Migration guide: from Smartlead
Switch from Smartlead with a controlled campaign transfer.
Plan a controlled move from Smartlead. We first verify your source API access and the records available, then define what can be transferred and what must be reconnected or rebuilt. Start with one campaign before moving the rest.
Before you switch
Check these in Smartlead first.
- Create or locate a Smartlead API key you are authorized to use.
- Choose the campaigns and leads you want to import first.
- Document inbox-to-campaign allocation for the parallel cutover.
- Review suppression and block-list coverage before previewing the import.
- Note current sending schedules and limits for a conservative launch.
MailSequence provides CSV exports and a documented read API for supported resources, so data portability is part of the operating model.
Step by step
The migration, in eight controlled steps.
Audit current setup
List active campaigns, inboxes, daily limits, warmup status, domains, suppression lists, and lead lists.
Choose your first campaign
Start with one stable campaign. Move the rest after you verify the result.
Verify source access
Use your own Smartlead API key for a read-only compatibility check before creating anything.
Review the transfer scope
Confirm which campaigns, sequence content, leads, and block-list records the current source API exposes, then transfer only the supported records.
Connect business inboxes
Bring Google Workspace or Microsoft 365 inboxes through OAuth, or purchase configured business inboxes in-product.
Set conservative limits
Preserve or reduce sending limits during the transition.
Enable warmup and health monitoring
Don't push newly connected inboxes into full volume immediately.
Launch small
Send a controlled batch, watch replies and bounces, then scale.
First campaign cutover
Verify first. Cut over carefully.
Switchers from Smartlead can get hands-on help checking source compatibility, reviewing transferred records, reconnecting inboxes, checking suppression data, enabling warmup, and setting conservative limits before the first launch.
Launch safety checklist
[ ] Source API key ready[ ] Active campaigns audited
[ ] Source compatibility checked
[ ] Suppression data confirmed
[ ] Sending limits documented
[ ] Domains reviewed
[ ] Google/Microsoft inbox access confirmed
[ ] First campaign selected
[ ] Warmup plan created
[ ] Reply workflow owner assigned
FAQ
Frequently asked questions
Should I pause Smartlead before migrating?
Keep the source subscription and campaign available during review, but avoid sending the same recipient from both systems. Use a controlled audience for the MailSequence pilot.
How long does the first campaign take to move?
Timing varies with source API compatibility, available records, inbox connection, DNS readiness, warmup, and review. We confirm the work after the compatibility check.
Will my suppression list be respected?
Existing MailSequence suppressions are never cleared by a transfer. Before cutover, verify which source block-list and unsubscribe records were available and confirm the resulting MailSequence suppression list.
Do I lose my warmup progress?
Inbox reputation stays with the mailbox and domain. Keep limits conservative during the transition and use MailSequence warmup to establish a steady ramp.
What if it doesn't work out?
Export supported data through CSV and the documented read API, then choose the operating system that fits. Subscription, mailbox, domain, provider, and migration effort still need to be included in the decision.
Move one campaign this week.
Keep Smartlead running, verify one campaign can be transferred safely, and let the resulting workflow make the decision.