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CRM ⇄ Marketing

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

Keep Kustomer and Marketo in sync without custom scripts. Cut weeks of integration work, eliminate silent data drift, and give your team a single, reliable source of truth.

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Why teams connect Kustomer and Marketo

Keep the people you sell to and the people you market to in one shared view: Kustomer and Marketo sync contacts, accounts, and engagement in real time, in both directions.

Kustomer owns the customer relationship and the pipeline; Marketo runs the campaigns, audiences, and outreach that fill it. The two overlap on the same people and companies — a lead in one system is a subscriber, a segment member, an event registrant, or an ad audience in the other. When that overlap is bridged by CSV exports or a nightly job, sales works from lists that no longer match reality and marketing keeps targeting people whose status has already moved on.

Stacksync syncs Conversations, Messages, Companies, Custom Objects (Klasses) in Kustomer with Smart Campaigns, Leads, Companies, Opportunities and Opportunity Roles in Marketo field by field, in real time, and in both directions. You decide which system owns which fields — Kustomer can own account and opportunity status while Marketo owns engagement and campaign membership — and Stacksync keeps every copy consistent and resolves conflicts 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 Two-way sync Marketo Leads with a Postgres or warehouse table, matched on email, so RevOps queries and updates marketing profiles in SQL while marketers keep working in Marketo.
  • 04 Extract Marketo Activities (opens, clicks, form fills, Data Value Changes) through Bulk Activity Extract or Get Lead Activities into a warehouse for lead scoring and multi-touch attribution.

Common sync patterns

Segments and audiences follow the CRM

Where Marketo builds lists, segments, or ad audiences, membership tracks the fields and stage owned in Kustomer, so who receives a campaign reflects current pipeline reality instead of a stale export.

Where Marketo generates leads: hand-off without re-keying

New leads or responders captured in Marketo flow into Kustomer assigned and deduplicated, so nothing sits in a marketing list waiting for someone to export it.

New and updated people stay in step

When a contact or lead is created or edited in either system, the matching record appears or updates in the other, so campaigns reach real people and reps see who is already being marketed to.

What you can sync between Kustomer and Marketo

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.

Kustomer objects Marketo objects How this pairing syncs
Companies Organization records group customers and map to CRM accounts. Companies Company records linked to Leads via a company link field; read and upserted through /rest/v1/companies.json, typically mastered in a CRM or ERP and written into Marketo for account context. Same entity on both sides — records pair one-to-one and field-level changes reconcile in both directions. Custom fields on either side are included in the mapping.
Teams Team assignments support routing parity and reporting. Leads Core person records (called Leads/People), deduped on email address by default or a configured dedupe field; read via GET /rest/v1/leads.json with a filterType, upserted via POST /rest/v1/leads.json (action createOrUpdate/createOnly/updateOnly), bulk-imported via CSV through POST /bulk/v1/leads.json, and bulk-exported via /bulk/v1/leads/export/create.json. Teams is specific to Kustomer and Leads to Marketo — each maps to any object or custom field on the other side.
Tags Labels on conversations and customers sync for categorization and analytics. Opportunities and Opportunity Roles Revenue objects synced via /rest/v1/opportunities.json and /rest/v1/opportunities/roles.json; roles associate an opportunity with a Lead, so pipeline data can drive nurture and scoring. Tags is specific to Kustomer and Opportunities and Opportunity Roles to Marketo — each maps to any object or custom field on the other side.
Notes Internal annotations carry context alongside synced conversations. Custom Objects Auxiliary data tables described via /rest/v1/customobjects.json and read/written via /rest/v1/customobjects/{apiName}.json, linked to Leads by a dedupe/link field so campaigns branch on records like purchases or subscriptions. Notes is specific to Kustomer and Custom Objects to Marketo — each maps to any object or custom field on the other side.
Customers The central record whose timeline aggregates every interaction; external attributes sync onto it. Activities and Lead Changes Engagement feed (opens, clicks, form fills, Data Value Changes) read via GET /rest/v1/activities.json using a paging token from /rest/v1/activities/pagingtoken.json (sinceDatetime), plus Get Lead Changes and Get Deleted Leads; read-only, also available via async Bulk Activity Extract. Customers is specific to Kustomer and Activities and Lead Changes to Marketo — each maps to any object or custom field on the other side.
Conversations Support threads across channels sync outward for analytics and CRM context. Static Lists Named static lists; read via /rest/v1/lists.json, with Leads added or removed via POST and DELETE on /rest/v1/lists/{listId}/leads.json to control campaign membership from lifecycle logic computed downstream. Conversations is specific to Kustomer and Static Lists to Marketo — each maps to any object or custom field on the other side.

How changes propagate between Kustomer and Marketo

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.

Kustomer Marketo 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 Marketo through its API, with automatic retries and rate-limit backoff.

Marketo Kustomer Interval-based propagation

DetectionStacksync polls Marketo for changes on an incremental schedule, reading only records changed since the previous pass. Polling: Get Lead Changes and Get Lead Activities from a paging token seeded by a sinceDatetime, plus Get Deleted Leads, or Bulk Extract filtered on.

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

Rate-limit considerations

  • Kustomer: Subject to the platform's API rate limits.
  • Marketo: Interactive calls are capped at 100 per 20 seconds (error 606) and a maximum of 10 concurrent calls (error 615) per instance, neither increasable; a default daily quota of 50,000 calls (increasable, resets midnight CST) applies. Bulk Extract shares a 500 MB/day export quota across data types with at most 2 concurrent jobs and 10 queued.
What ships with Kustomer ⇄ Marketo

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

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

Real-time

Two-way sync

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

No-code + pro-code

Workflow automation

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

Observability

Monitoring

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

Trading partners

EDI

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

How the Kustomer and Marketo connectors work

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

Marketo

Integration surface
Marketo REST API (JSON over HTTPS) for Leads, Companies, Opportunities, Custom Objects, Activities, Lists, Programs, and Campaigns, plus an asynchronous Bulk Import (leads) and Bulk Extract (leads/activities/program members/custom objects) API and an Asset REST API for emails, forms, and landing pages
Authentication
OAuth 2.0 client_credentials (2-legged): GET the Identity URL /oauth/token?grant_type=client_credentials with a Custom Service client_id and client_secret to receive an access token valid for 3600 seconds, then send it as Authorization: Bearer on each call. The instance base URL is https://{munchkinId}.mktorest.com; passing the token as an access_token query parameter is deprecated (removal July 31, 2026).
Change detection
Polling: Get Lead Changes and Get Lead Activities from a paging token seeded by a sinceDatetime, plus Get Deleted Leads, or Bulk Extract filtered on createdAt/updatedAt. Marketo's Webhooks are Smart Campaign flow-step outbound HTTP calls to a URL, not a general record-change subscription, so there is no push feed of arbitrary CRUD.
Capabilities
read · write
Rate limits
Interactive calls are capped at 100 per 20 seconds (error 606) and a maximum of 10 concurrent calls (error 615) per instance, neither increasable; a default daily quota of 50,000 calls (increasable, resets midnight CST) applies. Bulk Extract shares a 500 MB/day export quota across data types with at most 2 concurrent jobs and 10 queued.
How it works

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

    Choose tables

    Pick the Kustomer and Marketo 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 · Kustomer ⇄ Marketo
    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
    Kustomer Marketo
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
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FAQ

Kustomer and Marketo 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.

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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 378 integrations available for Kustomer and Marketo.

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