Each carrier has a different method for setting up voicemail, and we’ve provided a brief description of how to do it (and where to find instructions) where applicable below.
You can also delete messages without having to dial into the normal voicemail system. Unfortunately, UK networks have been slow to adopt Visual Voicemail, and it currently just seems to be O2, EE and Orange that offer it to iPhone users. It’s not available from major networks such as 3 and T-Mobile (even though T-Mobile is now owned by EE).

The much safer option is to do this with a third-party voice mail system like Google Voice (but the voicemail recordings are limited to 3 minutes). So it's better to have a paid voicemail service, use the Google Voice recording option for incoming calls outlined above, or spring for the paid recorder services like Recordator.
The importance of voicemail in the customer care sector has not diminished despite the arrival of newer web technologies. VoIP applications let the businesses use voicemail service with flexibility, as it is. The users need not rely on extension terminals when they use VoIP services. A strong internet connection is a prerequisite and the pre-configured phones can be used – both for calling /receiving calls and for automated custom greetings. IVR feature redirect callers to the right virtual extension where their needs can be addressed. This can be done anywhere through a web portal access and an internet connection.