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Yes, you can send a fax from your computer by preparing the document as a file and sending it through an online fax service, with no fax machine or phone line needed on your side. LetterAgent's fax service is in testing for US and Canadian numbers, so use it as a testing option, not a guaranteed send today.
An online fax service sits between your computer and the recipient's fax machine. You upload or share a document file, give the recipient's fax number, and the service converts the file and sends it as a fax. The recipient sees a normal fax, whether their machine is a physical device on a desk or an online inbox. Your computer never needs a modem, a phone line, or a fax machine of its own. All it needs is the file and an internet connection.
This is different from the older way of faxing from a computer, which used a fax modem and a phone line plugged into the machine. That route still exists on some older computers, but it is rare now, and most people who say they "fax from a computer" mean the online route. If your computer has no modem, that is fine: the online route does not need one.
| Route | What you need | When it fits |
|---|---|---|
| Online fax service | A document file and the recipient's fax number | Most cases, any modern computer |
| Fax modem | A modem, a phone line, and fax software | Older setups that already have the hardware |
| Email to fax gateway | An email account and a gateway address | Offices that already use a gateway service |
PDF is the best choice for most faxes from a computer, because it locks page order, fonts, and layout in place. A word processor file can shift when it is opened on another machine, and a set of loose images can arrive out of order. Before sending, open the PDF yourself and check every page: are the pages upright, complete, and in order, with no blank pages slipped in? A quick check here prevents the most common fax failure, which is a missing or upside-down page that the recipient only notices after you have hung up.
For scanned paper, scan at a setting that keeps text sharp but does not make the file huge. Very large files can fail or take a long time to send, while very small scans can turn small print into unreadable marks. If your document has colour charts or photos, remember that fax transmission is black and white: colour will be converted, and pale colours may vanish. For colour-critical pages, consider sending a copy by email as well, and use the fax only for the signed or official version.
A cover sheet is not always required, but it is good practice for a fax from a computer, because it tells the recipient who the fax is for, how many pages to expect, and how to reach you if a page is missing. Include your name, the recipient's name, the total page count including the cover sheet, and a phone number or email address. That page count matters: if the recipient gets fewer pages than the cover sheet promises, they know at once that something went wrong.
Keep the cover sheet short. A long cover note wastes the recipient's time and can confuse a busy office about which page is the real document. One short paragraph stating the purpose of the fax is enough.
Enter the full fax number with its area code, and double-check each digit before sending. A fax sent to the wrong number cannot be pulled back, and it may land on a stranger's machine. Confirm that the number is a fax number, not a voice line, and call the recipient first if you are unsure. Also confirm whether the recipient expects a fax from you: some offices only accept faxes at certain hours, or only from known senders, and an unexpected fax can sit unread.
Common failures from a computer include a busy signal at the recipient's end, a file that is too large, and a document that was never converted cleanly. If a send fails, check the file first, then the number, then try again. Keep the confirmation or error message the service gives you, and note the date and time of the send. For an important fax, call the recipient after sending and ask them to confirm the page count and legibility.
LetterAgent's fax service is available in testing. The flow is a per-fax quote with the page count verified, then you approve the exact total, then a one-time Stripe payment, then the fax is sent. It works for US and Canadian fax numbers only, and it does not accept inbound faxes. Because fax is still in testing, with activation in progress, do not rely on it for a same-day deadline until you have confirmed that your fax went through. For an urgent fax, keep a backup route ready.
To use it from your computer, prepare your document as a clean PDF first, then describe the fax to your AI assistant, including the recipient's fax number. Approve the exact quoted total before anything is sent, and confirm receipt with the recipient if the fax matters.
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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