Skip to content
Business productivity

Microsoft 365 to Slack integration — real-time, two-way sync

Keep Microsoft 365 and Slack 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 Microsoft 365 and Slack

Stop re-entering the same information in Microsoft 365 and Slack: 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 Teams, Planner & To Do Tasks, Users, Groups in Microsoft 365 with Messages, Threads, Users, User groups in Slack 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 employee records from an HR system into Entra ID users and group memberships.
  • Mirror calendar events into scheduling or CRM tools so meetings appear on customer timelines.
  • Post CRM record changes into deal or account channels so the team sees updates without opening the CRM
  • Sync the Slack user directory with the HRIS or identity provider to keep memberships and profiles current

Where Slack is where the team documents or plans: keep its data fed

Information that originates in Microsoft 365 stays current in Slack instead of going stale after a one-time paste.

Handoffs between teams

When work started in one tool continues in the other, the shared fields travel with it automatically.

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.

What you can sync between Microsoft 365 and Slack

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.

Microsoft 365 objects Slack objects
Calendar Events Events synced with scheduling tools and CRMs for meeting visibility. User groups Handles like @support that map to teams in external systems.
Contacts Personal and org contacts kept consistent with CRM contact records. Files Uploads attached to messages, retrievable for archiving.
OneDrive Files (driveItems) File and folder metadata synced for document workflows and audits. Reactions Emoji responses that can drive workflows, such as approving a synced record.
SharePoint Sites & Lists List items read and written like lightweight database tables. Channels Conversations (public, private, DMs) that messages are read from and posted to.
Teams Team and membership data provisioned from upstream systems. Messages Keyed by channel and timestamp; posted via chat.postMessage and read via history methods.
Planner & To Do Tasks Task items synced with project and work-management tools. Threads Replies grouped under a parent message timestamp, preserved when archiving conversations.
What ships with Microsoft 365 ⇄ Slack

Connect Microsoft 365 and Slack for flexible, real-time data sync.

Real-time sync, workflow automation, event queues, EDI, and monitoring, for every Microsoft 365–Slack connection.

Real-time

Two-way sync

Changes in Microsoft 365 or Slack instantly reflect in both systems. No stale data, no manual imports.

No-code + pro-code

Workflow automation

Trigger automated workflows whenever Microsoft 365 or Slack 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 Microsoft 365 or Slack record.

Observability

Monitoring

Track your Microsoft 365 ⇄ Slack sync health, view errors, and replay failed events in one click.

Trading partners

EDI

Transform legacy EDI complexity into simple database interactions between Microsoft 365 and Slack.

How the Microsoft 365 and Slack connectors work

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

Slack

Integration surface
Web API (HTTP RPC-style methods) plus the Events API
Authentication
OAuth 2.0 with bot or user tokens and granular scopes
Change detection
Events API webhooks, delivered over HTTP callbacks or Socket Mode
Capabilities
read · write · webhooks
Rate limits
Per-method rate limit tiers; message posting is additionally limited per channel
How it works

How to connect Microsoft 365 to Slack — 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.

  1. 01

    Connect your apps

    Authenticate Microsoft 365 and Slack with each platform's native method — OAuth, API keys, or service accounts — plus secure options like SSH tunneling, IP whitelisting, and VPC peering.

    • OAuth 2.0
    • SSH tunnel
    • VPC peering
    Microsoft 365 connected
    Slack connected
    OAuth 2.0
    SSH tunnel
    SSL certificate
    VPC peering
  2. 02

    Choose tables

    Pick the Microsoft 365 and Slack 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.

    • Standard objects
    • Custom objects
    • Auto-schema
    objects · Microsoft 365 ⇄ Slack
    Customers 12,480
    Sales Orders 8,213
    Invoices 5,902
    Items 1,344
  3. 03

    Map fields

    Fields map automatically even when names and types differ. Stacksync handles transformation and type casting for you, zero configuration required.

    • Auto-map
    • Type casting
    • Transforms
    Microsoft 365 Slack
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
Try interactive demo
FAQ

Microsoft 365 and Slack integration FAQ

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.

Learn more about security
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:

OAuth 2 SSH Tunnelling SSL certificates IP Whitelisting VPN gateway VPC peering and more

Related integrations

Every pair below is a real-time, two-way sync. Search all 386 integrations available for Microsoft 365 and Slack.

Popular · 8 of 386
All Microsoft 365 integrations All Slack integrations Browse all integrations
Coworkers laughing in front of a laptop in a casual office setting

Your last integration took months.
Your next one takes a prompt.

Book a demo Tour the platform on your own