Skip to content
Communications ⇄ CRM

Gmail to Kustomer integration — real-time, two-way sync

Keep Gmail and Kustomer 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 Gmail and Kustomer

Keep Kustomer and Gmail working from the same contacts, and log every call, message, and meeting back on the record, in real time and in both directions.

Kustomer holds the people the business talks to: the contacts, their phone numbers and email addresses, and which rep owns the relationship. Gmail is where the talking happens, whether that is calls, texts, email, or meetings. The two depend on the same people, and when the contact list in one drifts from the other, outreach goes to stale numbers and the record of what was said never makes it back to the account.

Stacksync syncs Notes, Customers, Conversations, Messages in Kustomer with Attachments, History, Messages, Threads in Gmail field by field, in real time, and in both directions. Current contact details flow out to Gmail so it can reach the right person, and the calls, messages, and meetings Gmail produces flow back onto the matching record in Kustomer. You decide which system owns which fields, and conflicts resolve by rules you set.

Common use cases

  • 01 Push order and shipment records from commerce systems into Kustomer custom objects so agents answer order-status questions without switching tools
  • 02 Mirror conversations and satisfaction data into a warehouse for support analytics and agent performance reporting
  • 03 Create Drafts in a rep's mailbox from CRM templates and sequences, keeping sends authentic to the sender's address and signature.
  • 04 Read Attachments and message metadata into a warehouse or document store for retention, discovery, and compliance reporting.

Common sync patterns

Calls, messages, and meetings on the record

Activity handled in Gmail appears on the matching contact and account in Kustomer, so the next person sees the full history without leaving the CRM.

Where Gmail sends at scale: delivery and reply status back on the contact

Sends, bounces, opens, and replies from Gmail update fields on the contact in Kustomer, so lead status reflects what actually reached the person.

One contact list, opt-outs included

A number, address, or unsubscribe recorded in either system updates the other, so no one calls a disconnected line or messages someone who opted out.

What you can sync between Gmail and Kustomer

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.

Gmail objects Kustomer objects How this pairing syncs
Messages Individual emails with headers, body, and label state; read out to a CRM or warehouse for activity logging, and sent or modified two-way from sales tools. Messages Individual messages within conversations support full-thread replication. Same entity on both sides — records pair one-to-one and field-level changes reconcile in both directions.
Threads Conversation groupings that keep replies together; synced so a CRM timeline or support desk shows the full exchange, not isolated messages. Notes Internal annotations carry context alongside synced conversations. Threads is specific to Gmail and Notes to Kustomer — each maps to any object or custom field on the other side.
Labels User and system labels (INBOX, SENT, custom); applied and removed via sync to mirror pipeline stages or triage states from an external system. Customers The central record whose timeline aggregates every interaction; external attributes sync onto it. Labels is specific to Gmail and Customers to Kustomer — each maps to any object or custom field on the other side.
Drafts Unsent messages; created and updated from templates or sequence tools so reps review before sending from their own mailbox. Conversations Support threads across channels sync outward for analytics and CRM context. Drafts is specific to Gmail and Conversations to Kustomer — each maps to any object or custom field on the other side.
Attachments File payloads referenced by message part; read out to storage or a document system for archival and compliance workflows. Companies Organization records group customers and map to CRM accounts. Attachments is specific to Gmail and Companies to Kustomer — each maps to any object or custom field on the other side.
History The incremental change log keyed by historyId; used for efficient delta sync so only mailbox changes since the last cursor are fetched. Custom Objects (Klasses) Structured external records such as orders and subscriptions synced in to appear on the customer timeline. History is specific to Gmail and Custom Objects (Klasses) to Kustomer — each maps to any object or custom field on the other side.

How changes propagate between Gmail and Kustomer

Each direction of the sync is driven by what the source system can signal and what the destination accepts — detection, delivery, and expected latency below.

Gmail Kustomer Sub-second propagation

DetectionGmail notifies Stacksync of record changes through webhook events. Incremental sync via users.history.list from a stored historyId cursor, plus real-time push notifications through Google Cloud Pub/Sub watch on the.

DeliveryEach detected change is written to Kustomer through its API, with automatic retries and rate-limit backoff.

Kustomer Gmail Sub-second propagation

DetectionKustomer notifies Stacksync of record changes through webhook events. Outbound webhooks on record events, plus polling for backfill.

DeliveryEach detected change is written to Gmail through its API, with automatic retries and rate-limit backoff.

Rate-limit considerations

  • Gmail: Quota is measured in units per user per second (e.g. messages.list = 5 units, messages.send = 100 units) against a 250 quota-unit/user/second limit and a daily project cap; exceeding limits returns 429 with exponential backoff expected.
  • Kustomer: Subject to the platform's API rate limits.
What ships with Gmail ⇄ Kustomer

Connect Gmail and Kustomer for flexible, real-time data sync.

Real-time sync, workflow automation, event queues, EDI, and monitoring, for every Gmail–Kustomer connection.

Real-time

Two-way sync

Changes in Gmail or Kustomer instantly reflect in both systems. No stale data, no manual imports.

No-code + pro-code

Workflow automation

Trigger automated workflows whenever Gmail or Kustomer 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 Gmail or Kustomer record.

Observability

Monitoring

Track your Gmail ⇄ Kustomer sync health, view errors, and replay failed events in one click.

Trading partners

EDI

Transform legacy EDI complexity into simple database interactions between Gmail and Kustomer.

How the Gmail and Kustomer connectors work

Gmail

Integration surface
Gmail API (REST, v1)
Authentication
OAuth 2.0 via Google — user-authorized consent with granular scopes (gmail.readonly, gmail.modify, gmail.send, gmail.labels); restricted scopes require Google's app verification for production use
Change detection
Incremental sync via users.history.list from a stored historyId cursor, plus real-time push notifications through Google Cloud Pub/Sub watch on the mailbox (watch must be renewed at least every 7 days)
Capabilities
read · write · webhooks
Rate limits
Quota is measured in units per user per second (e.g. messages.list = 5 units, messages.send = 100 units) against a 250 quota-unit/user/second limit and a daily project cap; exceeding limits returns 429 with exponential backoff expected.

Kustomer

Integration surface
REST API
Authentication
API key used as a bearer token, scoped by role
Change detection
Outbound webhooks on record events, plus polling for backfill
Capabilities
read · write · webhooks
Rate limits
Subject to the platform's API rate limits
How it works

How to connect Gmail to Kustomer — 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 Gmail and Kustomer 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
    Gmail connected
    Kustomer connected
    OAuth 2.0
    SSH tunnel
    SSL certificate
    VPC peering
  2. 02

    Choose tables

    Pick the Gmail and Kustomer 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 · Gmail ⇄ Kustomer
    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
    Gmail Kustomer
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
Try interactive demo
FAQ

Gmail and Kustomer integration FAQ

SECURITY

Security teams trust 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
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 269 integrations available for Gmail and Kustomer.

Popular · 7 of 269
All Gmail integrations All Kustomer 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