Mailchimp to ConvertKit

Do not import garbage. Before exporting, remove:

Unsubscribed - ConvertKit won't mail them anyway.
Bounced - these are dead addresses and will wreck your new sender reputation.
Inactive - anyone who hasn't opened or clicked in 12 months is dead weight. Remove or segment into a "win-back" tag.

Every unengaged contact you bring over gets counted against your ConvertKit plan and hurts your deliverability. Be ruthless here.

In Mailchimp: Audience → All contacts → Export Audience. Include all merge fields, tags, and groups. You'll get a zip with separate CSVs for subscribed, unsubscribed, and cleaned.

Only the subscribed CSV goes into ConvertKit. Open it and verify:

✓ Email addresses look clean
✓ Merge fields (FNAME, LNAME, etc.) are populated
✓ Tags column contains comma-separated tags
✓ Groups column maps to what you want as tags

Sign up at kit.com. Pick Creator ($25/mo for up to 1,000 subs) or Creator Pro ($50/mo with advanced features). Free tier works for initial setup.

Set your sender details under Account settings → General:

From name - your real name, not "Team [Company]". Creator emails perform better.
From address - use your actual domain, not gmail.com.
Reply-to - an address you check. ConvertKit puts heavy weight on reply rates as an engagement signal.

In ConvertKit: Subscribers → Import → CSV. Upload your cleaned Mailchimp CSV.

Map columns carefully:

Email → Email (required).
First Name → First Name.
Tags and Groups columns → Tags (ConvertKit will create any tags that don't exist).
Other merge fields → Custom Fields (create these first under Subscribers → Custom Fields).

The import runs in background. Expect 1-2 minutes per 10,000 subscribers. You'll get an email when it's done.

This is the longest step. For each Mailchimp Customer Journey:

If it's a linear email series (welcome sequence, lead magnet delivery) - rebuild as a ConvertKit Sequence. Each email becomes a step with a delay.

If it's conditional logic (if tag X, send Y) - rebuild in ConvertKit's Automations builder. Drag nodes onto the canvas: triggers, conditions, actions, emails.

Don't try to migrate 20 automations in one sitting. Rebuild your welcome sequence first, activate it, test with a fresh subscription, then move to the next.

Signup forms need to move. For each Mailchimp form:

Embedded form on your site - create an equivalent ConvertKit form, replace the embed code on your site.
Popup/slide-in - ConvertKit has these as form types. Rebuild.
Landing pages - ConvertKit's landing page builder is stronger. Rebuild anything you need. Update URLs everywhere they're shared.

Don't forget forms in blog post bodies, Substack-style embeds, or lead magnets in your email footer.

Critical. Since 2024, Gmail and Yahoo require authenticated sending for bulk senders. In 2026, it's universal - unauthenticated email goes to spam.

In ConvertKit, go to Account settings → Email settings → Domain authentication. Enter your domain. ConvertKit gives you three DNS records to add:

SPF   TXT   v=spf1 include:_spf.convertkit.com ~all
DKIM  CNAME ck._domainkey → (provided value)
DMARC TXT   v=DMARC1; p=none; rua=mailto:you@domain.com

Add these in your DNS host (Cloudflare, Namecheap, etc.). Propagation takes up to 24 hours. ConvertKit shows a green check once verified.

Send your first ConvertKit broadcast to the full list. Make it useful - a welcome-back note, an update on the switch, or just your normal newsletter. Don't announce the switch if nobody asked - subscribers don't care which ESP you use.

Monitor the first send:

Open rate should be within 10% of your Mailchimp average. If it's catastrophically lower, check spam placement with Gmail's Inbox Tester or Mail-Tester.com.

Keep Mailchimp active for 2 weeks as insurance. Once you've sent 2-3 successful broadcasts from ConvertKit, downgrade Mailchimp to free or cancel entirely.