A good cell phone voice mail greeting is clear, courteous and to the point. Enunciate, don't mumble, to make it as easy as possible for those with poor hearing or bad connections to be able to hear your greeting. Be polite, and save swearing for the conversation, if applicable.
Voicemails don’t necessarily have to be monotonous or extremely jazzy or funky. What you should be looking for is a balance between the two. Whenever you call someone and their voicemail greeting is playing, it tells you a lot about who they are, as a person. Which is why, you’ve got to put a little bit of “you” when it comes to voicemail. And the best part about all of this is, since you couldn’t come to the phone, at least the callers are having a good time listening to the message.

Your voicemail needs to have relevant information such as your name, who the prospects are connecting to, the department you work in, why your not available to assist your prospects, when you will call them and related information, this is what the prospects would prefer hearing instead of dragging the voicemail messages speaking about your brand and more.
Please leave a message with your name and phone number, and I will return your call as soon as possible. Thank you. Informal voicemail greetings. Some businesses are in the “business” of being less formal than a law firm, for example. And that’s okay. Informal greetings can be more approachable, as if someone is calling a friend.