  • 31.121.0.0/16
  • 31.122.0.0/15
  • 31.124.0.0/16
  • 31.126.0.0/15
  • 31.130.240.0/23
  • 37.44.229.0/24
  • 37.44.230.0/24
  • 37.44.231.0/24
  • 37.97.112.0/22
  • 37.143.0.0/22
  • 37.230.61.0/24
  • 40.27.28.0/24
  • 40.27.72.0/24
  • 45.39.116.0/24
  • 45.39.188.0/24
  • 45.149.7.0/24
  • 45.149.168.0/23
  • 45.149.170.0/23
  • 46.68.0.0/15
  • 46.68.66.0/24
  • 46.248.96.0/22
  • 46.248.102.0/23
  • 46.248.104.0/23
  • 46.248.120.0/22
  • 50.117.7.0/24
  • 50.117.51.0/24
  • 50.118.154.0/23
  • 51.14.0.0/16
  • 51.64.32.0/24
  • 51.64.34.0/24
  • 51.64.35.0/24
  • 51.146.44.0/22
  • 51.146.128.0/22
  • 51.146.136.0/22
  • 51.146.235.0/24
  • 51.146.252.0/22
  • 51.149.18.0/24
  • 51.149.19.0/24
  • 51.194.36.0/23
  • 51.194.100.0/22
  • 51.230.0.0/20
  • 51.230.16.0/20
  • 51.230.32.0/20
  • 51.230.48.0/20
  • 51.230.64.0/20
  • 51.230.80.0/20
  • 51.230.96.0/20
  • 51.230.112.0/20
  • 51.230.255.0/24
  • 51.241.3.0/24
  • 51.241.201.0/24
  • 62.6.0.0/16
  • 62.7.0.0/16
  • 62.172.0.0/16
  • 62.192.124.0/23
  • 62.239.0.0/16
  • 62.244.11.0/24
  • 62.244.12.0/24
  • 62.244.29.0/24
  • 62.244.36.0/24
  • 62.244.37.0/24
  • 62.244.41.0/24
  • 62.244.43.0/24
  • 62.244.45.0/24
  • 62.244.56.0/24
  • 64.205.136.0/22
  • 64.205.144.0/22
  • 72.9.180.0/22
  • 77.90.135.0/24
  • 77.90.138.0/24
  • 77.90.145.0/24
  • 77.90.151.0/24
  • 77.90.153.0/24
  • 77.90.164.0/24
  • 77.90.184.0/24
  • 77.94.224.0/24
  • 78.105.97.0/24
  • 78.105.136.0/22
  • 78.105.151.0/24
  • 78.105.175.0/24
  • 78.105.179.0/24
  • 78.105.188.0/24
  • 78.105.191.0/24
  • 78.105.194.0/24
  • 78.105.198.0/24
  • 78.105.200.0/24
  • 78.105.202.0/24
  • 79.132.64.0/24
  • 79.132.65.0/24
  • 79.139.52.0/23
  • 79.139.54.0/23
  • 80.81.58.0/24
  • 81.128.0.0/11
  • 81.128.0.0/12
  • 81.161.52.0/22
  • 82.38.9.0/24
  • 82.38.56.0/22
  • 82.39.173.0/24
  • 82.41.112.0/22
  • 82.108.4.0/22
  • 82.108.32.0/21
  • 82.108.44.0/22
  • 82.108.52.0/22
  • 82.108.68.0/22
  • 82.108.88.0/23
  • 82.108.92.0/22
  • 82.108.102.0/23
  • 82.108.116.0/22
  • 82.108.140.0/22
  • 82.108.152.0/23
  • 82.136.54.0/23
  • 82.140.134.0/24
  • 82.140.138.0/24
  • 82.140.143.0/24
  • 82.140.170.0/24
  • 82.153.33.0/24
  • 82.153.85.0/24
  • 82.153.88.0/24
  • 82.153.179.0/24
  • 82.153.181.0/24
  • 82.153.190.0/24
  • 82.153.238.0/24
  • 83.223.153.0/24
  • 83.223.154.0/24
  • 83.245.16.0/21
  • 83.245.24.0/22
  • 84.23.0.0/19
  • 84.46.177.0/24
  • 84.46.181.0/24
  • 84.46.183.0/24
  • 84.46.188.0/24
  • 84.46.190.0/24
  • 84.46.191.0/24
  • 84.46.194.0/24
  • 84.55.17.0/24
  • 84.55.22.0/24
  • 85.88.224.0/20
  • 85.88.240.0/23
  • 85.189.72.0/23
  • 85.189.74.0/23
  • 85.189.76.0/23
  • 2001:4878:c259::/48
  • 2a00:2380::/25
  • 2a01:4c8::/29
  • 2a01:4c8:f400::/48
  • 2a01:4c8:f401::/48
  • 2a02:ee80:4176::/47
  • 2a03:1e82:90ff::/48

A prefix here is a block this AS was seen originating in BGP, not a block it is guaranteed to own. Announcement and allocation are different facts, and they disagree more often than people expect.

Registry record

ripe
FieldValue
aut-num2856
as-nameBT-UK-AS
descrBTnet UK Regional network
orgORG-BPIS1-RIPE
mp-importfrom AS5400 action pref=10; accept AS-BT-EU
mp-importfrom AS5400 action pref=14; accept ANY
mp-exportto AS-ANY announce AS-BTGB
mp-importfrom AS702 action pref=11; accept AS702:RS-UK
mp-importfrom AS714 action pref=11; accept AS714
mp-importfrom AS786 action pref=11; accept AS-JANETPLUS
mp-importafi ipv4.unicast from AS1248 action pref=11; accept AS-HERE
mp-importafi ipv4.unicast from AS1267 action pref=11; accept AS-INFOSTRADA
mp-importfrom AS2119 action pref=11; accept AS-TELENOR
mp-importafi ipv4.unicast from AS2529 action pref=11; accept AS2529
mp-importfrom AS2818 action pref=11; accept AS-BBC
mp-importfrom AS2906 action pref=11; accept AS2906
mp-importfrom AS3223 action pref=11; accept AS3223
mp-importfrom AS3303 action pref=11; accept AS-SWCMGLOBAL
mp-importfrom AS4766 action pref=11; accept AS4766
mp-importafi ipv4.unicast from AS4788 action pref=11; accept AS4788
mp-importafi ipv4.unicast from AS5089 action pref=11; accept AS-NTLI
mp-importfrom AS5413 action pref=11; accept AS5413
mp-importfrom AS5459 action pref=11; accept AS-LINX
mp-importafi ipv4.unicast from AS5466 action pref=11; accept AS-EIRCOM

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