Area Code +44-8721-(830000...839999) located in Special Services higher rate: up to and including 10p for BT customers (non-internet), more detail is as below.
Place
Other Information
Dialling Instructions
For trunk calls: 0 8721 830000 (Trunk Code + National Destination Code + Subscriber Number)
For international calls: 00 44 8721 830000 (International Prefix + International Dailing Code +National Destination Code + Subscriber Number)
Telephone Number List
830000 ~ 839999 (Count: 10,000)
Example:
+44-8721-830000 / 0044-8721-830000 (08721-830000 / 0-8721-830000)
+44-8721-830001 / 0044-8721-830001 (08721-830001 / 0-8721-830001)
+44-8721-830002 / 0044-8721-830002 (08721-830002 / 0-8721-830002)
+44-8721-830003 / 0044-8721-830003 (08721-830003 / 0-8721-830003)
+44-8721-830004 / 0044-8721-830004 (08721-830004 / 0-8721-830004)
... +44-8721-xxxxxx / 0044-8721-xxxxxx (08721-xxxxxx / 0-8721-xxxxxx)
... +44-8721-839995 / 0044-8721-839995 (08721-839995 / 0-8721-839995)
+44-8721-839996 / 0044-8721-839996 (08721-839996 / 0-8721-839996)
+44-8721-839997 / 0044-8721-839997 (08721-839997 / 0-8721-839997)
+44-8721-839998 / 0044-8721-839998 (08721-839998 / 0-8721-839998)
+44-8721-839999 / 0044-8721-839999 (08721-839999 / 0-8721-839999)