Migrate to Send & Retain from the email platform you use now.
Bring contacts and unsubscribes over first. Your agent rebuilds your flows as paused automations, and you switch one trigger at a time.
✓Free to start. Unlimited contacts on every tier.
Inventory before cutover
Inventory
Source material read
Rebuild
Created paused
Verify
Real inbox test
Switch
One trigger first
Destination automation
Paused until validation and explicit cutover
[ 01 / 06 ]Choose your platform
Which platform are you moving from?
Each guide says exactly what moves automatically and what your agent rebuilds.
Klaviyo
A read-only connector reads your flows, their steps, and their subject lines.
ActiveCampaign
The connector lists your automations and reads their steps where the API allows.
Mailchimp
The connector reads legacy classic automations. Automation flows are rebuilt from your notes.
Resend
Keep sending through your Resend key while you add contacts and automations.
SendGrid
Keep sending through your SendGrid key while templates and automations move.
Postmark
Move transactional emails one at a time, with Postmark running until each one works.
Mailgun
Swap Mailgun calls one email type at a time, suppressions first.
Customer.io
Move the email parts of your journeys. Push, SMS, and in-app steps stay behind.
[ 02 / 06 ]What moves automatically
Can my flows be imported automatically?
Only from five platforms, and not equally. Everywhere else, your agent rebuilds flows from what you export or describe. Contacts and unsubscribes move by CSV from any platform.
Klaviyo
Flows, steps, delays, and subject lines
Nothing extra. Your agent works from the real flows
ActiveCampaign
Every automation; steps where the API opens them
Your notes for steps the API won't return
HubSpot
Workflows and their steps, without subject lines
The copy and subject lines of your HubSpot emails
Mailchimp
Classic automations only
Screenshots or notes for automation flows (Customer Journeys)
Brevo
No workflows. Brevo's API doesn't expose them
Screenshots or notes for every workflow
Resend, SendGrid
No connector. Keep sending through your key
Your code, templates, and what you describe
Postmark, Mailgun
No connector
Your code, templates, and what you describe
Customer.io
No connector
Journey screenshots, exports, and notes
[ 03 / 06 ]Step by step
How do I migrate to Send & Retain?
The same six steps from any platform. The order matters more than the speed.
Set up sending
Your agent creates your domain and hands you the DNS records to add. Or connect your own Resend or SendGrid key in the dashboard.
Import your unsubscribes first
Export suppressed, bounced, and unsubscribed contacts and import them as your block list before a single send.
Import contacts
Import your contact export as a CSV. Every column becomes a contact attribute, and lists become tags.
Rebuild flows as paused automations
Your agent reads them through a connector, or rebuilds them from what you export or describe. Every automation is created paused.
Test in a real inbox
Send each rebuilt email to yourself and check the copy, the links, and the timing.
Switch one trigger at a time
Point one event at Send & Retain, turn the old flow off, and keep the old platform until it all works.
[ 04 / 06 ]Honest limits
What doesn't move when I switch?
Your contacts, unsubscribes, and the shape of your flows move. A few things stay on the old platform.
- Open and click history. A contact who last opened in 2019 starts cold here.
- Newsletter blasts. Every email goes to one person, by design. Keep a newsletter tool if you send them.
- Images hosted on the old platform. Move them before you cancel, or migrated templates break.
- Imported complaints become blocks you can remove. Complaints recorded here never can be.
[ 05 / 06 ]Example prompts
What can I ask my agent during a migration?
Paste these into Claude, ChatGPT, Cursor, or any agent connected to Send & Retain.
Inventory
“List every flow we pulled from our old platform, which are live, and which you'd retire.”
Rebuild
“Rebuild our welcome flow here as a paused automation, and show me each step before I turn it on.”
Templates
“Rewrite our three most-sent emails as templates in our brand and send me a test of each.”
Check
“Before I switch, confirm our unsubscribes and bounces are imported and blocked.”
[ 06 / 06 ]Related
Still deciding?
Questions people ask us
Move one flow first. Keep the rest running.
Import your unsubscribes, rebuild one flow as a paused automation, and switch it when it works.