The telephone has a speaker and microphone (not on 1403 phones) which you can control using the 
SPEAKER button.
•To make and answer calls handsfree, use the SPEAKER button in the same way as lifting or replacing the handset. The button is lit while the phone is in handsfree mode.
•When you make or answer calls by first pressing an Intercom, Call Appearance or Line Appearance button, the call is automatically connected either on the speaker or headset. Which is used is set by the phone's Default Hands Audio Path setting.
•If already using the handset, you can switch to handsfree by pressing SPEAKER. You can then replace the handset.
•If already connected to a call handsfree, lifting the handset will end the handsfree.
Note
Room acoustics and background noise can affect the proper operation of the speakerphone. To ensure that your speakerphone works effectively, follow these guidelines:
•Avoid placing your telephone in areas with high background noise caused by sources such as motor vehicles, manufacturing equipment, loud voices, radios, printers, copiers, typewriters, other noisy office equipment or heater and air conditioning fans.
•Avoid talking before the other person is finished speaking. When you both talk at the same time, only one person’s voice comes through.
•Do not use your speaker to make announcements over a loudspeaker paging system connected to your telephone system.
•When talking, always face your telephone and stay within two feet of it.
•Place your telephone at least six inches (15 cm) away from the edge of your desk.
•If you have difficulty hearing the other party, try increasing the speaker volume. If you have background noise, mute the microphone when the party at the other end is speaking and turning it on when you speak. If the difficulty persists, lift your handset to continue the conversation.
•In conference rooms, a conference phone is recommended, since the built-in speaker on a standard telephones are designed for individual use.