Know in Slack the moment a contract is signed
A signed contract usually means someone has to act: order materials, book the crew, send the welcome pack. A Slack message in the right channel makes sure they know. SignMaster sends the webhook, and Zapier, Make or n8n turns it into the message.
Updated November 5, 2026 · 2 min read
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Why not a Slack incoming webhook?
Slack's own incoming webhooks expect a message in Slack's format, with a text or blocks field. SignMaster sends its own JSON, so pointing it straight at a Slack webhook URL fails. An automation tool reads SignMaster's message and writes the Slack one.
Set it up
- 1
Pick your events
envelope.completed for wins, envelope.declined for problems to chase, envelope.expired for contracts that went quiet. Use one endpoint per channel, or one endpoint with a branch per event.
- 2
Catch the webhook
Create a Zapier Catch Hook, a Make Custom webhook or an n8n Webhook node and add its URL in Settings › Developers › Webhooks with those events ticked.
- 3
Send a test
SignMaster's test message is enough to build an alert from the title and status. Sign a real contract afterward to check the wording with real answers.
- 4
Post the message
Use Slack Send Channel Message in Zapier, Send a Message in Make, or the Slack node's message Send operation in n8n. Pick the channel and write the text using values from the webhook.
- 5
Turn it on
Publish the Zap, scenario or workflow, and watch the first real alert come through.
Messages that work
- Completed: the contract's name from data.envelope.title, who signed from data.recipients, and two or three key answers from data.fields_by_label, such as the job address and price.
- Declined: the contract's name and the signers' statuses from data.recipients, so whoever owns the customer can call the same day.
- Expired: the contract's name and the people who hadn't finished, so someone can resend it or close it out.
- Viewed: usually too noisy for a channel. If you want it at all, send it as a direct message to the person who sent the contract.
A completed alert might read: Signed: Henderson roof replacement, by Dana Ruiz. 412 Oak Street, start date March 3. Short enough to read on a phone, with enough detail that nobody has to open SignMaster to know what to do next.
Keep the channel useful
Alerts that fire on every view teach people to ignore them. Start with completed and declined only. For a busy team, route each template to its own channel: the message carries data.envelope.template_id, so a filter or a router can send roofing contracts to the roofing channel and service plans to the service team.
Questions? Answers.
Is there a SignMaster app for Slack?
No. Slack alerts run through webhooks and Zapier, Make or n8n. SignMaster also emails you the signed PDF when a contract is completed, with no setup.
Can the Slack message include the signed PDF?
It can include the link from data.signed_pdf.url, which works for 24 hours. To keep the file, save it to your storage in the same automation and post that link instead.
Can alerts go to more than one channel?
Yes. Add a Slack step per channel, or route by template or event with a filter in Zapier, a Router in Make or a Switch node in n8n.
Can I tag the salesperson who sent the contract?
The webhook doesn't name the sender, so add it yourself: put the salesperson's name in a Prepared by text box on the template, or keep a list of templates and owners in your automation.