Typical Fax Error Rates

Our sending faxing system has a very healthly success rate of over 96%.    Receive success is lower as we have less control of the transmission path. Unfortunately, many endpoints are poorly designed fax over IP (FoIP) endpoints.

When faxes fail, it is typically a single fax source that says “We can’t send a fax to you”

Failed Faxes? – The process we need from you

  1. What is the time and date of the fax? What was the remote telephone number? How many pages? We will return reasons for the failure and next steps.
  2. We provide a sign-on to a third party efax system.  If faxes fail using this independent system, the problem is with the remote user.
  3. Sending fax does not send a properly formated 10 digit Caller ID. Needs to be fixed by customer’s telecom vendor.
  4.  Otherwise, the issue is escalated to our tier 3 support on a ticket with results from #1 and #2. We will work the ticket.

Typical reasons for failure

  • Too many pages such as a 60 page fax.  It’s a paper jam or the next fax user canceled your hour duration fax job.  
  • The fax machine, fax server and/or VoIP analog Terminal Adapter (ATA) needs to be power cycled. An ATA example would be a Comcast Arris adapter.
  • Path problem – “Problem in the middle” cured in a few hours or by us issuing you a second fax number for the send fax failing remote user.

Observations from our industry peers say a 6% error rate (send and receive combined) is typical

Fax transmission is an analog technology. It’s modem tones transmitted over a phone line at around 2100 hz. In the old days of analog lines, what fax is based on, we saw error rates of 6%. Like making a copy of an (analog)  cassette tape, analog fax tones can be compressed and re-transmitted that yield literally a poor sounding copy of the original fax transmission.  Today, in the day of voice over IP VoIP and without our services,  we see as much as a 20% error rate. Beyond our data, below is third party evidence.

” no one will sign off on it but you are looking at 5 – 7%”  – industry expert. We can play the name of this person and company privately.

… googling the phrase https://www.google.com/search?&q=typical+facsimile+error+rate


“When attempting to send real-time faxes over an IP network that is operating under normal conditions, a success rate of 80% is reasonable for single-page faxes. ”



“Traditional analog faxing has roughly a 5% failure rate; e-faxing has a slightly higher failure rate around 5-8% due to the additional steps necessary with a fax server. ”



“Fax over internet, FoIP, had formerly been unable to achieve a transmission success rate of more than 85%