Telephone Charging Rates

As applied by BT

Written by Clive Feather

Last updated 2009-06-25


Many telephone companies charge the same prices for calls to all geographic (those beginning 01 and 02) and pseudo-geographic numbers (03). However, that didn't always used to be the case, and some companies still distinguish between "local" and other numbers. This page discusses the meaning of "local" and related terms, at least how they were applied by BT. Much of this page uses the present tense, because the concepts still exist even though they have no practical use.

In my work over the years, I discovered that a lot of people didn't really understand how the phone calls they made were charged. For example, many people believed that a phone call was more expensive if they dialled a number beginning 0. While it is true that all long-distance calls do begin with 0, so do many local calls.

(For those unclear about this concept, it is possible to omit the dialling code if it is the same as your own and begins 01 or 02. So if your phone number begins 020, then you can dial 7222 1234 rather than 020 7222 1234. Furthermore, there used to be a series of "local codes". Thus from 0223 (now 01223) numbers, it was possible to dial 92 instead of 0638 and 93 instead of 0954. Contrary to some people's belief, it made no difference to the cost whether you used the full code or the local code.

Before we start ...

This material has been compiled from various sources. It is correct to the best of my knowledge, but I take no responsibility for any use made of it. This page is not sponsored, supported, or otherwise connected with BT other than through use of publically available BT material.

Some other telephone companies use the same method of charging as BT, or a variation thereon. Others do not. You should contact your telephone company for specific details of how they charge for calls. Furthermore, this material only applies to calls between geographic numbers, and not mobile or personal numbers or other services. For an example of the range of non-geographical numbers, and the different rates that apply, see the Kingston Communications tariff.

I would like to know of any errors in the information presented. The best form of evidence is an extract from a telephone bill. Nearly as good is an extract from the local telephone directory, though these have been known to contain mistakes. In both cases, please email me a scanned-in image or a pointer to an image. I do not consider statements made by BT operators to be evidence; I have far too many examples of when they have given wrong, or even nonsense, answers.

Types of call

The BT charging system has three types of call: local, regional, and national. Local calls are generally cheaper than regional ones, which in turn are cheaper (or sometimes the same price as) national ones. Of course, the cost of a call also varies according to the time of day and the day of the week.

On 1999-10-01 BT made the regional and national rates the same for all calls, and on 2000-12-20 they formally abolished the distinction.

Charge groups

BT divide the United Kingdom into 637 "charge groups", each with a name and a reference number. In theory, each group covers a particular area, and (it is claimed) the boundaries between the groups are regularly adjusted. However, it is not actually necessary to know the boundaries, as it is always possible to tell which charge group a phone belongs to by the first 4, 5, or 6 digits of its number.

Some charge groups cover a single dialling code while others cover more than one, and some dialling codes are split into several groups. For example:

Relating call types to charge groups

All calls between numbers in the same charge group are local calls. However, the converse is not true. If two charge groups touch each other, then a call between them is also local. The catch, of course, is determining which charge groups do touch. It ought to be simple to decide, but there are a number of problems. Firstly, BT do not publish maps of charge group boundaries, claiming that there are tens or hundreds of changes each month. Then there are a number of marginal cases. If two charge groups are on the opposite side of a bay or river estuary, there is no easy way to tell if they "touch" or not. Furthermore, sometimes four, rather than three, groups appear to be about to meet at the same place. Sometimes all four are local to each other, and sometimes there is one pair which are not. And finally, there are a number of explicit special cases where calls are made local in order to bind a community together.

While local calls are defined in terms of charge group boundaries, regional and national calls are not. Instead, each charge group is given a location known as its charging point. If two charge groups are not local to each other, it is necessary to determine the distance between their charging points. If this is under 56.4km, calls between them are regional; otherwise they are national. Naturally, BT do not publicise the actual locations of the charging points.

Finally, the Republic of Ireland adds yet another special case. Calls from Great Britain (England, Scotland, and Wales) to the Republic are charged at a special "Irish" rate. But calls from Northern Ireland are charged on the same basis as calls within the UK - a charge group in Northern Ireland may be a local call, a regional call, or a national call to a given charge group in the Republic. In particular, there are cross-border local calls.

Finding your charge group

For more information about the charge group a number is in, and what groups it is local to, find the first few digits in the following list.

00   010  
0110   0111   0112   0113   0114   0115   0116   0117   0118   0119  
0120   0121   0122   0123   0124   0125   0126   0127   0128   0129  
0130   0131   0132   0133   0134   0135   0136   0137   0138   0139  
0140   0141   0142   0143   0144   0145   0146   0147   0148   0149  
0150   0151   0152   0153   0154   0155   0156   0157   0158   0159  
0160   0161   0162   0163   0164   0165   0166   0167   0168   0169  
0170   0171   0172   0173   0174   0175   0176   0177   0178   0179  
0180   0181   0182   0183   0184   0185   0186   0187   0188   0189  
0190   0191   0192   0193   0194   0195   0196   0197   0198   0199  
020 021 022 023 024 025 026 027 028 029
03   04   05   06   07   08   09  

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