Internet telephony soared in popularity during 1999, with more than 12 times the number of calls made over the Internet last year than in 1998.

Two and a half billion telephone calls were made using voice-over-Internet-protocol (VoIP) in 1999. This amounts to an increase of 2.3 billion calls over the last 12 months. According to Probe Research, as many as four billion calls could be made using VoIP in 2000. Although the Internet telephony market remains small in comparison with that of traditional phone networks, which channelled 7 trillion minutes of calls in 1999, Probe analysts believe the increased use of VoIP is significant. Calls made over the Internet are considerably cheaper than traditional phone calls and some US companies are actually offering free VoIP, profiting from offering space to advertisers rather than charging customers. VoIP providers offered improved sound quality during 1999 and made a number of new services available including unified messaging, which allows customers to check email, voicemail, pager messages and faxes at one source.