Real-time
Two-way sync
Changes in Customer.io or Microsoft 365 instantly reflect in both systems. No stale data, no manual imports.
Business productivity
Customer.io to Microsoft 365 integration — real-time, two-way sync
Keep Customer.io and Microsoft 365 in sync without custom scripts. Cut weeks of integration work, eliminate silent data drift, and give your team a single, reliable source of truth.
- SOC 2 and 6 other compliance frameworks
- POC with real engineers in minutes
Adopted by fast-scaling companies moving mission-critical data in real time
Case study
Migrated from Mulesoft
Case study
Migrated from Celigo
Migrated from Heroku Connect
Migrated from Matillion
Case study
Migrated from Fivetran
Case study
Migrated from Celigo
Why teams connect Customer.io and Microsoft 365
Stop re-entering the same information in Customer.io and Microsoft 365: Stacksync keeps the records they share consistent in real time, in both directions.
Two tools in the daily stack often hold overlapping information: the same people, the same companies, or the same pieces of work, described twice. The tools do different jobs, so consolidating is not the answer; the overlap just needs to stop drifting.
Stacksync syncs Events, Segments, Campaigns, Broadcasts in Customer.io with OneDrive Files (driveItems), SharePoint Sites & Lists, Teams, Planner & To Do Tasks in Microsoft 365 in real time. You choose which records overlap, map the fields that should match, and pick a direction or let changes flow both ways. From then on, an update made in either tool is reflected in the other within seconds, without exports or copy-paste.
Because the sync is field-level, each tool keeps its own extras; only the shared data is held in agreement.
Common use cases
- Sync account-level objects and their person relationships for B2B messaging keyed to company attributes.
- Sync product usage and billing attributes from Postgres onto Customer.io people so lifecycle campaigns trigger on real product behavior.
- Keep CRM contacts and Microsoft 365 contacts aligned in both directions.
- Sync employee records from an HR system into Entra ID users and group memberships.
Where both tools track people or companies: one consistent record
Contact and company details corrected in either tool update the other, so nobody works from the old version.
Where one tool produces events: mirror them in the other
Payments, replies, messages, or tickets created in one tool can create or update matching records in the other, keeping context in one place.
Where Microsoft 365 is where the team documents or plans: keep its data fed
Information that originates in Customer.io stays current in Microsoft 365 instead of going stale after a one-time paste.
What you can sync between Customer.io and Microsoft 365
Representative objects on each side — any object or custom field can map to any target. Schemas are auto-detected; types are converted between the two systems.
| Customer.io objects | Microsoft 365 objects | |
|---|---|---|
| Events Behavioral events sent via the Track API that trigger campaigns. | OneDrive Files (driveItems) File and folder metadata synced for document workflows and audits. | |
| Segments Attribute- or event-based groups; data syncs feed the attributes segments evaluate. | SharePoint Sites & Lists List items read and written like lightweight database tables. | |
| Campaigns Automated workflows whose membership and metrics can be read via the App API. | Teams Team and membership data provisioned from upstream systems. | |
| Broadcasts One-off sends to segments or audiences, triggerable via API. | Planner & To Do Tasks Task items synced with project and work-management tools. | |
| Deliveries / Messages Per-recipient message records whose lifecycle events flow out through reporting webhooks. | Users Entra ID user accounts synced with HR and identity systems. | |
| Newsletters Recurring email sends with performance metrics available for reporting syncs. | Groups Microsoft 365 and security groups kept aligned with org structure and access rules. |
What ships with Customer.io ⇄ Microsoft 365
Connect Customer.io and Microsoft 365 for flexible, real-time data sync.
Real-time sync, workflow automation, event queues, EDI, and monitoring, for every Customer.io–Microsoft 365 connection.
No-code + pro-code
Workflow automation
Trigger automated workflows whenever Customer.io or Microsoft 365 data changes, update records, fire webhooks, or kick off sequences without brittle API scripts.
At scale
Event queues
Handle millions of events per minute without losing a single Customer.io or Microsoft 365 record.
Observability
Monitoring
Track your Customer.io ⇄ Microsoft 365 sync health, view errors, and replay failed events in one click.
Trading partners
EDI
Transform legacy EDI complexity into simple database interactions between Customer.io and Microsoft 365.
