Verify your MailerLite subscribers
MailerLite has no SimpleVerifier connector. The round trip uses a MailerLite quirk in your favour: re-importing an address that already exists updates the subscriber instead of creating a duplicate, and MailerLite says it does not add billing cost.
The workflow
- In MailerLite go to Subscribers, pick the status from the Active subscribers dropdown, and use the dropdown arrow next to the Subscriber column to select all. Click Set columns to add the fields you need (only visible columns are exported; add Groups to keep membership), then Actions > CSV file. Only account administrators can export.
- Upload the CSV on the verify page, signed in; the first 100 checks are free. The email column is found by its header or contents and every other column is kept.
- When the job finishes, download the valid, risky and invalid files. Each keeps all of your original columns.
- Create a group such as Email invalid in MailerLite.
- Go to Subscribers > Add subscribers > Import from a CSV file, upload the invalid file and map the email column. Choose the Email invalid group as the destination. The import settings include whether blank values may overwrite existing data; keep that off.
- Remove or exclude the group from your campaigns and automations. If you prefer to delete, filter the group, select all and use the delete action once you are sure.
Menu names follow MailerLite’s own help articles, checked 12 Nov 2026: export subscribers, import subscribers. Vendors rename menus, so trust what you see on screen if it differs. SimpleVerifier is not a MailerLite partner and has no MailerLite connector.
Columns to map
- Email, the identifier for a subscriber.
- Only add other columns if you mean to update them: blank cells in the file can erase existing values unless you choose not to overwrite blanks.
- Groups, if you want to keep or change group membership through the import.
What to do with risky and catch-all results
Create a Risky group instead of removing those addresses. Send your next campaign to the main list excluding Risky, then a lighter version to Risky alone, and look at the bounce and unsubscribe counts before deciding whether to keep them.
What people use it for
- Tidy a list before moving from the free plan to a paid tier priced by subscriber count.
- Check addresses collected from embedded forms and landing pages.
- Verify a list you brought over from another platform before your first MailerLite campaign.
Using the result
Each address comes back valid (the mail server confirmed the mailbox), risky (delivery could not be confirmed: a catch-all domain, a role address such as info@, or a provider that hides mailbox status) or invalid (it will bounce, or it is a throwaway address).
Full endpoint reference, error codes and an OpenAPI file are in the API docs. For lists of thousands of addresses, upload a CSV on the verify page instead.
Run your 100 free checks on one list before you switch anything
Export one list’s addresses as a CSV and upload it: the first 100 are checked free in the dashboard, no card needed. Compare the results with what you use now, then decide. Nothing in MailerLite changes until you import a file back.
Common questions
- Which plans include API access for MailerLite?
- API access comes with Pro, Business and Agency, listed on the pricing page; Starter covers CSV verification only. A key on a plan without API access gets a 402 that says so. Each key can make 120 calls a minute.
- Will a re-import cost me extra subscribers in MailerLite?
- MailerLite says re-importing an existing address updates that subscriber and does not add to billing. Check the import summary to confirm the counts match what you expected.
- Can I use the MailerLite API instead?
- You could script it with both APIs yourself. We do not publish a MailerLite connector or script, so this page covers the CSV route.