Switch email platforms without getting banned

1. Prove where the list came from

Keep signup source, consent wording, timestamps and any double opt-in evidence you have. Remove purchased, scraped or uncertain contacts. A provider may ask for proof, and a clean explanation is easier before an import than after an account review.

2. Import suppressions before active contacts

Move unsubscribes, complaints, hard bounces and other do-not-send records first. That prevents a newly imported campaign from contacting people who already opted out elsewhere. Preserve the reason and date where the export provides them.

3. Authenticate the sending domain

SPF

Confirm the provider's permitted sending infrastructure without creating multiple conflicting SPF records.

DKIM

Add the provider's signing records and verify them before the first customer send.

DMARC

Start with a policy and reporting setup you understand. Review alignment reports before tightening enforcement.

4. Rebuild and test the essentials

Test signup, welcome, cart, purchase and unsubscribe paths with internal addresses. Confirm sender identity, links, personalisation, suppression behaviour and the handoff from the ecommerce platform.

5. Warm up deliberately

Begin with recent, engaged and clearly consented subscribers. Increase volume as delivery, bounce and complaint signals remain healthy. Avoid changing platform, domain, list composition and campaign volume at the same moment.

Why the warning is real

The MailerLite ledger contains 145 records. A conservative text scan found 15 excerpts involving termination, suspension, disabling, blocking or bans. Klaviyo's 155-record ledger contains 9 comparable excerpts. These counts do not predict what will happen to a prepared account, but they show why compliance work belongs before import day.

Source: operator-supplied MailerLite and Klaviyo evidence ledgers. Keyword counts checked 2026-07-22.