BT 1471 tells you the last number that called - unless the caller withheld their number by dialling '141' before dialling your number, or the call came from a switchboard extension number. 1471 Call Return also lets you return the call straight away, by pressing '3'. 1471 is always active and useful even if you have an answering machine.
It's free to use 1471 to find out the last number that called. If you press '3' to return the call there's a 26.5p charge plus the cost of the call.
It's possible to prevent a number being released when making an outgoing call by dialling the prefix '141' before the telephone number.
This means that when the BT 1471 service is used to find out which number called last, this information is not available. Instead, a recorded message will be delivered informing you that that the last caller withheld their number.
It's also possible to permanently withhold a number, and some businesses will use this by default.
There are a number of reasons why a caller might withhold their number.
For example, not all telephone lines are able to accept incoming calls. A majority of ex-directory customers withhold their number to maintain their privacy, or the caller may simply not wish to receive a return call (e.g. for a Samaritans volunteer working from home).
Only a small minority of calls are made with any malicious intent.
BT 1471 will update in the normal way if:
However, please note that 1471 will not update if a call switches to BT Answer 1571 when the line is busy.