Mailchimp to Klaviyo Migration: Moving Without Losing Lists, Flows, or Deliverability

Klaviyo’s Mailchimp integration is a one-way sync with a narrow, documented scope. Klaviyo’s guide to migrating from Mailchimp (opens in new tab) lists four kinds of data it brings across: subscriber information including unsubscribes and cleaned contacts, Mailchimp audiences, email receives, clicks and opens, and Mailchimp ratings. The same guide says tags don’t sync, and that the campaign engagement it collects covers campaigns sent in the last 90 days.

A Mailchimp to Klaviyo migration that keeps your lists, flows and deliverability intact therefore depends on three things the integration doesn’t handle: the Mailchimp export, the order the steps happen in, and a warming plan for the new account.

We’re a Klaviyo partner, and what follows is the sequence we’d walk a Shopify brand through once the decision to move is made. When Klaviyo describes how Mailchimp behaves, or Mailchimp describes Klaviyo, that’s a vendor describing a competitor’s product. Both companies revise their help pages, so re-read the one your decision depends on. Mailchimp publishes a guide for the reverse move, Klaviyo to Mailchimp, along with its own migration tools, so each direction has a vendor guide.

Mailchimp and Klaviyo organize the same subscribers differently, connect to Shopify differently, and bill on different units. Each vendor documents its own side of those three differences.

On data model, Mailchimp stores contacts in audiences and organizes them with tags, groups and segments. Klaviyo stores profiles and organizes them with lists, segments and profile properties. The two vendors recommend the same shape. Mailchimp’s page on unsubscribes (opens in new tab) says “If you have multiple audiences for a single organization, it’s best to manage 1 primary audience, and use tags to organize contacts.” and Klaviyo’s subscriber migration guide (opens in new tab) recommends that you “maintain one main email list in your account” as a starting point.

On Shopify, Mailchimp’s help center (opens in new tab) says its app “will connect a single Shopify store to your Mailchimp audience.” Mailchimp’s Shopify syncing documentation (opens in new tab) says the initial sync brings existing customers with their subscription status, and lists nine storefront events that sync to Mailchimp, from product_viewed to checkout_completed, and five Mailchimp events that sync back to Shopify, including email_opened and sms_clicked. Klaviyo’s Shopify data reference (opens in new tab) says Klaviyo syncs the last 90 days of Shopify data first, then the complete history, then new data in real time, and we’ve covered how a Klaviyo setup uses that purchase history for repeat revenue separately. Klaviyo’s Shopify setup guide (opens in new tab) also documents an optional sync from Klaviyo back to Shopify.

Does Mailchimp still integrate with Shopify? It does. Mailchimp’s newsroom post dated October 26, 2021 (opens in new tab) announced “a new direct integration available today” and Shopify’s help center (opens in new tab) points merchants to the Mailchimp app in the Shopify App Store. Mailchimp, on its connect page, and Klaviyo, in its guide to syncing Shopify subscribers (opens in new tab), each recommend leaving the marketing checkbox at Shopify checkout unselected by default.

On billing, Mailchimp charges on contacts stored and Klaviyo charges on active profiles, and the two definitions treat unsubscribed contacts differently. The billing section below gives each vendor’s wording.

Mailchimp has also shipped Shopify-specific work in 2026. Its June 17, 2026 newsroom post (opens in new tab) says “Mailchimp now automatically syncs Shopify’s B2B company data, so wholesale buyers and corporate clients are tagged and segmented without any manual setup.” A brand that sells wholesale through Shopify has a documented reason to weigh that B2B sync before deciding.

The integration connects with a Mailchimp API key and runs one historical sync. Klaviyo’s Mailchimp guide (opens in new tab) says “When you first integrate Klaviyo and Mailchimp, we will sync all your contacts and the last 90 days of campaign data. This is called a historical sync, and only occurs once.”

After that, the guide says existing audiences sync every 30 minutes and new audiences or campaigns sync every 6 hours. The 90 days applies to campaign engagement. Contacts sync in full.

Profile data is limited. Klaviyo’s guide says only names, email addresses, Mailchimp ratings and contact locations sync, and states “Klaviyo’s built-in Mailchimp integration does not sync any of your tags.” Whole campaigns don’t come over either. Klaviyo collects Received Email, Opened Email and Clicked Email for campaigns that have finished sending within the last 90 days, and it excludes campaigns that were part of an A/B test.

The install screen has three advanced options, and two of them affect what you can do later. “Collect open and click data for Mailchimp campaigns” brings the engagement history that the warming section below depends on. Limiting the sync to specific audiences has a cost Klaviyo states directly: “If you only sync contacts from specific audiences, your Mailchimp ratings (even for those synced contacts) won’t sync to Klaviyo.”

Klaviyo’s general guide to moving from another email service provider (opens in new tab) describes these integrations as “meant for one-time use to migrate your contacts into your new Klaviyo account.” Everything outside that scope moves by export or gets rebuilt.

Mailchimp has two exports, and they hold different things. Mailchimp’s contact export page (opens in new tab) says “You can export an entire audience, a segment, a tag, or a group. Exports can include subscribed, non-subscribed, unsubscribed, and cleaned contacts.” The columns include TAGS, NOTES, MEMBER_RATING, and the consent record: OPTIN_TIME, OPTIN_IP, CONFIRM_TIME and CONFIRM_IP. The contact export is how you keep those opt-in timestamps and IP addresses.

