BT IP Ranges
BT is a consumer and business internet provider. Its network is registered under AS2856 with RIPE, and it announces 490 IPv4 prefixes to the global routing table.
- Provider
- BT
- Primary ASN
- AS2856
- Category
- ISP
- Headquarters
- London, UK
- Announced IPv4 prefixes
- 490
- Registry
- RIPE
Known IP ranges
These prefixes are currently announced to the global routing table by AS2856 (BT-UK-AS British Telecommunications PLC). Prefix sets change over time - use WHOIS Lookup for the authoritative record on any specific address.
86.128.0.0/10
86.128.0.0/11
81.128.0.0/11
86.128.0.0/12
109.144.0.0/12
217.32.0.0/12
81.128.0.0/12
95.144.0.0/13
31.48.0.0/13
194.72.0.0/14
2a00:2380::/25
2a01:4c8::/29
2a02:ee80:4176::/47 (IPv6)
What does a BT IP mean in a privacy test?
Seeing a BT IP address as your visible address means you are connecting directly through your BT line with no VPN active. If you expected a VPN exit, this tells you the tunnel is not carrying your traffic.
Related tools
Frequently asked questions
What IP ranges does BT use?
BT announces 490 IPv4 prefixes and 7 IPv6 prefixes under AS2856. Larger blocks include 86.128.0.0/10, 86.128.0.0/11, 81.128.0.0/11. The full current list is published by RIPE, and prefixes change as the network grows.
Why does a BT IP appear in my privacy test?
Seeing a BT IP address as your visible address means you are connecting directly through your BT line with no VPN active. If you expected a VPN exit, this tells you the tunnel is not carrying your traffic.
How large is the BT network?
By CAIDA's AS Rank, AS2856 reaches 152 networks through its customer cone, covering roughly 18.9 million IPv4 addresses. That places it at global rank 330 among all autonomous systems.
How do I look up a BT IP address?
Enter the address in the MyIPScan IP Geolocation Lookup. Addresses in this network return AS2856 (BT-UK-AS British Telecommunications PLC). WHOIS Lookup shows the registered CIDR block for any specific address.
What ASN does BT use?
BT operates AS2856, registered with RIPE and held by BT-UK-AS British Telecommunications PLC. In a privacy test this ASN is what identifies traffic as belonging to their network.