What is “LINE” on a Fax Machine?

Last Update: August 9th, 2021


‘LINE’ on a fax machine is a port to connect the fax machine to a landline phone line.

The port found on its own or near an ‘EXT‘ port (used to connect a phone extension).

Image of a fax machine connected to: 1 - an extension telephone (marked "EXT" or "TEL"), 2 - a landline phone jack (marked "EXT"), and 3 - a telephone handset (marked "TEL")
The “LINE” port connects to a landline phone line. The “EXT” and “TEL” ports connect to an extension telephone. If there are three ports, the “TEL” port connects to the fax machine’s telephone handset.


Fax machines and fax modems have a ‘LINE’ port to connect the fax to a landline phone jack.

A fax machine needs a landline phone line to work.

Plugging the fax machine into the phone line is part of setting up a fax machine.

Some fax machines have line ports numerically labeled (LINE 1, LINE 2, LINE 3). These fax machines have more than one line. Connect the first line to LINE 1, and any extra lines in numerical order.

Similar Terms

Sometimes the “LINE” port is confused with ports labeled “EXT” and “TEL.”

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