LetterAgent
Mail physical letters by just asking your AI assistant.
Home > Guides > Fax polling explained
Fax polling is the reverse of a normal fax. Instead of pushing a document to someone, your machine calls theirs and pulls a document they have loaded for pickup. Companies once used it like a self-serve document shelf: leave a price list in the machine overnight, and callers could fetch it any time. It still works on machines that support it.
Two machines and one phone call. The owner of the document loads it into their fax machine and switches on polling mode, which tells the machine to wait for incoming retrieval calls. You, the retriever, dial their number with your own machine's polling feature enabled. When the machines connect, instead of your machine sending, theirs transmits the stored document to you. Many machines let the owner protect the document with a polling ID or passcode, so only callers who know the code can pull it. Some support scheduled polling: your machine dials at 2 a.m., when long-distance rates were once cheapest, and fetches the document unattended.
Polling predates the web, and it solved a problem the web later erased: how do you distribute a document to many people without staffing a phone? A supplier could load the week's price list on Friday evening, and every dealer could poll it over the weekend. News services used it for bulletins. Field offices retrieved forms from headquarters without anyone at headquarters lifting a finger. The clever part was the asymmetry: one person did the work once, and any number of callers fetched the result. It was the fax era's version of a download link.
Both machines must support polling, and both ends must set it up correctly: the document has to be loaded and polling enabled on one side, and the retrieval feature switched on at the other. A mistyped polling passcode means a failed call and no document. The biggest modern catch is that most online fax services never implemented polling. It was designed for machine-to-machine calls over phone lines, and services built around email-to-fax or app-based sending usually skip it. LetterAgent cannot receive faxes at all, so polling is not possible through LetterAgent: there is no inbound document to retrieve.
| Method | Direction | Best for |
|---|---|---|
| Normal fax | Push: you send to them | One-off documents to a specific recipient |
| Fax polling | Pull: you fetch from them | Documents many callers need, retrieved on their own schedule |
| Fax broadcasting | Push to many numbers at once | The same document sent out to a whole list |
Rarely, but it survives in corners where fax machines never left: some pharmacies, auto-parts distributors, and government offices still poll forms from counterparties running old equipment. If someone asks you to poll their machine, confirm the polling passcode and the exact time window the document will be loaded; a machine that is not in polling mode will simply answer with a normal receive tone and leave you with a failed call.
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