The move itself is the easy part
Exporting contacts and importing them elsewhere takes very little time. What takes time and attention is everything attached to them.
What has to move with the list
Consent records. Who subscribed, when, and how. This is the part most likely to be lost and the part you most want to keep — it is the evidence that everyone on your list agreed to be there.
Unsubscribes and complaints. These absolutely must transfer. Emailing someone who unsubscribed on the old platform, because that record did not come across, is the most avoidable and most damaging migration mistake there is.
Engagement history. So you can still tell an active subscriber from a dormant one and prune sensibly. Some platforms export this properly and some do not.
Segments and tags. Usually need rebuilding by hand.
Automations. Never transfer. Every sequence has to be rebuilt on the new platform — which is a reasonable moment to rewrite them, since most are older than they should be.
The deliverability risk
Your sending reputation is partly tied to the platform you send from. Moving means the new provider's systems have no history with your list.
Do not send to the whole list on day one from the new platform. Start with your most engaged contacts, in batches, over a week or two. Good engagement early establishes the pattern; a large send to a mixed list on day one can land you in spam and undo the value of the move.
Redo the authentication
SPF and DKIM records point at your current sender. After migrating, they need updating for the new one, or your mail fails authentication and lands in spam.
This is the single most common post-migration failure, and it is silent — everything looks fine from your side.
Whether to move at all
Good reasons: the current platform cannot do sequences, the billing has become disproportionate for the list size, or it is not in your name.
Weak reasons: someone recommended a different one, or the interface is not to your taste. Migration always costs more attention than expected, and the gain has to justify it.
If the account is not in your name, that is on its own sufficient reason to move.
After the move
Send yourself a test to two or three different mail providers and confirm inbox placement before running anything real.
Getting it scoped
Which platform you are on, whether you can export, and how many sequences exist. Those three answers cover it.
Frequently asked questions
What must transfer when I migrate a list?
Consent records, unsubscribes and complaints above all. Emailing someone who had unsubscribed on the old platform is the most avoidable and most damaging migration mistake.
Will migrating hurt my deliverability?
It can if you send to everyone on day one. Start with your most engaged contacts in batches over a week or two so the new platform establishes a good pattern with your list.
What is the most common post-migration failure?
Forgetting to update SPF and DKIM records for the new sender. Mail then fails authentication and lands in spam, and it is silent — everything looks fine from your side.
Do my automations move across?
No. Sequences always have to be rebuilt on the new platform. That is a reasonable moment to rewrite them, since most are older than they should be.