What a fax transmission report proves — and what it does not
It proves a machine at that number answered and accepted a given number of pages. It does not prove who read them, or that the right document was sent.
A transmission report is the receipt a fax leaves behind. It is also the single most misunderstood document in the whole business: people treat it as proof of delivery to a person, and it is proof of a handshake between two machines. The difference is usually irrelevant and occasionally decides a dispute.
What is actually on it
- The number dialled, exactly as it was dialled. Not the name of the organisation — the digits.
- The far end's identifier, the string that machine announces about itself. Often a number, sometimes a company name, sometimes nothing at all.
- The page count that was accepted. Not the count you sent — the count the receiving machine confirmed. When those differ, that is the interesting line.
- Duration and speed. A slow line negotiates down, and a long duration for few pages usually means a poor connection rather than a long document.
- The result, and where it failed if it did.
- A timestamp, in a stated time zone.
What it proves
That at the moment stated, a fax-capable machine answered at that number, negotiated a session, and acknowledged receiving a specific number of pages. That acknowledgement is not a courtesy: the receiving machine confirms each page at the protocol level after it has it. This is why fax persisted in regulated work long after email was better in every other way — email's read receipt is optional and forgeable, and this is neither.
What it does not prove
- That a person saw it. The pages may be in an output tray in an empty room, or in a memory buffer of a machine that has been out of toner since Friday.
- That you sent the right document. The report counts pages; it does not know what is on them. Keep the sent copy — a fax service stores it with the record, which is the point of having one.
- That the number belongs to who you think. Numbers get reassigned. The report confirms the digits you dialled, and a transposed digit produces a perfectly clean report from a stranger's machine.
- That it was legible. A fax is a scan of a scan. A page can arrive complete and unreadable, and the report will say the page arrived.
The partial-page case
If the report shows fewer pages accepted than you sent, the fax did not arrive — it half-arrived, and the far end printed what it got. Resend the whole document rather than the missing pages: the recipient has no way of knowing your second fax continues the first.
Keeping it so it is still worth something later
A report is evidence only for as long as you can produce it, in a form nobody has to take your word for. In practice that means: stored with the document it belongs to, timestamped by something other than your own filing, and retrievable by somebody who is not you.
That is the whole argument for a fax service over a machine in the corner. The machine prints the report onto the same roll of paper as everything else and then somebody files it. A service keeps the report, the document and the delivery status as one record — see the audit trail a fax leaves and how long to keep faxes.
When there is no report
No report means the call never completed, and it is not the same as a failure to deliver — it usually means the line rang out or was busy. That is a retry, not an incident. Why a fax failed covers each cause and which ones are worth retrying by hand.