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

Keep Lemlist 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

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Why teams connect Lemlist and Microsoft 365

Stop re-entering the same information in Lemlist 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 Unsubscribes, Webhooks, Team Members, Campaigns in Lemlist with Mail Messages, Calendar Events, Contacts, OneDrive Files (driveItems) 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 replies, opens, and bounces from Lemlist into the CRM so outbound activity shows on lead and contact records
  • Push enriched leads from a warehouse or list-building workflow into Lemlist campaigns automatically
  • 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.

Where Microsoft 365 is where the team documents or plans: keep its data fed

Information that originates in Lemlist stays current in Microsoft 365 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 Lemlist 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.

Lemlist objects Microsoft 365 objects
Leads Per-campaign prospect records sync in from enrichment sources and back out with status. Calendar Events Events synced with scheduling tools and CRMs for meeting visibility.
Activities Engagement records such as opens, clicks, replies, and bounces sync to CRM timelines. Contacts Personal and org contacts kept consistent with CRM contact records.
Unsubscribes Opt-out records propagate to other outreach tools and the CRM for compliance. OneDrive Files (driveItems) File and folder metadata synced for document workflows and audits.
Webhooks Hook subscriptions define which activity events are pushed to external endpoints. SharePoint Sites & Lists List items read and written like lightweight database tables.
Team Members Sender and seat records map outreach activity to reps in other systems. Teams Team and membership data provisioned from upstream systems.
Campaigns Outreach campaigns are the container leads are pushed into from CRMs and list-building workflows. Planner & To Do Tasks Task items synced with project and work-management tools.
What ships with Lemlist ⇄ Microsoft 365

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

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

Real-time

Two-way sync

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

No-code + pro-code

Workflow automation

Trigger automated workflows whenever Lemlist 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 Lemlist or Microsoft 365 record.

Observability

Monitoring

Track your Lemlist ⇄ 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 Lemlist and Microsoft 365.

How the Lemlist and Microsoft 365 connectors work

Lemlist

Integration surface
REST API
Authentication
API key
Change detection
Webhooks on outreach activity events, plus polling
Capabilities
read · write · webhooks
Rate limits
Subject to the platform's API rate limits

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 Lemlist 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.

  1. 01

    Connect your apps

    Authenticate Lemlist 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.

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

    Choose tables

    Pick the Lemlist 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.

    • Standard objects
    • Custom objects
    • Auto-schema
    objects · Lemlist ⇄ Microsoft 365
    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
    Lemlist Microsoft 365
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
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FAQ

Lemlist and Microsoft 365 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 Lemlist and Microsoft 365.

Popular · 8 of 386
All Lemlist integrations All Microsoft 365 integrations Browse all integrations
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