Smartlead is built around running a lot of mailboxes. Teams who use it seriously tend to have 50, 150, sometimes 400, spread across dozens of domains with rotation rules tuned over months.
That shapes the migration. The leads and sequences are the small part. The mailbox estate is the migration.
Start with an estate inventory
Before anything else, export your email account list and answer four questions:
Who owns the domains? If they are in your registrar account, everything below is straightforward. If an agency or a mailbox vendor registered them, the warmed reputation is theirs and you need that conversation first.
Where did the mailboxes come from? Google Workspace, Microsoft 365, a mailbox vendor, or an SMTP provider. Mailboxes you bought from a vendor usually port fine over SMTP and IMAP; check that the vendor allows it before you commit to a date.
What is the mailbox-to-domain ratio? Smartlead estates are often built at five or more per domain. Three is the safer working ratio, and a migration is a reasonable moment to spread out.
Which mailboxes are actually producing? Most large estates have a tail of accounts that bounce more than they reply. You are about to reconnect every one of them by hand. Do not bring the dead weight.
That last point saves real time. A 200-mailbox estate frequently has 40 accounts nobody would miss.
What exports from Smartlead
| Asset | Export |
|---|---|
| Leads with custom fields | CSV, per campaign |
| Blocklist and unsubscribes | CSV, pull this first |
| Email account list | CSV, with SMTP/IMAP settings |
| Campaign analytics | CSV, per campaign |
| Master inbox threads | No export |
| Sequences | No export, copy the text |
| Rotation and sending settings | No export, document them |
The account list export is the one that makes this manageable. It gives you host, port and username per mailbox, which is what bulk connection needs.
Document the settings nobody exports
Smartlead’s value is in tuning, and none of it comes across in a file. Before you cancel, write down:
- Daily send limit per mailbox
- Ramp-up settings and current step
- Sending window and time zone per campaign
- Rotation behaviour across the estate
- Any per-mailbox custom tracking domains
- Webhook endpoints and what they fire on
Twenty minutes of screenshots now saves a fortnight of rediscovering what your limits were.
The plan
Week 1, export and prune
Pull the blocklist first, then leads, then the account list, then analytics. Copy sequences into a document.
Then prune. Decide which mailboxes come with you. Anything with a sustained bounce rate above 3% or placement problems you never solved should be retired rather than migrated, you are rebuilding the estate anyway, and bringing a damaged domain across imports the problem.
Week 2, bulk connect
Create the workspace structure. If you run clients, one workspace each, which also means client suppression lists stay separate. The agency structure piece covers the layout.
Load suppressions before any leads. Merge the Smartlead blocklist with your own do-not-contact list into one global list.
Then bulk-connect the mailboxes from your account list CSV. This is the step that takes the longest at scale, and it is why the pruning in week one matters.
Smartlead keeps sending throughout. A mailbox can hold connections to two platforms at once; you are adding a route, not switching one.
Week 3, rebuild and run in parallel
Rebuild your best campaign, set your daily limits to match what you documented, and run at 20% of volume alongside Smartlead.
Watch per-mailbox metrics rather than campaign averages. With a large estate the average hides everything, a campaign at 2% bounce can contain fifteen mailboxes at 6%.
This is also the point to add LinkedIn steps if multichannel is part of why you are moving. Smartlead is email-first, so teams running both channels usually have a second tool and a second inbox; folding them into one sequence is most of the practical gain.
Week 4, shift, verify, cancel
Ramp 30% every few days. Run an inbox placement test on the new platform before full volume, and compare it against what Smartlead was reporting.
Verify the suppression list matches exactly. Export final analytics. Then cancel.
The cost comparison, honestly
Smartlead prices by tier on mailbox and lead volume, with higher tiers for agencies and client workspaces.
Outboundry includes unlimited email accounts on every plan, Starter $39, Growth $89, Agency $399 with 20 LinkedIn seats and whitelabel. Infrastructure sits in the same product at $0.80 to $2.50 per mailbox depending on IP model and term, with domains from $5.99 a year.
Where the comparison usually turns is not per-mailbox cost but whether you are also paying for a LinkedIn tool, a warmup tool, and a data provider alongside. If you are, run the total rather than the line item. If you are email-only at high volume and happy with Smartlead’s rotation, the case for moving is weaker and worth being honest about.
The short version
For Smartlead teams the migration is the estate. Export the account list, prune the mailboxes that are not earning their place, and document the rotation and limit settings that no export carries.
Load suppressions first, bulk-connect what survived the prune, and run both platforms in parallel while you rebuild one campaign properly.
Watch per-mailbox metrics rather than averages during the overlap, at 150 mailboxes the average will tell you everything is fine right up until it isn’t.
Next: the universal migration checklist, or infrastructure cost at 10, 100 and 500 mailboxes.
Frequently asked questions
Can you export sequences from Smartlead?
No. Leads, analytics, the blocklist and your email account list export as CSV, but sequences and rotation settings do not. Document them before cancelling.
How do I move 100+ mailboxes to a new platform?
Export the account list with SMTP and IMAP details, prune any mailbox with a poor bounce or placement record, then bulk-connect the rest by CSV. Keep them connected to both platforms during the overlap.
Will moving off Smartlead affect deliverability?
Not inherently. Reputation lives with the domain and mailbox. What does change is that tuned rotation and ramp settings have to be recreated, so document them before you go.
Should agencies migrate all clients at once?
No. Move one client workspace at a time, starting with the smallest, so any problem surfaces on a low-volume account rather than across the whole book.
