Fax survives in government because of one property nothing else has: the transmission report is third-party evidence the document arrived. Remote CSID, page count, duration, timestamp. An email produces none of that, and a certified-mail green card takes weeks.
[object Object] · [object Object] · [object Object] · [object Object] · [object Object] · [object Object] · [object Object] · [object Object].| Provider | Type | Per page | Monthly min | Note |
|---|---|---|---|---|
| Telnyx Programmable Fax | api | $0.01 | — | Lowest per-page rate found and no monthly minimum. The usual migration target after Twilio shut down. |
| Phaxio (Sinch) | api | $0.07 | — | Long-standing developer API. Roughly ten times Telnyx per page at volume. |
| ClickSend Fax | api | $0.05 | — | API plus dashboard and email-to-fax. Free trial credit. |
| mFax (Documo) | api | $0.05 | $25.00 | Subscription shape — cheaper above roughly 300 pages/month, worse below it. Was Twilio's named migration partner. |
| FaxZero (free tier) | webform | free | — | ⚠️ NOT FOR EVIDENTIARY SENDS. Web form behind a CAPTCHA — no API. Places an advertisement on the cover page, and the transmission report is theirs, not yours. |
FaxZero is genuinely free and genuinely useful for sending a form to a doctor's office. It is disqualified for anything evidentiary for two reasons that have nothing to do with quality: it prints an advertisement on the cover page of your document, and the transmission report is theirs, not yours — you cannot produce it. Use it for errands, never for a records request or a filing.
DISCONTINUED FOR ALL ACCOUNTS 17 December 2021 after fraudulent traffic made it unsupportable. API calls fail outright. It is still the first thing people reach for, which is why it is recorded here rather than omitted. Discontinued 2021-12-17.
Busy is the normal outcome for a government fax line, not the exception — they are frequently single-line and in use. Retrying a busy line in ten seconds just burns a page charge, so the waits escalate.
| Conversion | Lossy? | Note |
|---|---|---|
md-to-pdf |
no | The composer emits markdown; agencies want PDF. |
docx-to-pdf |
no | |
pdf-to-docx |
LOSSY | ⚠️ Lossy. Layout and any scanned text are approximated. Never round-trip a filing through it. |
img-to-pdf |
no | Phone photographs of a paper order. |
pdf-shrink |
LOSSY | ⚠️ Downsamples images. Fine for an email attachment cap; NOT for an exhibit where a stamp or signature must stay legible. |
raster-to-svg |
LOSSY | Vectoriser. |
pdf-ocr |
no | Adds a text layer without altering the image — makes a scanned release searchable. |
The lossy ones matter: never round-trip a filing through PDF→DOCX, and never shrink a PDF where a stamp or a signature has to stay legible in an exhibit.
Engineering and regulatory orientation, not legal advice. The FCC obligations named here are real and enforced; confirm your own position with counsel before carrying a single call to a phone number.