Simply speak into your phone or computer while recording a greeting with your business phone service. If you need to create your own audio file, the voice memo app on your phone should do fine.
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A good voicemail greeting is short and professional, lets people know that you’ll get back to them, and invites callers to continue engaging with a call-to-action. You should also show your personality if you’re in an industry or role that allows that. If your industry is more conservative, however, you’ll want to keep humor and personal touches to a minimum. A greeting Your name Your company A simple explanation for missing the call (e.g. you’re away from the phone or are on holiday) A rough estimate of when you’ll get back to the person An alternative person to reach out to (if you’re out of office) An alternative mode of communication (if you prefer email or text) A call-to-action such as “Leave a message” or “Send me an email at [email protected]”
Why not shorter than 20 seconds? The voicemail indicator will tell the contact how long the message is, and if it’s just 5 or 10 seconds, it may seem like a spam call or a wrong number, which means they won’t listen to it at all. Messages between 20 and 30 seconds seem important enough to listen to but not so long that they’re off-putting for the contact.