Migrate from MailerLite

How-to guide

For:: Publishers and marketers, Workspace admins
Needs permission:: subscribers:import
In the app:: Import contacts

To migrate from MailerLite, you connect ReputeCast to your MailerLite account with an API token and import each group into a ReputeCast list, with its subscribers’ fields, opt-in dates and statuses. ReputeCast only reads from the MailerLite API; nothing changes in MailerLite.

Before you begin

You need the subscribers:import permission (Owner, Admin and Editor have it).
Create a MailerLite API token. In MailerLite, open Integrations, choose MailerLite API and click Generate new token. Copy it at once: MailerLite shows it only once. A token belongs to the user who created it and stops working if that user is removed from the account. Source: MailerLite developers, Getting started (checked October 2026).
The importer reads the MailerLite API at connect.mailerlite.com. MailerLite Classic accounts use an older API, which the importer doesn’t support; export a CSV from them and import the file instead.
Read how a migration carries consent if this is your first import.

Import your MailerLite groups

Open Import contacts and choose MailerLite. The wizard links to MailerLite’s API page if you still need a token.
Paste the token and select Connect. The wizard lists your groups with their subscribed, unsubscribed, cleaned (bounced) and pending counts.
Tick the groups to import and pick the ReputeCast list each one goes into. Keep pulling suppressions from your sending providers on, then continue to field mapping.
Map the fields. email is required; MailerLite fields such as name and last_name are matched by name and sample values, and new custom fields are created for the rest.
On the consent step, check what each status becomes (see the next section). The opt-in date and IP from MailerLite are kept as consent evidence unless you choose Re-permission everyone first.
Run the preview and start the import.

What moves from MailerLite

Groups become the ReputeCast lists you chose. Subscribers who aren’t in any group aren’t read: add them to a group in MailerLite before you import, or export them as a CSV.
Fields become contact fields.
Opt-in evidence: the opt-in date and IP address are stored as consent evidence, and the subscription date becomes the contact’s creation date.

MailerLite status	Becomes in ReputeCast
`active`	Subscribed · confirmed, with the opt-in date and IP as evidence (or pending, or Skip)
`unconfirmed`	Subscribed · pending, with a re-permission email (or Skip)
`bounced`	Suppressed · hard bounce, all streams (locked)
`junk`	Suppressed · complaint, all streams (locked)
`unsubscribed`, or any other status	Suppressed · unsubscribed: no Broadcasts or Automations, System mail allowed (locked)

New suppressions keep the reason from MailerLite, such as “cleaned in MailerLite” for a bounced subscriber, and are pushed to every connected sending provider that keeps its own suppression list.

What stays in MailerLite

Campaigns and their reports, automations, segments, forms, landing pages and templates are not imported. Rebuild them with segments, automations, signup forms and the composer.

Rate limits

The MailerLite API allows 120 requests a minute and answers 429 Too Many Attempts above it, with a Retry-After header. Source: MailerLite developers, Getting started (checked October 2026). ReputeCast reads 1,000 subscribers per request, one request at a time, waits for Retry-After when MailerLite asks it to, and pauses the import when the source keeps refusing:

Setting	Default	How to change
Largest CSV or XLSX file	100 MB and 500,000 rows (XLSX reads the first sheet)	Fixed
Source API rate limit (429)	Up to 5 retries, each after the source's Retry-After (2 s when absent, at most 60 s); then the import pauses and resumes by itself after 1 minute	Resume now, or Slow down to 3 req/s on the paused import
Source server or network errors	Up to 5 retries, after 1, 2, 4, 8 and 16 s	Fixed

Slow down to 3 req/s sends at most 3 requests a second, which is still above MailerLite’s average of 2 a second, so a large account may still pause now and then. Each pause resumes by itself.

Check that it worked

The summary shows how many contacts were imported, merged, suppressed, left pending and skipped, and how many each list now has. Download full report · CSV lists every row with what happened to it.
Open Audience, then Suppression list: bounced, junk and unsubscribed subscribers are there with the reason from MailerLite.

Troubleshooting

“MailerLite rejected the API key”: the token was deleted, or the user who created it left the account. Generate a new token and paste it.
A group is missing: the importer lists every group of the account the token belongs to. Check that you created the token in the right MailerLite account.
Subscribers missing from the import: they are in no group, or their status made them a suppression. Unconfirmed subscribers come in as pending and get no marketing mail until they confirm.
“MailerLite is rate-limiting us (429), import paused”: another integration is using the same account’s limit. Wait for the automatic resume, or select Resume now.