MIGRATION
Switch from Mailchimp to MailerLite without losing what your list knows
Your subscribers move without much trouble; what needs care is everything Mailchimp attaches to them. Export active contacts, unsubscribes and bounces, then map audiences and tags onto MailerLite groups and segments. Consent records, tag logic and automations do not travel by themselves, so rebuild and verify them before you point any form at MailerLite.
What actually transfers
MailerLite publishes a direct Mailchimp import, so a hand rolled CSV is not your only route. Through it, each Mailchimp list and tag can become its own MailerLite group, or everything can land in a single group, and custom fields are mapped automatically or by hand. Segments filtered on static fields are recreated.
Unsubscribed and unconfirmed contacts do come across, but into their own category, separate from active subscribers and unable to receive newsletters. That is the outcome you want, and it is worth knowing that a plain CSV import behaves differently: addresses already unsubscribed, bounced, unconfirmed or marked as spam fail to import at all. Your first acceptance test is the count of active subscribers against the export. If your list sits in Kit rather than Mailchimp, the Kit to MailerLite migration inventory covers the same import from the other side.
What breaks along the way
Start with the good news, because the usual advice gets it wrong: the Mailchimp export does carry your opt-in evidence. Opt-in and confirmation timestamps and IP addresses are columns in the export, and so are marketing permissions when the audience has the GDPR fields turned on. What you must do is keep that file: it is your proof of permission, and it is not something the new platform displays back to you.
What genuinely does not survive is engagement and behaviour. Opens, clicks, purchase history and the signup source of each contact are not in the export at all, so any segment built on them has to be rebuilt from new data once sending resumes. Segments filtered on behaviour, ecommerce or activity are not imported either. Forms, landing pages, templates and automations are rebuilds rather than imports.
Object by object: what comes across
| Object | Comes across | What to watch |
|---|---|---|
| Active subscribers | Yes, through the Mailchimp import tool or a CSV | The count after import is the first thing to check against the export. |
| Unsubscribes and cleaned contacts | Yes, as their own category | They arrive separated from active subscribers and cannot be mailed. On a plain CSV import they fail instead. |
| Opt-in evidence | Yes, in the export | Opt-in and confirmation timestamps and IP addresses are in the Mailchimp export. Keep the file: it is the proof, and it is not a field MailerLite displays. |
| Audiences and tags | Yes, as groups | Each list and tag can become its own group, or everything can go into one group. |
| Custom fields | Yes, mapped | Mapped automatically or by hand during the import. |
| Static segments | Yes, recreated | Only segments filtered on static fields. |
| Behaviour and ecommerce segments | No | Rebuilt by hand in MailerLite. |
| Forms and landing pages | No | Recreated in MailerLite's editor. |
| Email templates | No | Recreated in MailerLite's editor. |
| Automations | No | Rebuilt from scratch or from a MailerLite template. |
| Opens, clicks and purchase history | No | Not in the Mailchimp export at all. |
Read from each provider's own export and import documentation, listed under the table. We have not run this migration on a paid pair of accounts, so nothing here is a test result. Anything a provider does not document, we leave out rather than guess.
What the Mailchimp export gives you
- One ZIP holding separate CSV files for subscribed, non-subscribed, unsubscribed and cleaned contacts
- Audience fields, email address and subscription status
- Opt-in evidence: OPTIN_TIME, OPTIN_IP, CONFIRM_TIME and CONFIRM_IP
- Marketing permissions, when the audience has GDPR fields enabled
- Tags and profile notes
- Member rating, contact identifiers and the date the profile last changed
What it leaves behind
- Opens, clicks and other email engagement
- Purchase history and predicted demographics
- The signup source of each contact
- The full record of profile updates
Source: the official export documentation (read the official export help page).
What the MailerLite import accepts
- A direct Mailchimp import tool, so a CSV is not the only route
- Each Mailchimp list and tag turned into its own group, or everything into a single group
- Custom fields mapped automatically or by hand
- Segments built on static fields, which are recreated
What it refuses or rebuilds
- Unsubscribed and unconfirmed contacts land in their own category and cannot be sent newsletters
- On a plain CSV import, addresses already unsubscribed, bounced, unconfirmed or marked as spam fail to import
- Segments built on behaviour, ecommerce or activity conditions are not imported
- Forms, landing pages, templates and automations are rebuilt, not imported
Source: the official import documentation, plus the second official page (read the official Mailchimp migration guide and the import help page).
How the objects map
Mailchimp and MailerLite name things differently, so write the mapping before importing. A Mailchimp audience becomes a MailerLite group; if you ran several audiences, each becomes its own group or a field you can segment on. Tags map to groups or segments depending on how you used them: static labels become groups, behaviour-based tags become segment rules. Merge fields become MailerLite custom fields, match them by type so dates stay dates (the MailerLite review covers what moves in and out of the account, and which features sit behind the paid tiers). Interest groups collapse into groups or fields. Anything with no equivalent, note it as a manual rebuild rather than letting it disappear silently during import. Once the group count is settled, the MailerLite plans by subscriber count show which tier your imported list lands on.
Test before you cut over
Import into a single test group first and check it against your inventory: subscriber totals, suppressions applied, fields intact, groups populated. Then rebuild one automation, send a seed campaign, and walk a real signup through the form to confirm the person lands in the right group and starts the right sequence. Only when a full journey works end to end do you switch forms and integrations to MailerLite. On cost, both bill by active subscribers, so price the same list on each first: free plan, paid from $13/mo versus free plan, paid from $12/mo. Keep the old account read-only for a billing cycle as your rollback.
Questions people also ask
Do unsubscribes carry over automatically?
No. A standard contact export gives you active subscribers; you have to export unsubscribed and bounced addresses separately and import them into MailerLite as suppressions, or the new account will mail people who already opted out.
Will my automations keep running during the move?
No. Automations do not transfer, and any contact currently inside a Mailchimp journey stops when you migrate them. Rebuild each automation in MailerLite and decide whether in-flight contacts finish in the old account or re-enter cleanly in the new one.
Do my consent records survive the move?
The evidence does, in the export file: opt-in and confirmation timestamps and IP addresses are columns in a Mailchimp export, and marketing permissions come across when the audience has GDPR fields enabled. Keep that file as your record. The new platform does not display it back to you.
Have you run this migration yourselves?
No. Everything on this page is read from Mailchimp's export documentation and MailerLite's import and migration guides, both linked above. We have not moved a paid account between the two, so nothing here is presented as a test result.