1
Audit.
We review your Mailchimp account first: list health, suppression status, engagement history, automation logic and every integration that needs rebuilding.
Mailchimp to Klaviyo Migration, Done Properly
Moving from Mailchimp to Klaviyo should feel like an upgrade, not a risk.
We're an official Klaviyo partner and we handle the whole move: auditing and cleaning your list, mapping your segments, rebuilding your flows and protecting your deliverability. Your Mailchimp automations keep running until the new flows are live, so there's no gap in sends.
Is it time to move from Mailchimp?
Mailchimp suits plenty of businesses. Brands tend to start comparing companies like Mailchimp when email becomes a serious revenue channel and the limits start to show:
- flows can't react to what customers buy or browse
- segments are built on contacts rather than customers
- revenue reporting doesn't match what your store says
- you're paying for a big list that mostly doesn't open
For growing eCommerce brands, Klaviyo is the alternative we recommend most often because it's built around your store data. Our Klaviyo vs Mailchimp comparison covers the differences in detail. Still weighing up other platforms? Read our email marketing platforms compared guide.
What does a Mailchimp to Klaviyo migration involve?
2
List cleaning.
Engaged subscribers move across cleanly. Unengaged contacts are checked against suppression history and spam complaints before we decide whether to import them at all.
3
Segment mapping.
Your Mailchimp tags and groups become proper Klaviyo segments built on purchase history, engagement and lifetime value.
4
Flow rebuilds.
We don't copy automations across. Each flow is rebuilt in Klaviyo with the right triggers, logic and timing for your customers.
5
Domain set-up and warm-up.
We authenticate your sending domain in Klaviyo. If you send in volume, we warm up gradually before going to full volume.
6
Tracking checks and cutover.
Your store integration, conversion tracking and revenue attribution are checked before go-live. Then the cutover happens once, at the end.
We don't call a migration finished until revenue is attributing correctly and every flow is live with accurate data.
Will you lose any subscribers or data?
No. We export your full subscriber list, engagement history and suppression data before anything moves. Unsubscribes and suppressions come across too, so nobody who opted out gets emailed by mistake.
What we may leave behind is dead weight: contacts who haven't engaged in a long time. Klaviyo bills you on active profiles, so importing them costs you money and drags down deliverability. We'll show you the numbers and agree it with you first.
How long does a migration take?
1 to 2 weeks
For most brands
That covers list cleaning, flow rebuilds and integration checks.
The cutover itself is a single event at the end, so your customers won't notice the switch. Larger accounts with lots of integrations or high send volumes can take longer. If yours is one of them, we'll tell you at the start.
What happens to your Mailchimp automations in the meantime?
They keep running. Your Mailchimp automations stay live until the Klaviyo flows are built, tested and switched on. There's no gap in coverage.
Keep your Mailchimp account open until your last send has gone and you've exported everything you need.
How do you protect deliverability during the move?
Your domain authentication doesn't move with you. Klaviyo gives you its own DNS records for a dedicated sending domain, so SPF, DKIM and DMARC all need setting up and checking before your first send. Keep your Mailchimp records in place until your last Mailchimp send, then tidy them up.
If you send in volume, we build in a warm-up. We start with your most engaged subscribers and increase volume step by step, so mailbox providers learn to trust the new set-up. It's the same approach we use to protect deliverability on every Klaviyo account we run.
What should you do before you start?
A bit of preparation makes the move faster and safer. Before the audit, it helps to have:
- admin access to your Mailchimp account and your store platform
- access to your domain's DNS settings, or the details of whoever manages them
- a list of every tool connected to Mailchimp: store, forms, reviews, loyalty, ads and anything else
- your current automations written down, even roughly, with what each one is meant to do
- your brand assets and any templates you want to keep
Don't cancel anything yet. Your Mailchimp account stays open until the last send has gone and you've exported everything.
What changes when you move to Klaviyo?
Some things work differently, so it's worth knowing before you start.
| Audiences become lists. | Klaviyo's Mailchimp integration turns your Mailchimp audiences into Klaviyo lists. Each person has one profile, with lists and segments sitting on top. |
|---|---|
| Your history comes with you. | The integration brings across unsubscribes and cleaned contacts, plus up to 90 days of campaign open and click data. |
| Tags and groups become segments. | Rather than tagging people by hand, segments update themselves from what customers buy, browse and open. |
| Automations become flows. | Flows can be triggered by store events, such as a product viewed or an order placed, not just a sign-up date. |
| Reporting ties to orders. | Revenue is attributed to the flows and campaigns that drove it, so you can see what each email earns. |
| You're billed on active profiles. | Suppressed profiles don't count towards that limit, which is why we clean the list before importing it. |
Which flows do we rebuild first?
