What is “TEL” on a Fax Machine?
Last Update: August 9th, 2021
Definition
“TEL” on a fax machine or fax modem can be:
- A port to connect a telephone handset to a fax to enable the fax machine as a telephone.
- A port to connect the fax to a phone jack (sometimes labeled “LINE“).
- A port to connect an extension telephone to the fax (sometimes labeled “EXT“).
- In the context of “FAX/TEL,” a switch that changes between fax, telephone, or both modes.

How to use a “TEL” port to connect a telephone handset
Some fax machines come with a telephone handset. These machines can function as both a phone and a fax.
A fax machine with a handset feature includes the handset and phone cord. To use it, connect the handset to the fax machine with the phone cord and leave the handset on the hanger.
How to use a “TEL” port to connect the fax to a phone line
If there is one port for a phone line labeled “TEL,” it is for the landline phone line.
Connect the fax machine to the landline phone line with a regular phone cord. T fax machine can now send and receive faxes.
How to use a “TEL” port to connect an extension phone
If there are two ports, one of which is labeled “TEL”…
- …and the other “EXT”: The “TEL” port is to connect the fax to the phone line and the “EXT” port for an extension telephone.
- …and the other “LINE“: The “LINE” port is for the telephone jack. The “TEL” port is to connect an extension telephone or a telephone handset (see above).
If there are three ports, one labeled “TEL” and the others “EXT” and “LINE,” the “TEL” port is for a telephone handset.
How to use the “FAX/TEL” feature
A FAX/TEL button on a fax machine sets the machine to either receive calls as a fax, telephone call, or both.
- The “FAX” setting answers a ringing phone line as a fax machine. When the phone line rings, it answers the line and expects to receive a fax.
- The “TEL” setting answers a ringing phone line as a telephone. To receive a fax, someone needs to be at the machine, answer the call, and press a button to receive the fax.
- A “Both” or “FAX/TEL” setting has the machine first answer the call as a fax. If there is no fax tone beeping on the line, it switches to ringing the phone. Some people calling the number may find this setting difficult, as it may sound like the call dropped.
An alternative for both a fax machine and telephone on the same line is to use a dual ring (DRPD) fax.
Similar Terms
The “TEL” port can be confused with the “EXT” (for an extension telephone) and “LINE” (to connect to a landline phone line) ports.
Sources and more resources
- Xerox Support Forum – Fax – LINE and EXT – A discussion on the differences between a LINE and EXT port on a Xerox fax machine.
- Epson Support – Connecting a Telephone or Answering Machine – Instructions on how to connect a telephone or answering machine to a fax machine using the EXT port.
- Canon Fax-B840/B820/B822 User’s Guide – page 7 – a Canon fax machine user manual that describes the use of each phone port.
- Epson WF-2750 User’s Guide – page 24 – an Epson fax machine user manual that shows where the “EXT” and “LINE” ports are.
- Xerox Work Center 7120 User Guide – page 24 – A Xerox MFP user manual that shows the location of phone ports on the device. Includes a line for “TEL” as well as 3 different “LINE” ports.