Migrate from Iterable to Mailchimp

Iterable user profiles map directly to Mailchimp contacts. The dataId and email fields are the primary identifiers; we use email as the Mailchimp contact key to avoid duplicates during import. Custom profile fields in Iterable (beyond email, first name, last name) map to Mailchimp merge fields (FNAME, LNAME, PHONE, and custom MERGE1-MERGE8 depending on plan tier). Iterable's field limit of 8,000 unique fields means large deployments may need field consolidation before mapping to Mailchimp's constrained merge field schema. We flag any Iterable field with no Mailchimp equivalent and recommend a tag taxonomy or external data store for data that cannot fit in merge fields.

Iterable lists map to Mailchimp audiences. Each Iterable list becomes a separate Mailchimp audience so that existing segmentation logic and list-based Journey triggers can be mapped. Mailchimp allows a contact to belong to multiple audiences, which mirrors Iterable's list membership model. We export list names, list IDs, and the full user-to-list membership mapping from Iterable and create corresponding audiences in Mailchimp before importing contacts. Note that Mailchimp's Essentials plan is limited to 3 audiences and Standard to 5; Enterprise plans allow unlimited audiences.

Iterable's channel-level subscription state (email, SMS, push, in-app) maps to Mailchimp's contact status. Email unsubscribes migrate as unsubscribed status; bounces migrate as cleaned (bounced) status; complaints migrate as complaints. SMS opt-out status does not transfer directly because Mailchimp SMS operates on a separate consent mechanism. We export the full subscription event history from Iterable and create a suppression import file for Mailchimp to prevent emailing unsubscribed or bounced contacts during and after migration.

Iterable campaigns (with channel type, send status, schedule, and template reference) map to Mailchimp campaigns at the metadata level. Campaign content (HTML, subject line, from name, preview text) is migrated as template content. We export campaign metadata but note that historical open rates, click rates, and delivery statistics are best-effort because Mailchimp recalculates engagement metrics from the moment of import rather than preserving Iterable's historical reporting data.

Iterable templates (HTML email, plain text, and dynamic Handlebars-style personalization) map to Mailchimp templates. Handlebars variable syntax does not transfer directly; we convert Iterable personalization variables (e.g., {{firstName}}, {{event.ProductName}}) to Mailchimp merge field syntax (*|FNAME|*, *|MFVAL:field_name|*) during the content migration phase. Complex dynamic content blocks referencing Iterable Catalog data are flagged for manual rebuild because Mailchimp templates do not support Iterable's catalog content injection model.

Iterable custom events have no native Mailchimp equivalent. We handle this as a tag-based proxy: event names become Mailchimp tags applied to the relevant contact (e.g., 'purchased', 'viewed_product', 'abandoned_cart'), and event metadata is stored as tag metadata or custom field values where space permits. Behavioral event history that requires temporal ordering (e.g., the sequence of events for a user) is documented in a separate event log file that the customer's team can reference or load into an external analytics tool. This is a known trade-off when migrating from event-driven Iterable to contact-centric Mailchimp.

Iterable Journeys (multi-step, multi-channel automation paths) cannot migrate as code to Mailchimp Customer Journeys. The architectural models differ too significantly: Iterable Journeys support branching logic, multi-channel message actions (email, SMS, push, in-app), catalog content injection, and event-triggered re-entry. Mailchimp Customer Journeys support email-focused automation with trigger-based entry, simple branching, and delay actions. We deliver a written Journey inventory documenting every active Iterable Journey with its trigger conditions, message steps, branching logic, and a recommended Mailchimp Customer Journey rebuild recommendation. The customer's marketing team rebuilds Journeys post-migration.

Iterable Catalog is a structured product data store used for dynamic content insertion in messages (e.g., personalized product recommendations). Mailchimp has no native catalog object. For migrations where catalog data is central to the marketing operation, we export the catalog schemas and item records and design a flat product table (as custom fields or a separate product reference file) that can be used by the customer's development team to populate a connected e-commerce integration. If the customer uses Shopify, WooCommerce, or BigCommerce, Mailchimp's native product sync can replace Iterable's catalog functionality after migration.