LetterAgent
Mail physical letters by just asking your AI assistant.
Home > Guides > Fax machine memory
Yes. Most fax machines hold the scanned pages in memory until the call completes, and many keep copies longer: redial buffers, out-of-paper storage, delayed-send queues, and transaction reports all retain your pages. On a shared office machine, your documents can sit in memory long after you walk away.
It is how the machine survives a bad phone line. When you feed pages into a fax machine, it scans them into memory first, then dials. If the line is busy or the call drops mid-transmission, the machine redials and resends from memory: without that stored copy, a failed call would force you to feed every page again. This is also what powers delayed sending (scan at 5 PM, transmit at midnight for cheaper rates) and broadcasting to several numbers at once. The memory buffer is a feature, and the copies are the price of it.
| Memory location | What it holds | How long it lasts |
|---|---|---|
| Send buffer | Pages of the fax you just transmitted | Usually cleared after a successful send, but some machines keep it until the next job |
| Redial / last-transmission memory | The most recent fax, kept for one-touch resend | Until overwritten by the next fax; check the manual to clear it |
| Receive buffer | Incoming faxes stored when the machine runs out of paper or toner | Until paper is loaded and they print, sometimes for days |
| Delayed-send queue | Faxes scheduled for a later time | Until the scheduled send completes |
| Transaction journal | A log of recent activity with small thumbnails or first-page images on many models | Often the last 30 to 100 transactions |
More than most people realize. A machine in a hallway or copy room can hold your tax forms, medical records, or legal documents in its memory while the next dozen people fax after you. On many office multifunction machines, anyone can reprint the last received fax, view the transmission log, or redial the last number. If you must use a shared machine for sensitive documents, take three steps: wait for the confirmation page before leaving, look for a "clear memory" or "secure print" option in the menu, and ask whoever administers the machine how long the journal is kept. Better still, send the fax in a way that never touches shared hardware.
Not always. Some machines use volatile memory that clears when the power is cut; others use flash or battery-backed memory that survives unplugging. That is why secondhand fax machines are a known privacy risk: companies retire them with years of documents still in memory, the same way old copiers made headlines years ago. If your business decommissions a fax machine, run the manufacturer's memory-clear procedure or destroy the memory board. Donating or selling a machine without clearing it is how strangers end up reading your old faxes.
Online fax moves the copies off the machine and onto the provider's servers, which cuts both ways. On the plus side, there is no shared physical machine storing your pages where coworkers can reprint them, and you keep your own file. On the minus side, the provider necessarily handles your document, so its data handling matters: look for a stated retention policy rather than assuming copies vanish. With LetterAgent, you send a fax by asking your AI assistant: you get a per-fax quote with the page count verified, you approve the exact total, pay once through Stripe, and the fax is sent. LetterAgent covers US and Canadian fax numbers only and cannot receive inbound faxes. Faxing is currently available in testing while activation is in progress, so treat it as available in testing and never count on a fax sending the same day until the service confirms otherwise.
Ready to fax it? Fax with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is sent.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
Need help? Ask your assistant: it can check a job's status any time. If it ever can't handle something: hello@getletteragent.com