Reiterate the main point of your message and repeat your name and phone number. This will help the receiver remember your name and message and spares him from having to listen from the beginning to write down your contact information.
A voicemail greeting can be pivotal in attracting a potential customer to your company or repelling him! So, it may be worthwhile to utilize some tried and tested tips to frame voicemail greetings for your company. The first line must include a brief description of your company and the services it offers clearly. Tell the callers the time frame within which they will get a call from your end. Ensure the voice used in recording the greeting is cheerful and not drab one. Ensure the greeting is recorded not in a hurried manner so that the callers can understand each word without issues. Try keeping the voicemail message length to 20 seconds or so.

Expand your message with 'We're sorry we couldn't take your call this time.' The inclusion of 'this time' or 'on this occasion' suggests that the voicemail is the exception rather than the rule.
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