AS21054 UK-NATWEST-AS21054 Natwest Markets PLC

UK-NATWEST-AS21054 Natwest Markets PLC · registered in the United Kingdom

IPv4 addresses60,67221 prefixes · 0.002% of announced IPv4

Rank in United Kingdom#80largest network in GB by IPv4 space, of 2,074 · 0.09% of GB

Rank worldwide#3,639of 79,396 networks with IPv4

IPv6noneno IPv6 routes announced

CountryUnited Kingdom2,261 ASNs registered there

Open AS21054 in ASN lookup Look up an IP in this network (155.136.0.1) All networks in United Kingdom

IPv4 prefixes

All 21 prefixes, in address order.

155.136.0.0/19
155.136.32.0/20
155.136.48.0/21
155.136.60.0/22
155.136.64.0/18
155.136.128.0/20
155.136.145.0/24
155.136.147.0/24
155.136.148.0/23
155.136.150.0/24
155.136.152.0/21
155.136.160.0/19
155.136.192.0/22
155.136.196.0/23
155.136.202.0/23
155.136.204.0/22
155.136.208.0/20
155.136.228.0/23
155.136.234.0/23
155.136.236.0/22
155.136.240.0/20

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IP-to-ASN data: iptoasn.com (public domain). Snapshot downloaded 2026-11-11, refreshed daily. Ranges are what each network announces in BGP, not registry allocations. Data sources