You might also consider giving them the option to skip your voicemail message completely by pressing another key (again, check with IT). You also want to make callers aware what you will return their call, instead of telling them that you will try to return their call--and let them know when you are likely to do it, if possible. If necessary, provide additional or emergency information in your voicemail greetings. My dentist, for example, lists his cell phone number for emergencies.
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4. "Hello, you've reached [your name and title]. I'm currently out on parental leave until [date]. In the meantime, please direct all phone calls to [alternate contact name] at [phone number] and emails to [email address]. Thanks, and I'll see you in [month you'll be back in the office]."
Voicemails need to maintain a professional consistency that’s aligned with the entity it’s representing. That said, the structure can vary depending on the situation. There’s no template set in stone. In fact, trite and generic should be off the table. The goal should be a balance of uniqueness and practicality.