An extension number typically follows the standard phone number for a business, for example: 800-555-5555 ext. 453. The purpose of an extension number is to direct phone calls to specific persons or departments, which helps streamline the system for incoming phone calls. If you are dialing a phone number with an extension, you may bypass traditional methods of waiting to tell the automatic, or real-life, operator the extension by straight dialing the extension number.
Dial the standard 10-digit phone number, and wait for the phone to ring once.
Dial the extension number immediately following the first ring. This method of making a straight call to an extension number only works for phone systems that do not require special characters before or after you enter the extension. For example, some phone systems require you to enter the "#" key either before or after the extension number. If this is the case, you may not be able to directly dial the extension number without waiting for the prompt.
Dial the extension number, without the 10-digit standard number, if you're calling a phone within the same telephone network. For example, if you work in cubicle A and wish to contact the employee in cubicle C, pick up the phone and cubicle C's extension number. This will immediately transfer you to his phone.