We rebuild the flows that earn most first, so your revenue is covered from day one.
Welcome series.
Every new subscriber gets it, so it goes live before the cutover.
Abandoned cart and checkout.
Usually the flow that recovers the most revenue.
Browse abandonment.
Something Klaviyo's store data makes far easier than before.
Post-purchase.
Thanks, delivery information and the route to a second order.
Win-back and sunset.
Bringing back lapsed customers, then quietly removing people who never engage.
Once those are live, we add the flows specific to your business, such as back in stock or replenishment reminders.
Common migration mistakes
Importing everyone.
It pushes up your Klaviyo bill and can hurt deliverability from the first send.
Forgetting suppressions.
People who unsubscribed or complained must stay suppressed. We import them as suppressed, not as subscribers.
Copying automations as they are.
It recreates Mailchimp's limits inside Klaviyo.
Switching on full volume straight away.
A new sending set-up needs to build trust with mailbox providers first.
Leaving forms pointing at Mailchimp.
Every sign-up form must point at Klaviyo by cutover day, or new subscribers go missing.
Closing Mailchimp too early.
Keep it until everything is exported and the last send has gone.
What happens after the cutover?
The migration isn't finished when the switch happens. In the weeks after, we:
- watch deliverability, complaint rates and inbox placement daily while volume builds up
- check revenue attribution matches what your store reports
- confirm every flow is triggering and every form is collecting
- review the first results with you and agree what to improve next
If you carry on with us after the move, that becomes your monthly reporting.
"I have worked with Shane and team for several years and the growth they have seen is testament to the service they deliver."
What does it cost?
We'll tell you which applies after the free audit, before any work starts.
Once you're on Klaviyo, our management tiers are indicative, not fixed. They start from around £400 a month for Campaigns, £900 for Klaviyo Essential, £1,500 for Klaviyo Growth+ and £2,400 for Bespoke. Your Klaviyo subscription is separate and billed by Klaviyo on active profiles, which is one more reason to clean your list before you move.
As an official Klaviyo partner, we receive commission from Klaviyo. We use it to fund a better service for our clients. It isn't passed back as a discount and it never decides which platform we recommend. If staying on Mailchimp makes more sense for you, we'll say so.
Prefer to stay on Mailchimp?
That's fine. Not every business needs Klaviyo.
If you'd rather stay on Mailchimp, our email marketing agency team can run it for you: audits, segmentation, automations, campaigns and deliverability. Moving is still the right call for many brands. Stair Parts Direct started with a full audit of their Mailchimp account, then moved to Klaviyo with us. It's early days, but they've already seen a marked increase in revenue.
Read the 40% More Email Revenue for Stairparts Direct in 90 Days with Klaviyo Management case study 
40% More Email Revenue for Stairparts Direct in 90 Days with Klaviyo Management
Led by:40%Read case studyIncrease in Email revenue in 90 days
Read the How We Increased Conversions for Elite Energy by 80% with SEO, PPC and Email case study 
How We Increased Conversions for Elite Energy by 80% with SEO, PPC and Email
Led by:80%Read case studyIncrease in conversions
Read the We Helped CTS UK Break £50m Turnover with 117% eCommerce Revenue Growth case study 
We Helped CTS UK Break £50m Turnover with 117% eCommerce Revenue Growth
Led by:117%Read case studyeCommerce revenue increase, CTS turnover £50m+
Who handles your migration?
Your migration is run by our permanent Klaviyo team, not freelancers. Paddy Cumiskey, our Head of Email & CRM, leads it with our Klaviyo Strategists George Newell-Hall and Polly Evans. Jon Brown (Senior Creative Lead) and Amy Gillard (Designer) rebuild your templates so your emails look right from the very first Klaviyo send.
Paddy Cumiskey
Head of Email & CRM
George Newell-Hall
Klaviyo Strategist
Polly Evans
Klaviyo Strategist
Jon Brown
Senior Creative Lead
Amy Gillard
Designer
Results after the switch
Read the JT Atkinson Increased Klaviyo Flow Revenue by 107% with Expert Management case study 
JT Atkinson Increased Klaviyo Flow Revenue by 107% with Expert Management
Led by:107%Read case studyIncrease in Klaviyo flow revenue with expert management.
