Companies / Master Inbox / Slack
Does Master Inbox use Slack?
Yes
We hold strong evidence for this.
- The company names it in its own subprocessor list, a statement that this vendor handles its customers' data.
How we know
About Master Inbox
Master Inbox puts replies from sequencers, LinkedIn, website forms, ads, calls and SMS into one inbox, routed to the right rep who can reply, call or book in one place while the CRM updates. It serves sales teams, sales leaders, SDR managers and RevOps.
Summarized from its homepage on 12 Nov 2026.
What else Master Inbox uses
Master Inbox has evidence for 13 vendors. The strongest:
Cloudflare
Google
Hetzner
HubSpot
OpenAI
Paddle
Pipedrive
Postmark
Twilio
Other companies using Slack
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- Every company and vendor, with its public source
- 100 API calls a month, plus MCP and the Chrome extension
- Work email only. No card, no sales call