You can do this by registering for Caller Display. It won’t stop incoming calls, but will show you the caller’s number (as long as it isn’t withheld or unknown). This means you’ll know who’s calling you, and be able to choose whether or not to take the call.
Can I check who’s calling me before answering my home phone?
To get this service, just call us on 08080 034515. Calls are free from landlines and Vodafone mobiles, and charged at your operator’s standard rate from other mobiles.