Migrate from Assembly Neos to Mailchimp

Neos contacts map 1:1 to Mailchimp contacts inside a target audience. The primary company is stored as a Mailchimp merge field (COMPANY). Contacts without a valid email address are flagged and excluded from migration — Mailchimp requires an email address for every subscriber.

Neos company name maps to a Mailchimp CONTACTMANY merge field. Neos allows N:N contact-to-company links — the primary company becomes the merge field value, and additional companies are stored as a secondary merge field (ALT_COMPANY) or as tags on the contact.

Neos contact phone number maps directly to the Mailchimp PHONE contact field. If the contact has multiple phone types in Neos (office, mobile, direct), the primary phone number migrates first; additional numbers are appended as a text merge field. Phone numbers are normalized to a standard format during migration, stripping extraneous characters such as parentheses or dashes, ensuring consistent data in Mailchimp's phone merge field.

Neos stores structured address fields. Mailchimp uses six dedicated address merge fields. If Neos uses a single address string rather than parsed components, FlitStack AI parses it into the correct merge field slots — ADDR1 gets street, CITY gets city, STATE gets state, ZIP gets postal code, COUNTRY gets country name.

Neos contact email maps directly to the Mailchimp subscriber email address, which is the unique identifier for each contact. If a Mailchimp contact with the same email already exists in the target audience, FlitStack AI updates the existing record rather than creating a duplicate.

Neos matters have no Mailchimp equivalent. FlitStack AI applies a Mailchimp tag per matter (e.g., tag: 'Case: Smith-v-Jones') and stores the matter name and status as merge fields on the associated contacts. This preserves the case relationship without requiring a custom Mailchimp object.

The Neos user or attorney assigned to a contact migrates as two merge fields on the contact record: ATTORNEY_NAME and ATTORNEY_EMAIL. This preserves firm relationship data without creating Mailchimp users — only contacts migrate, not internal firm user accounts. If an attorney has multiple email addresses in Neos, the primary email is used for ATTORNEY_EMAIL, and any secondary addresses are stored as a text merge field for completeness.

Mailchimp does not store original creation timestamps on contacts. FlitStack AI creates a MERGE10-style custom merge field (ORIGINAL_CREATE_DATE) on the audience to preserve the Neos contact creation date for reporting continuity. This date field is useful for analyzing contact age, segmenting by onboarding period, and maintaining historical data integrity after the migration.

The Neos internal contact ID is stored as a custom merge field (NEOS_CONTACT_ID) for traceability, delta-run de-duplication, and rollback identification. This field is used internally and is typically hidden from Mailchimp audience views. It also enables you to re-sync contacts in future delta runs without creating duplicates, and facilitates audit comparisons between Neos and Mailchimp records.

Neos documents, e-filed items, PDFs, and case file attachments have no Mailchimp equivalent. These are not migrated. If documents need to be accessible in Mailchimp, they must be hosted externally and linked from within email campaigns. This approach ensures that document links remain current and can be updated independently of the Mailchimp audience.

Neos time entries, invoices, trust ledger entries, and billing records have no Mailchimp equivalent. FlitStack does not migrate these objects. Firms needing billing history accessible alongside Mailchimp contacts should maintain Neos access for read-only reference. This allows finance teams to continue reviewing client billing details without interfering with the marketing-focused Mailchimp environment.

Neos task templates, checklists, milestone triggers, and workflow automations have no Mailchimp equivalent. These must be rebuilt in Mailchimp's Customer Journey builder or a third-party automation tool after contacts land in the audience. Your marketing team can design email sequences, autoresponders, and event-driven campaigns to replicate the workflow logic originally configured in Neos.