Proper telephone etiquette is essential for presenting a professional image and keeping an office running smoothly. Getting the nuances right is important, since a phone call usually represents a customer's first encounter with the company. These same unwritten rules also apply to coworker relationships, where one rude person can easily disrupt an otherwise harmonious environment. Learning the basic ground rules of office telephone etiquette now will save you from embarrassment later.

Announce Yourself Promptly

Don't leave callers guessing at your identity in answering them. Respond with your full name and the formal company greeting, if your employer requires one. For example, a front office receptionist might say something like, "Good morning, this is Jane Doe speaking, how may I help you?" Never eat or chew gum while you're on the phone. If the caller is leaving a message, repeat the details aloud, so he knows you understand them. Note each call's time and date before turning in the message slip.

Curb Your Speakerphone

Restrict speakerphones to private settings like conference calls, where it's easy to contain volume levels behind closed doors. Keep them out of cubicles or open spaces to avoid disturbing coworkers. In doing business, make sure that all parties know you're using a speakerphone and get their agreement before starting. Once a meeting ends, make sure you've really disconnected the speakerphone to keep nonparticipants from hearing any casual comments that you or others make.

Ditch the Headphones

Keep headphones or Bluetooth headsets on your desk when you leave it for any length of time, such as using the restroom or taking a personal break in a common area. Otherwise, coworkers will struggle to get your attention, since they'll have no idea if you're taking a call. Wearing earpieces or headphones when you're not using them is also rude, since it suggests you're not willing to engage with other people.

Lower the Volume

Never lose track of your surroundings while you're on the phone. Speak in quiet, conversational tones at all times -- but lower your voice if coworkers flash irritated looks, advises Barbara Pachter, a career coach interviewed in Business Insider's October 2013 article "Eight Phone Etiquette Rules Every Professional Should Know." Follow similar rules for devices like cell phones. Leave them on vibrate to avoid disrupting work functions, and choose normal ringtones. Coworkers may not share your love of abrasive hip-hop or speed metal, for instance.

Mind Your Voicemails

State your name, title and instructions for callers in voicemail greetings. Follow your employer's user guidelines. For example, the University of the Pacific requires employees to regularly update their greetings -- so callers don't wonder if a worker is still on vacation. Be succinct in your voice messages, since the recipient may not have time to hear more than basic details. Say your phone number slowly, however, so the caller doesn't end up replaying your message over and over.