Website: https://www.openphone.co/blog/professional-business-voicemail-greetings/
It’s important to ensure the content is informative and relevant to the caller. And the rule ‘less is more’ very much applies to writing for the ear. It’s important to keep the sentences short and to the point. A popular way to get a message across is follow this structure: Introduce the topic in the first sentence e.g. Did you know that BusinessCo now offers no contract plans for hosted PBX and business VoIP? Explain how the information will benefit the caller in the second sentence e.g. And that means complete flexibility for your business and no long-term commitments. Wrap up with a call to action in the third sentence e.g. To find out more, visit our website businesspbx.com.au or speak to one of our Business Consultants when you come off hold.

When you create a professional voicemail greeting, it can be a good idea to think about what your callers might want to know. After doing so, you can make a list of points to cover in your voice message; it might also be a good idea to write out the entire greeting on a piece of paper. The ideal message should be somewhere between 10 and 20 seconds, so you may want to time yourself repeating your message before you record it. After composing your telephone message, it can be a good idea to get a second opinion of this greeting so you can make sure it sounds professional. Writing down a voicemail greeting helps prevent mistakes when recording it.
A relatively unprofessional one — like mine, for instance — does the opposite: It encourages prospects, recruiters, and potential connections to run in the other direction.