Zendesk to Intercom migration checklist: what to do in Zendesk, in Intercom and on cut-over day

The checklist at a glance

1. 1.Connect Zendesk with an admin who can see every ticket and Guide article.
2. 2.Recover any suspended tickets you want to keep.
3. 3.Switch off customer email notifications in Intercom for the run.
4. 4.Add a ‘Created via API’ exception to live Intercom workflows, or turn them off.
5. 5.Allow the attachment file types your Zendesk history holds.
6. 6.Create teammates, teams and ticket types in Intercom.
7. 7.Decide: conversations or tickets.
8. 8.Run a free Sample and check it in Intercom.
9. 9.Full migration, Delta runs, switch channels, last Delta.

In Zendesk before you start

• Connect with an admin who can see every ticket and Guide article. DataGrine only reads Zendesk: any request that would change it is blocked before it is sent.
• Recover suspended tickets you want to keep. They are not part of the ticket list, so a migration does not see them.
• Choose the history. Filters such as a created date range, status or tags decide which tickets a run reads. Leaving out spam and test tickets keeps the count down.
• List what you will rebuild. Triggers, automations, macros, views and SLA policies are settings, not records, and are set up again in Intercom. Write the list now, not on go-live day.
• Keep working. Your team carries on in Zendesk during the Full migration; Delta runs bring across what changed afterwards.

Want a copy of the data as well? See how to export tickets from Zendesk.

In Intercom before you start

• Switch off customer email notifications for the run. Intercom’s migration guidance says notifications on email conversations go out to the customer unless you are not live or suppress all email notifications. DataGrine does not change this for you.
• Workflows. Intercom advises an exception for ‘Created via API’ in the trigger rules of workflows that act on conversations, or turning them off during the migration.
• Fin and ratings. Pause Fin over email and conversation rating requests for the run.
• Attachment file types. Under Workspace > Security > Attachments, turn on ‘Allow leads and users to send other file types’ and add the extensions in your Zendesk history, such as docx, xlsx, csv or zip. Intercom’s defaults are gif, jpeg, jpg, mov, mp4, pdf, png, txt, heic, oga, ogg, dng and mp3; executables and password-protected archives can never be allowed.
• Teammates, teams and ticket types. Create them first: Intercom’s API cannot create teammates or teams, and the mapping can only choose what exists.

Conversations or tickets: decide once

You choose, per migration, whether Zendesk tickets land as Intercom conversations or as tickets of a type you pick. Both start as a conversation carrying the thread; Ticket then converts it, with its own attributes and states. Public comments are written as replies and private comments as internal notes, each with its original date and author.

• State last. Open or closed is written after the replies and the assignment, because each of those reopens a conversation.
• Team, then teammate. The team is assigned first and the mapped teammate second, so Intercom’s round-robin does not replace the teammate you chose.
• Long descriptions. An Intercom ticket description holds at most 32,766 characters. A longer one is cut there and named as a Vendor limit; the full text stays in the first message.

Decide before the Sample: the mapping locks for the whole migration once a run completes, a completed Sample included, or once a Full starts. A failed or cancelled Sample locks nothing. To change a locked mapping, clone the migration. More in Intercom tickets vs conversations.

Users, organisations and duplicates

• Users become contacts, matched on email or external ID, never on name or phone, so two people who share a name are never merged.
• No email and no external ID? The contact gets a stable ID from the source, so a later run finds it again instead of creating a second one.
• Archived in Intercom? A matching archived contact is unarchived and updated, not created again.
• Organisations become companies. Each company’s ID field receives the Zendesk organisation ID unless you choose another field, so a re-run updates it rather than duplicating it.

The details are in avoiding duplicate contacts in an Intercom migration.

Run a Sample and what to check

The Sample is free: 20, 100, 500 or 1,000 tickets (100 by default), with the users and organisations they use, uncounted. A Guide sample takes one category branch and up to 10 articles. Sample records are real records in Intercom, and the Full migration recognises them instead of creating them twice. Open your hardest tickets and check:

• Threads are whole and in order, with the right author on each reply, and private comments are internal notes.
• Attachments are there, and none were refused for their file type.
• Assignment, state and ticket attributes match the mapping.
• No customer received an email, and no workflow acted on a migrated conversation.

To run the Sample again, roll it back and run it again. In Intercom a rollback archives contacts rather than deleting them, deletes conversations one by one and redacts replies added to a conversation that already existed.

Cut-over day

1. 1.Run the Full migration while your team keeps working in Zendesk.
2. 2.Run a Delta near cut-over. It brings what changed since the last completed run: new tickets, changes, and only the replies Intercom has not seen. A migration includes up to five.
3. 3.Switch your channels to Intercom: email forwarding, the Messenger and anything else that creates tickets.
4. 4.Run a last Delta for anything that arrived in between.
5. 5.Check the [Reconciliation report](/reconciliation-report), which names every record not in Intercom with a reason, then switch notifications and workflows back on.

Plan the dates first: a migration stays active for 10 days from its first completed run, and a completed Sample counts. When you are ready, start on the Zendesk to Intercom migration page.

Sources

• Intercom Help - Historical data migration to Intercom
• Intercom Help - Control how attachments are used
• Intercom Help - Import your Zendesk ticket, user and organization data

Vendor facts checked against these pages on 8 November 2026. Vendors change their products; if something here has moved, tell us and we will correct it.