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Home > Guides > Do fax machines need ink
It depends on the machine. The oldest fax machines used heat-sensitive thermal paper and needed no ink at all. Almost everything sold since the late 1990s is a plain-paper machine, which is really a printer with a fax modem inside, and it needs ink or toner exactly like any printer.
| Machine type | How it prints | Needs ink or toner? |
|---|---|---|
| Thermal fax (1980s-90s) | A heated print head darkens special heat-sensitive paper | No; but it needs thermal paper rolls, and the print fades over time |
| Inkjet fax | Sprays liquid ink onto plain paper | Yes, ink cartridges |
| Laser fax | Fuses powdered toner onto plain paper | Yes, a toner cartridge |
| Multifunction printer with fax | Whatever print engine the unit has, plus a fax modem | Yes, same as it needs for printing |
The thermal ones. Instead of ink, they used rolls of paper coated with a chemical that turns dark when heated. The print head was just a row of tiny heaters: no cartridges, no toner, nothing to replace except the paper roll. That simplicity is why thermal faxes dominated offices in the 80s and 90s.
The catch, and it was a big one: thermal print fades. Leave a thermal fax in a sunny window or a hot car and the whole page darkens into an unreadable brown sheet within months. Lawyers and accountants learned to photocopy important faxes immediately, which defeated half the convenience. If you ever find an old fax that has faded to nothing, that is thermal paper doing what thermal paper does.
Plain paper plus ink or toner, because a modern "fax machine" is a printer first. Standalone fax machines are rare now; what you buy is usually a multifunction unit that prints, scans, copies, and happens to include a fax modem. The fax side consumes the same supplies as the print side. An inkjet multifunction needs ink cartridges whether the page arrived over the phone line or from your laptop.
For receiving-heavy use, laser is the cheaper choice. Toner cartridges cost more up front but print far more pages per cartridge than ink, and toner does not dry out between uses the way inkjet cartridges do. An office that receives dozens of faxes a week will spend noticeably less on a laser machine, and the output will not smudge if it gets wet.
Yes, and this is the cost people forget when they keep a fax line. Every incoming fax is a printed page, and junk faxes print just as happily as real ones. A machine left on overnight will cheerfully print spam at 3 AM on your toner. This is one reason businesses moved to online fax services that deliver received faxes as email attachments: you only print the ones worth printing.
There is a related gotcha with inkjets: if the machine runs out of ink, most models store incoming faxes in memory instead of printing them, which sounds fine until the memory fills up and later faxes start being rejected. Check the ink on a receiving machine the same way you would on any printer you depend on.
Probably not. If you only send faxes occasionally, an online fax service replaces the machine entirely: no supplies, no phone line, no 3 AM junk-fax printing. LetterAgent's fax flow (currently in testing) takes it a step further: you describe the fax to your AI assistant, approve the quoted total, and it is sent to US and Canadian fax numbers. No machine, no ink, no toner, no thermal paper fading in a drawer somewhere.
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.
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