Migrate from MailerLite to Sendtim

1. Export from MailerLite

Export subscribers per group if you are keeping your group structure, and include every custom field column. Then export the statuses you are *not* going to mail — they are the important half.

• Active subscribers, with all custom fields.
• Unsubscribed, bounced and spam complaints — these become suppressions in Sendtim, never contacts.
• Unconfirmed subscribers, if you used double opt-in. They never confirmed, so they do not come across as subscribers; treat them as a separate re-permission problem or leave them behind.
• The HTML of the campaigns you want to rebuild, and a written outline of each automation: trigger, delay, condition, email.

2. Suppressions go in first

Load unsubscribed, bounced and complained addresses into Sendtim’s suppression list before you import a single subscriber. From then on an import cannot undo them — suppressed addresses are skipped whatever a later file says.

Bounced addresses deserve the same treatment as unsubscribes here. MailerLite stopped sending to them for a reason, and a migration is exactly the moment a stale address gets a second chance it should not get. Re-mailing a list of known hard bounces on a new sending path is how a first campaign ends up in spam.

3. Import the subscribers

1. 1Go to Contacts → Import and upload the file. Up to 200 MB, processed in the background, so a large list does not tie up the browser.
2. 2Check the mapping. MailerLite’s name is frequently one field holding a full name — map it to first name and clean it up later, or split the column in your spreadsheet before uploading.
3. 3Give each custom field column a custom property key. It becomes a merge tag of the same name: plan is {{plan}} in an email.
4. 4Pick the list these subscribers join under Options, one import per group.
5. 5Tick the consent box only for groups where you hold real opt-in, then start the import and read the rejected count.

MailerLite’s {$name} becomes {{first_name}}, and {$email} becomes {{email}}. The full list is in Personalize emails with merge tags. A tag that does not match a field renders as nothing rather than as raw text, so send yourself a test before the real send.

4. Rebuild emails and automations

Rebuild in the Sendtim editor rather than pasting exported HTML: MailerLite’s export carries its own wrapper and tracked links, and those links keep pointing at MailerLite after you have left.

Automations have to be rebuilt by hand whichever platform you leave — the trigger, the waits and the branches move, but the people currently part-way through a flow do not. Decide per automation whether to let MailerLite finish for those already inside it, or to accept a gap.

Walk through every rebuilt automation from its real trigger before a contact does. A welcome sequence that quietly fails is the one you discover last.

5. Redirect the signups

MailerLite’s embedded forms and landing pages keep working after you stop sending, which is the trap: new subscribers pile up somewhere you no longer mail. Replace them before the cutover, not after.

Sendtim offers hosted and embeddable forms, a Zapier connection, and a plain HTTP endpoint for your own code:

curl -X POST https://sendtim.com/api/v1/contacts \
  -H "Authorization: Bearer $SENDTIM_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "email": "ada@example.com",
    "firstName": "Ada",
    "listIds": ["YOUR_LIST_ID"],
    "consentGiven": true,
    "consentSource": "api"
  }'

6. Cut over

• Verify your sending domain in Sendtim and publish SPF, DKIM and DMARC before the first send. Leave MailerLite’s records in place until it has gone quiet.
• Send first to the people who opened something in the last month, then widen over a week or two.
• One owner per email type, switched over on the same day. Never send the same email from both platforms.
• Watch hard bounces and complaints against your MailerLite baseline for a fortnight.

The reasoning is in Switch email platforms without losing deliverability.