Keep it Brief. Time is money in business, so if your voicemail is long, chances are the caller will simply disengage before the cue to leave a message even sounds. Keep your voicemail short. The most should be around 30 seconds, and even that’s pressing it. We’ve grown into a country where our attention span can last only about 10 seconds in some cases, so keep it short, brief and to the point. Persuade and Engage the Caller. If someone calls your business, they already have an intention. It’s the quality of your voicemail that plays a factor if they consider you a company they’d like to deal with. This is your chance to motivate someone to engage in a meaningful conversation with you. If your voicemail is shoddy, chances are they’ll hang up, or lose motivation to continue the call. In other words, your voice mail must engage and entice someone to the point that they care enough to leave you a message.
30. Hello, you’ve reached [your name]. I’m currently out of the office and will return on [X date]. If your call requires urgent attention, please call [Name] at [phone number] and they’ll be happy to assist you. If not, leave a message and I’ll return your call when I get back.

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One cool iOS feature is called Visual Voicemail. This is Apple’s attempt to make voicemail less annoying. Visual Voicemail allows you to see a transcription of the voicemail the caller left. This transcription allows you to read their voicemail as if it were a text message.