What is “TAM” on a Fax Machine or Phone?

Last Update: August 9th, 2021


In the context of fax machines and phones, ‘TAM’ stands for ‘telephone answering machine.’

A TAM can be a feature on a fax machine equipped with an answering machine.

It can also be a switching box that decides if a call is a fax or voice call and route it to the appropriate device.

The UK and some commonwealth countries call a physical answering machine is a “TAM.” Wikipedia has more on physical answering machines. The rest of this article details a “TAM” where there is a fax machine involved.


A phone line with more than one answering type – such as a fax machine and an answering machine – uses a TAM.

When a phone line rings, a TAM checks the call to see if the call is a voice or fax call. Once it has decided, it routes the call to the appropriate device.

A TAM does not work with voicemail. Once the TAM has answered the phone line, it is not able to transfer the call back to a voicemail system. It can only transfer the call to a physical answering machine.

TAM on a fax machine

Some fax machines have a ‘TAM’ feature. The TAM tests a ringing phone line to see if the call is a fax or voice call.

If the call has the beeping of a fax tone it routs it to the fax.

If there is no fax tone, the TAM routes the call to the answering machine.

TAM as a standalone unit

A TAM can act as a standalone unit that sits ahead of a fax machine and answering machine.

Standalone units have individual ports for the fax machine and answering machine. Some models may allow for modems or an extra phone line.

With a standalone unit, a best practice is to set the number of rings on the fax machine to one or two more than the TAM is set.

When the TAM receives the call, it checks whether it is a fax tone while it keeps the fax machine ringing. If the call is a fax tone, then it lets the fax machine pick up the call. Otherwise, it disconnects the fax machine.

TAM challenges

Low ring counts

Some FAX/TAM setups need the fax machine to answer after only 2 or 3 rings. For some people, this allows too little time to answer the phone.


Callers can experience a delay as the TAM answers a call to see if it is a fax or not. To someone calling the line, the time where the TAM is checking the call may sound like the call has dropped.


Voicemail does not work with a TAM. An answering machine does work with one.

When a TAM answers the phone line to check if the call is a fax or voice call, it answers the phone line. Once the TAM answers the phone line, the call can no longer route to a voicemail service.

If the TAM answers the phone call and it not a fax call, the TAM disconnects the fax machine. Once the TAM answers the phone line, there is no way to send the call back to voicemail. To the caller, it would appear that someone answered the line and then immediately hung up the phone.

Alternatives to a TAM on a fax

While a TAM can work there are easier alternatives:

  1. An online fax service. This replaces a hardware fax machine with a hosted service. It can send and receive faxes via email and the web.
  2. An extra phone line. This gives the phone and fax separate resources.
  3. A distinctive ring phone line. One phone line can have two different numbers that make different ring tones. A fax machine or modem with DRPD (distinctive ring pattern detection) can identify the ring tones and decide whether or not to answer the line.

Sources and more resources