The default, generic voicemail greeting that comes with your iPhone is fine but also rather bland and boring. You can personalize the voicemail greeting on iPhone by recording your own custom version of it. This is a tutorial on how to create a custom iPhone Voicemail greeting.
20. "Hey there, this is [your name] from [your company]. I'm out of the office until [date]. In the meantime, please direct your inquiries to [coworker's name] at [email address]. They can also be reached at [phone number]. Thank you."

Our voicemail prompts and recordings allow you to guide callers through the phone system in a number of ways. Important information can be imparted while your caller is on hold, such as queue times and caller number. You can even up your marketing game by using this opportunity to build interest about products and services you offer.
Creating a professional voicemail greeting isn’t complicated, but you need to keep a few things in mind to ensure success. The following tips will help: Be friendly and welcoming - let your company's personality shine!; Have a clear voice, speak at a slow to moderate pace, minimize background noise; Ensure the greeting is human and approachable; Keep the greeting short and informative; Ensure the greeting doesn’t sound robotic or unnatural; Show your gratitude for the call by saying thank you; Manage expectations by clearly stating when the client can expect a callback.