Partner spotlight: Master Inbox
Master Inbox is a unified inbox that combines social and email conversations for sales teams. See how it connects to OutboundSync in beta.
Jason Ma
Masterinbox → HubSpot
Masterinbox + HubSpot integration
Master Inbox pulls every outbound inbox into one place. OutboundSync puts what happens there on the HubSpot Contact: messages in and out, labels, and prospect list changes.
BetaOne-way syncEmail and social
Masterinbox + HubSpot at a glance
Yes, Master Inbox integrates with HubSpot through OutboundSync. Outgoing and incoming messages from the email and social inboxes connected to Master Inbox, plus label changes and prospect list changes, are written to the matching HubSpot Contact as timeline events. Tools that connect through Master Inbox, such as Expandi, Salesflow, and PlusVibe, reach HubSpot the same way.
| Status | Beta (Masterinbox setup is guided by the OutboundSync team) |
|---|---|
| Channels | Email and social |
| Direction | One-way, Masterinbox → HubSpot |
| HubSpot records | Contacts, with optional Company association |
| Block lists | Not available for this pairing |
| Masterinbox plan | Needs webhook access |
| Setup | Self-serve: install the app from the HubSpot App Marketplace; Masterinbox source set up with our team |
Master Inbox is a hub: teams connect many sending accounts and tools, then work every conversation from one place. That makes it a natural single point for CRM sync. Instead of wiring each tool to HubSpot, you connect Master Inbox once and OutboundSync logs its message stream on the right Contacts.
Labels are how Master Inbox users mark intent, and prospect lists are how they organize follow-up. Both changes arrive as timeline events, so a HubSpot workflow can respond when a conversation is labeled interested or moved to a new list, with no manual update in the CRM.
What syncs from Masterinbox to HubSpot
Every event below arrives in near-real time and lands on the matched HubSpot record. Pick the ones you want per source.
| Event | Channel | Where it lands in HubSpot |
|---|---|---|
| Message sent— Outgoing messages from connected accounts, logged as email sends | Email timeline event on the Contact | |
| Email received— Incoming messages on connected email accounts | Email timeline event on the Contact, with the reply text | |
| Social message received— Incoming messages on connected social accounts | Social | Social timeline event plus a Communications record with the message text |
| Label changed | Timeline event plus OutboundSync Contact properties | |
| Prospect list changed | Timeline event plus OutboundSync Contact properties |
Event names come from the Masterinbox webhooks OutboundSync receives. See the Masterinbox event reference.
What teams do with Masterinbox + HubSpot
Sync many tools at once
Connect Master Inbox once and log conversations from every inbox behind it in HubSpot.
Workflow on labels
Trigger HubSpot workflows when a Master Inbox label changes to interested or not now.
Follow list moves
Prospect list changes show where each conversation sits in your follow-up process.
Ways to connect Masterinbox and HubSpot
The options teams weigh before they commit a production sync.
| Option | What it does | Trade-off |
|---|---|---|
| Zapier, Make, or n8nCompare integration platforms | Catch Masterinbox webhooks and write each event to HubSpot with a workflow you build. | Every event type, retry, and field change is a workflow you maintain, billed per task or step. |
| Custom buildBuild vs buy | Write your own service against the Masterinbox and HubSpot APIs. | You own matching, deduplication, API limits, and every upstream schema change. |
| OutboundSync | Pre-built email and social activity sync into HubSpot Contacts. | Self-serve setup, searchable event logs, and support from the team that maintains the connector. |
How to set up Masterinbox + HubSpot
Step 1: Install the HubSpot app
A Super Admin installs OutboundSync from the HubSpot App Marketplace and approves the OAuth scopes.
Step 2: Connect Masterinbox
The OutboundSync team creates your Masterinbox source with you and points Masterinbox's webhooks at it.
Step 3: Choose events and properties
Pick which Masterinbox events to log as timeline events and which OutboundSync Contact properties to write.
Step 4: Send a test event
Trigger one Masterinbox event and confirm it on a real Contact.
Step 5: Go live
Turn on the source and start building HubSpot workflows, active lists, and custom reports on real Masterinbox data.
Plan requirements
Masterinbox plan
Needs webhook access
OutboundSync receives Masterinbox activity through webhooks. Confirm your Masterinbox plan includes webhook access, or ask us to check during setup.
HubSpot
OutboundSync works on every HubSpot tier with no feature gating. Your tier decides what you can build on the synced data.
Which HubSpot tier you need
| Tier | Fit | What it adds |
|---|---|---|
| Free | Reply and CRM management for up to 1,000 contacts. |
|
| Starter | CRM hygiene with minimal automation, no reporting. |
|
| ProfessionalMost common | Scaling CRM full automation, light reporting. |
|
| Enterprise | All-in-one CRM system of record and system of action. |
|
Related integrations and guides
Masterinbox with other CRMs
Other outbound tools for HubSpot
Millions of activities synced every month
David
Stord
Freckle
Factorial
Cerby
HygraphMasterinbox + HubSpot FAQ
What Masterinbox activity does OutboundSync sync to HubSpot?
Message sent, email received, social message received, label changed, and prospect list changed.Which HubSpot records does it write to?
OutboundSync matches or creates HubSpot Contacts. Masterinbox events land as email timeline event on the Contact; or email timeline event on the Contact, with the reply text; or social timeline event plus a Communications record with the message text; or timeline event plus OutboundSync Contact properties. See the HubSpot data model docs for details.Is this different from tools that connect "via Master Inbox"?
Yes. This page covers the direct Master Inbox to HubSpot connection. Partner tools such as Expandi, Salesflow, and PlusVibe route through Master Inbox, and their activity arrives through this same connection.Is the integration one-way or two-way?
One-way. Activity flows from Masterinbox into HubSpot, and nothing is written back to Masterinbox.Do I need admin access to set it up?
A HubSpot Super Admin installs the OutboundSync app and keeps it authorized.Which Masterinbox plan do I need?
OutboundSync receives Masterinbox activity through webhooks. Confirm your Masterinbox plan includes webhook access, or ask us to check during setup.How is Masterinbox + HubSpot priced?
OutboundSync bills on sent messages per month. Replies, opens, clicks, and lead-category updates are not billed. Plan details are on the pricing page.Can I do this with Zapier, Make, or n8n?
Yes, for lightweight automation. Zapier, Make, and n8n are good for prototypes and simple routing, but they need ongoing maintenance and bill by task or step. OutboundSync is pre-built for outbound CRM sync, keeps searchable event logs beyond 30 days, and prices by outbound volume.What breaks first when this scales?
Data quality and reliability break first: duplicate events, retries, out-of-order webhooks, and bursts during big sends. OutboundSync handles idempotency, timing buffers, and queue recovery, and flags suspicious or mismapped payloads instead of writing them.
Masterinbox resources
Tutorials, case studies, and updates related to Masterinbox.
See Masterinbox activity in HubSpot
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