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.
Creating a voicemail greeting might not be fun, but with the scripts I’ve shared, you should have an easier time. No need to practice time and time again — simply plug in your name, company title, and other details, then read it out loud to your phone’s voicemail greeting recorder. With a professional greeting, you’ll continue nurturing prospects even if you don’t pick up the phone.

A separate after-hours attendant menu can inform callers that your office is closed, state your business’ operating hours, and provide options that callers can immediately act upon. For example, you can direct them to your website for FAQs. If your business provides an account login page, remind your customers that they can login at any time to get general account information. In this situation, be proactive.
Some people might be willing to call you again later. But everyone else is either going to just give up or turn to one of your competitors.