Slack Fax — Fax Alerts in a Slack Channel, Plus Sending via the API
Slack connects to Send FAX Mail two honest ways. Getting fax alerts is a real feature: connect a Slack incoming-webhook URL and every delivered, failed, and received fax posts a concise, PHI-safe message to your channel. Sending from Slack is not a native slash command from us — you drive it with a Slack workflow or a small bot that calls our REST API. We have nothing listed in the Slack App Directory, and we do not imply we do.
Plan requirement
Slack fax-status messages work on any paid plan; you self-connect the webhook at /dashboard/settings without an API key. Sending from a Slack workflow or bot uses our REST API, which is part of the Business ($79.99/mo) and Enterprise ($169.99/mo) plans. Notifications and sending are separate — turning on alerts requires no developer work.
How it works
For alerts, you create a Slack incoming webhook for a channel and paste its https://hooks.slack.com/services URL into settings. When a fax event is confirmed, our server posts a short message to that channel built from a masked number that shows only the last four digits, the status, the page count, and a dashboard link — never the document, so HIPAA tiers are safe. Delivery follows the same fax-status toggle as email notifications, and an inbound fax marked webhook-only in a number's forwarding rule suppresses the Slack ping. For sending, a Slack Workflow Builder step or a bot with a message shortcut collects a number and a file link and POSTs them to /v1/faxes, then replies with the fax id.
What you can do
- ✓Post delivered, failed, and received fax messages into a Slack channel
- ✓Include only a masked last-four number, status, page count, and a link
- ✓Self-connect the incoming webhook at /dashboard/settings, no key required
- ✓Gate alerts with the same fax-status toggle as email notifications
- ✓Send a fax from a Slack workflow or bot that calls /v1/faxes
- ✓Reply in-thread with the returned fax id for a visible trail
Setup steps
- 1Create a Slack incoming webhook for the channel that should receive alerts
- 2Paste the hooks.slack.com URL at /dashboard/settings to turn alerts on
- 3For sending, put the account on Business or Enterprise and create a key at /dashboard/developers
- 4Build a Slack workflow or bot that collects a number and a file link
- 5Have it POST the recipient and document link to /v1/faxes with your key
- 6Reply to the thread with the returned fax id so the channel shows status
Example
// Slack bot or workflow step (Node)
await fetch("https://www.sendfaxmail.com/v1/faxes", {
method: "POST",
headers: {
Authorization: "Bearer sfm_live_xxxxxxxx",
"Content-Type": "application/json",
},
body: JSON.stringify({ to: number, document_url: fileLink }),
});Slack Fax — FAQ
Yes. Connecting a Slack incoming webhook in settings is a shipped, self-serve feature: our server posts a message to your channel on every delivered, failed, and received fax. It needs no API key and no bot — that separates it from the send path, which you build yourself against our REST API.
It cannot. The message is assembled from a number masked to its last four digits, the status, the page count, and a link into the dashboard — the PDF and full number are never included. That design keeps the alert safe even on HIPAA-tier accounts, where document content must stay inside an authenticated session.
Yes. Slack alerts honor the account's fax-status toggle, and a number configured as webhook-only in its forwarding rule suppresses the Slack ping for its inbound faxes while still firing your customer webhooks. So you can route quiet numbers to systems without lighting up a human channel.
Not one we ship. There is no Send FAX Mail app in the Slack directory. To send from Slack you build a Workflow Builder step or a bot that POSTs to /v1/faxes, which requires a Business or Enterprise plan. The alert direction is native; the send direction is bring-your-own against the API.
Build with the Slack Fax
API access and webhooks are included on the Business and Enterprise plans. Create a key at /dashboard/developers and start sending.
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