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What happens to unsubscribed contacts when you switch email platforms
The risk in a platform switch is not losing contacts. It is mailing someone who opted out. An export of “all contacts” often includes them, and an import treats everyone as subscribed.
Why it goes wrong
A CSV carries an email address and a few fields. The unsubscribed flag may not be in the file. If it is, the new tool may ignore it. Bounced and complained contacts have the same problem.
What OpenContact does
A migration never makes someone mailable who was not mailable at the source.
| Source status | Result |
|---|---|
| Subscribed | Copied into the destination list |
| Unsubscribed, bounced, complained, suppressed | Not added to the list. Excluded at the destination where the tool allows it. Status updated in OpenContact |
| Never confirmed consent (for example Mailchimp pending) | Skipped |
In Mailjet, excluded contacts are blocked from campaigns. Someone who opted out of any list is excluded everywhere in tools with account-wide exclusion.
Checks before you start
- Run Check what will happen. It shows, for the first 100 contacts, how many would be copied, excluded or skipped.
- Confirm the source tool reports statuses. Mailchimp, Mailjet, Brevo, MailerLite, Klaviyo, ActiveCampaign and Kit do. For a source that does not, contacts are copied as before.
- Remember Klaviyo profiles that never subscribed but are not suppressed can still receive Klaviyo email, so they are copied.
After the switch
Connect both tools to a sync rule with suppression enabled. An unsubscribe in the new tool then reaches the old one, and the other way round, while both are connected.