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CRM ⇄ Marketing

Apollo.io to Marketo integration — real-time, two-way sync

Keep Apollo.io 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 Apollo.io and Marketo

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

Apollo.io 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 Accounts, People (database records), Sequences, Deals (Opportunities) in Apollo.io with Programs and Program Members, Smart Campaigns, Leads, Companies in Marketo field by field, in real time, and in both directions. You decide which system owns which fields — Apollo.io 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 Land sequence enrollment status and outcomes in a warehouse for outbound performance reporting.
  • 02 Deduplicate contacts across Apollo and the CRM by syncing on email as the match key.
  • 03 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.
  • 04 Load purchase or product-usage records into Custom Objects linked to Leads so nurture campaigns branch on behavior mastered in another system.

Common sync patterns

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

New leads or responders captured in Marketo flow into Apollo.io 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.

Where Marketo captures engagement: activity lands on the record

Opens, clicks, form fills, event attendance, or ad responses recorded in Marketo post back to the contact or account in Apollo.io, so reps see interest before they reach out.

What you can sync between Apollo.io 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.

Apollo.io objects Marketo objects How this pairing syncs
Sequences Outreach cadences (emailer campaigns in the API); enrollment status is read to track which contacts are being worked. 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. Sequences is specific to Apollo.io and Static Lists to Marketo — each maps to any object or custom field on the other side.
Deals (Opportunities) Pipeline records that can be read and written to keep Apollo aligned with the CRM of record. Programs and Program Members Marketing programs read via /rest/v1/programs.json; program membership and member status managed via /rest/v1/leads/programs/{programId}.json and the program status endpoint for acquisition and attribution reporting. Deals (Opportunities) is specific to Apollo.io and Programs and Program Members to Marketo — each maps to any object or custom field on the other side.
Tasks and calls Rep activity records synced for activity reporting and coaching workflows. Smart Campaigns Automation flows read via /rest/v1/campaigns.json and run against a set of Leads by requesting a trigger campaign with POST /rest/v1/campaigns/{id}/trigger.json, so downstream logic can push Leads into a Marketo flow. Tasks and calls is specific to Apollo.io and Smart Campaigns to Marketo — each maps to any object or custom field on the other side.
Custom fields Account- and contact-level custom attributes mapped field-by-field in a sync. 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. Custom fields is specific to Apollo.io and Leads to Marketo — each maps to any object or custom field on the other side.
Contacts People saved to your Apollo account, synced with emails, phone numbers, and enrichment fields. 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. Contacts is specific to Apollo.io and Companies to Marketo — each maps to any object or custom field on the other side.
Accounts Company records with firmographic attributes, matched to CRM accounts during sync. 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. Accounts is specific to Apollo.io and Opportunities and Opportunity Roles to Marketo — each maps to any object or custom field on the other side.

How changes propagate between Apollo.io 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.

Apollo.io Marketo Interval-based propagation

DetectionStacksync polls Apollo.io for changes on an incremental schedule, reading only records changed since the previous pass. Polling on updated-at timestamps.

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

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

Rate-limit considerations

  • Apollo.io: Rate limits and enrichment credits vary by plan; bulk endpoints are throttled separately from single-record calls.
  • 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 Apollo.io ⇄ Marketo

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

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

Real-time

Two-way sync

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

No-code + pro-code

Workflow automation

Trigger automated workflows whenever Apollo.io 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 Apollo.io or Marketo record.

Observability

Monitoring

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

Trading partners

EDI

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

How the Apollo.io and Marketo connectors work

Apollo.io

Integration surface
REST API
Authentication
API key (passed in request headers); master keys unlock account-wide endpoints
Change detection
Polling on updated-at timestamps; webhook callbacks exist only for delivering asynchronous enrichment results, not as a general change-event stream
Capabilities
read · write
Rate limits
Rate limits and enrichment credits vary by plan; bulk endpoints are throttled separately from single-record calls

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 Apollo.io 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 Apollo.io 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
    Apollo.io connected
    Marketo connected
    OAuth 2.0
    SSH tunnel
    SSL certificate
    VPC peering
  2. 02

    Choose tables

    Pick the Apollo.io 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 · Apollo.io ⇄ 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
    Apollo.io Marketo
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
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FAQ

Apollo.io 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 368 integrations available for Apollo.io and Marketo.

Popular · 8 of 368
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