Read the Gingerlily Grew US Email Revenue from Klaviyo by 163% case study 
Gingerlily Grew US Email Revenue from Klaviyo by 163%
Led by:163%Read case studyIncrease in Klaviyo US revenue YoY
Frequently asked questions
Will we lose subscriber data when we move?
No. We export your full list, engagement history and suppression data before anything moves, so opt-outs stay opted out and your history comes with you.
How long does a Mailchimp to Klaviyo migration take?
One to two weeks for most brands, with a single cutover at the end. Larger or more complex accounts can take longer and we'll tell you at the start.
What happens to our Mailchimp automations during the move?
They keep running until the Klaviyo flows are built, tested and live, so there's no gap in coverage.
Which companies are like Mailchimp?
The alternatives we work with most are Klaviyo, HubSpot, ActiveCampaign, Dotdigital and Salesforce Marketing Cloud. For eCommerce brands, Klaviyo is usually the strongest fit because it's built around store data.
Can you move our templates and sign-up forms as well?
Yes. We rebuild your templates in Klaviyo and set up Klaviyo sign-up forms, so your list keeps growing from cutover day.
Do we need a Klaviyo partner to migrate?
No, but it helps to have a team that has done it before. We're an official Klaviyo partner, listed in Klaviyo's partner directory.
What do you need from us to start?
Admin access to Mailchimp and your store, access to your domain's DNS settings and a list of the tools connected to Mailchimp. We'll take it from there.
Will our sign-up forms keep working?
Yes. We set up Klaviyo sign-up forms and switch every form to point at Klaviyo by cutover day, so no new subscribers are missed.
What happens to people who unsubscribed in Mailchimp?
They come across as suppressed profiles, so they stay opted out and won't be emailed from Klaviyo.
Is Klaviyo better than Mailchimp?
For growing eCommerce brands, it usually is, because it's built around your store data. Segments and flows can react to what customers buy and browse. Mailchimp suits smaller businesses and simpler needs where cost comes first. Our Klaviyo vs Mailchimp comparison covers the differences in detail. If staying on Mailchimp makes more sense for you, we'll say so.
Can Klaviyo import directly from Mailchimp?
Yes. Klaviyo has a Mailchimp integration that syncs your audiences into Klaviyo lists, along with subscription status, unsubscribes and cleaned contacts. It can also bring across up to 90 days of campaign open and click data. We still check suppressions after the sync and upload any that were missed, before the first send from Klaviyo.
How much does a Mailchimp to Klaviyo migration cost?
If you're moving to Klaviyo for the first time, we can usually absorb the cost and do it for free. Sites with more dynamic set-ups and integrations take more work, so it may cost up to £750. We'll tell you which applies after the free audit, before any work starts. Your Klaviyo subscription is separate and billed by Klaviyo.
Should we run Mailchimp and Klaviyo at the same time?
Briefly, yes. Keep Mailchimp open until the last send has gone and everything is exported. Klaviyo's own guidance is to test each new flow before setting it live, then turn off the matching automation in your old platform so nobody gets the same email twice. We plan a single cutover so the overlap is short and controlled.
Will moving to Klaviyo hurt our deliverability?
Not if it's done carefully. Your domain needs authenticating again in Klaviyo, with SPF, DKIM and DMARC checked before the first send. Google advises raising sending volume gradually, starting with engaged subscribers. So if you send in volume, we warm up step by step. We also import only people worth emailing, which helps from day one.
Do we lose our past campaign reports when we leave Mailchimp?
Some history comes across. Klaviyo's Mailchimp integration can sync up to 90 days of campaign open and click data. Older reports stay in Mailchimp, so export anything you want to keep before you close the account. We'll tell you what to export during the audit. Your Klaviyo reporting then builds from cutover day onwards.
Get your free migration audit
- No long contracts. If we’re not delivering you can leave. We’d rather earn the next month than lock you in.
- Permanent specialists on your account. Strategists, CRM specialists and designers who work for us, not freelancers.
- No sales team. Your first call is with the people who would actually run your account.
Tell us about your Mailchimp account. One of our Klaviyo specialists will review it, tell you honestly whether moving makes sense and set out what the move would involve.
No hard sell. We don't have sales staff.