How to get around the hidden costs of voicemail
7 June 2012 Last updated at 15:59 BST
Many phone users think that calls to voicemail are included in their contracts but some customers may be running up significant charges without realising.
Some carrier companies charge more than the cost of making a phone call.
BBC Radio 5 live's Shelagh Fogarty and Dominic Laurie got tips from Dominic Balisezewski, a telecoms expert at broadbandchoices.co.uk.
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