How the Customer.io and Microsoft 365 connectors work
Customer.io
- Integration surface
- REST APIs split by purpose: Track API for data ingestion, App API for campaigns, people lookups, and messages
- Authentication
- Basic auth with site ID and API key for the Track API; bearer token for the App API
- Change detection
- Reporting webhooks push message and delivery events; person attribute changes are not streamed and require source-side detection
- Capabilities
- read · write · webhooks
- Rate limits
- Subject to per-API rate limits documented by Customer.io
Microsoft 365
- Integration surface
- REST API (Microsoft Graph)
- Authentication
- OAuth 2.0 via Microsoft Entra ID, with delegated or application permissions
- Change detection
- Graph change notifications (webhooks) plus delta queries for incremental sync
- Capabilities
- read · write · webhooks
How it works
How to connect Customer.io to Microsoft 365 — three steps, no code
Configure and sync within minutes, no code. Whether you sync 50k or 100M+ records, Stacksync handles the queues, infra, and plumbing. Integrations are non-invasive and need zero setup on your systems.
- 01
Connect your apps
Authenticate Customer.io and Microsoft 365 with each platform's native method — OAuth, API keys, or service accounts — plus secure options like SSH tunneling, IP whitelisting, and VPC peering.
Customer.io
connected
Microsoft 365
connected
OAuth 2.0SSH tunnelSSL certificateVPC peering - 02
Choose tables
Pick the Customer.io and Microsoft 365 objects to sync — Stacksync auto-detects both schemas, including custom fields where the platform exposes them. Sync to existing tables, or let Stacksync create new ones with ideal data types.
objects · Customer.io ⇄ Microsoft 365Customers 12,480Sales Orders 8,213Invoices 5,902Items 1,344 - 03
Map fields
Fields map automatically even when names and types differ. Stacksync handles transformation and type casting for you, zero configuration required.
Customer.io Microsoft 365Company company_name textEmail email textAmount amount numericCreated created_at timestamp
FAQ
Customer.io and Microsoft 365 integration FAQ
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Yes. Stacksync provides a managed, real-time two-way integration between Customer.io and Microsoft 365: authenticate both systems, choose the objects to sync (such as Customer.io's Events and Segments), map fields visually, and changes propagate both ways in milliseconds — no code required.
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Stacksync pricing is usage-based and starts at $1,000/month, including the managed Customer.io and Microsoft 365 connectors, real-time two-way sync, monitoring, and support. That replaces building and maintaining a custom Customer.io–Microsoft 365 integration in-house.
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Yes — Stacksync ships production-grade connectors for both Customer.io and Microsoft 365. The connectors handle authentication, schema detection, rate limits, and retries; you configure the sync, and Stacksync operates it.
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Change detection on Customer.io: Reporting webhooks push message and delivery events; person attribute changes are not streamed and require source-side detection. On Microsoft 365: Graph change notifications (webhooks) plus delta queries for incremental sync. Each detected change propagates to the other side in milliseconds, with field-level conflict resolution and an inspectable event log.
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On the Customer.io side: Events, Segments, Campaigns, Broadcasts, plus custom fields where Customer.io exposes them. On the Microsoft 365 side: OneDrive Files (driveItems), SharePoint Sites & Lists, Teams, Planner & To Do Tasks. Stacksync auto-detects both schemas and converts types between the two systems.
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Yes. Each object mapping can be bidirectional or restricted to a single direction (both systems accept writes). Read-only mirrors, one-way pushes, and full two-way sync can be mixed in the same integration.
SECURITY
Security teams love Stacksync
As a data company, we understand the importance of keeping your data secure. Stacksync is built with security best practices to keep your data safe at every layer, and is DPF-certified for US, EU, UK and CH data transfers.
SOC 2 type II
ISO 27001
HIPAA BAA
GDPR
CCPA
CSA STAR
DPF US-EU-UK-CH
→ SECURITY WITH BENEFITS
SSO & SCIM
Let your users access Stacksync from your centralized user management systems. Works with Okta, Azure, Google SSO and more.
Alerts
Immediately get alerted about record syncing issues over email, Slack, PagerDuty and WhatsApp. Resolve issues from a centralized dashboard with retry and revert options.
Secure connection options
Securely connects to your systems with:
Related integrations
Every pair below is a real-time, two-way sync. Search all 386 integrations available for Customer.io and Microsoft 365.
Popular · 8 of 386
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Customer.io ⇄ Microsoft Teams -
Customer.io ⇄ NextGen Healthcare -
Customer.io ⇄ Orderful -
Customer.io ⇄ Resend -
Microsoft 365 ⇄ Aviato -
Microsoft 365 ⇄ eClinicalWorks -
Microsoft 365 ⇄ Full Enrich -
Microsoft 365 ⇄ Google Sheets
No integrations match .