The contact export has limits Mailchimp lists itself. The page says “Contact exports don’t include email report data, like open and click rates.” It also names signup source and purchase history among eight things the export leaves out, and says “Contact exports and their CSVs are available in your account for 30 days.” Mailchimp notes that only Owners and Admins can export audiences, and that archived contacts export separately from active ones.

The full account export covers what the contact export doesn’t. Mailchimp’s account export page (opens in new tab) lists nine categories, including a Reports folder with open and click data for individual contacts, and a Templates folder described as “A folder with HTML files for all your email templates.” Of the two exports, it’s the only one that holds engagement history older than the 90 days Klaviyo syncs. Mailchimp limits the request: “You’re allowed 1 account export per 24-hour period.” and “Allow up to 24 hours for the export if you have a lot of data.”

Plan to document automations, signup forms and segment definitions by hand before you start. We’d run both exports before anything is disconnected, and pull these from the Mailchimp account:

The table pairs each Mailchimp concept with where it lands in Klaviyo.

Does Klaviyo import Mailchimp tags? Not through the integration. Klaviyo’s guide has you export tagged contacts from Mailchimp as a CSV and import them as custom properties, which you can then use in segments, flow filters and dynamic content. Mailchimp’s tags page (opens in new tab) defines them plainly: “Tags are labels you create to help organize your contacts.”

Groups follow the same route. Mailchimp’s groups page (opens in new tab) says “Group preferences are saved as audience field data in each subscriber profile.” so they arrive in the contact export as columns, and each column can be imported into Klaviyo as a property. Mailchimp also notes that unsubscribed contacts keep their group designations, so those columns are populated for contacts you won’t be mailing.

Segments are the first full rebuild. Mailchimp lets you export a segment as a static CSV of the contacts in it at that moment, and the conditions that define the segment aren’t part of that file. Write down each segment’s conditions in Mailchimp, then recreate them against Klaviyo’s profile properties and synced metrics. Our guide to building segments in Klaviyo covers the condition types you’ll be rebuilding with.

Automations are the second. Mailchimp’s help center calls the feature marketing automation flows: the help page (opens in new tab) still has customer-journeys in its URL and opens with “Marketing automation flows help you build dynamic, automated marketing paths for your contacts.”

Older accounts may also run classic automations. Klaviyo’s guide calls all of them automations and says to recreate them as flows, which means rebuilding each trigger, delay, filter and message. If cart recovery is on the list, our walkthrough of the abandoned cart email flow covers the structure.

Forms can’t be pointed at the new platform. Klaviyo’s guide says “You won’t be able to redirect forms created in Mailchimp to Klaviyo.” and offers three routes: rebuild in Klaviyo’s form builder, switch to a third-party list growth tool with a Klaviyo integration, or connect a custom form through your ecommerce platform.

Can you export Mailchimp templates to Klaviyo? Only some of them. Klaviyo’s guide, describing Mailchimp’s interface, tells you to export a template as HTML from its drop-down menu. Mailchimp’s own template export page (opens in new tab) is narrower: “This process is only for templates that you have custom-coded.” and “Drag-and-drop templates cannot be exported.” Mailchimp’s page governs Mailchimp’s product, so a template built in the drag-and-drop builder won’t export through that menu.

The account export is a second source of HTML. Mailchimp says it includes a folder of HTML files for all your email templates, plus the HTML and text content of regular emails you’ve sent.

Imported HTML has two costs in Klaviyo. The first is merge tags: Klaviyo’s guide says “Klaviyo and Mailchimp use different template tags to insert dynamic content in your emails.” and publishes an eight-row mapping, including |UNSUB| to {% unsubscribe %} and |FNAME| to {{ first_name }}. Klaviyo won’t accept a non-transactional HTML template that lacks an unsubscribe tag. The second cost is editing, which Klaviyo states as “Please note that going forward, you will have to directly edit the HTML in order to change the template.”

Klaviyo recommends rebuilding templates in its own drag-and-drop builder and offers the HTML route as the alternative for teams short on time. Plan a rebuild, and schedule it against the warming calendar. Google’s sender guidelines (opens in new tab) say “If you change the format of your bulk emails, gradually increase the sending volume of messages with the new format.”

Klaviyo’s guide says “Migrating from Mailchimp to Klaviyo requires four key steps:” and lists integrating your ecommerce platform, integrating Mailchimp, migrating templates, and sunsetting the Mailchimp account. Three documented behaviors make the order inside those steps matter.

The first is the Shopify connection. Klaviyo’s Mailchimp guide (opens in new tab) warns: “Failure to disconnect your old integration could result in double opt-in emails sending to your existing subscriber list.” The guide says Mailchimp’s Shopify connection has to come off before Mailchimp is integrated with Klaviyo, and Klaviyo’s Shopify guide says to disconnect the prior platform before integrating Shopify with Klaviyo. So Mailchimp for Shopify comes off before either Klaviyo integration goes on.

Mailchimp’s disconnect instructions (opens in new tab) describe two parts: “To disconnect Mailchimp for Shopify, you’ll need to revoke API access in Mailchimp, and then uninstall the app from your Shopify account. When you disconnect, you can choose whether to keep or remove your Shopify data from your Mailchimp account.” We’d keep the Shopify data in Mailchimp until every export is finished. Shopify’s page on uninstalling apps (opens in new tab) adds that some apps leave code in the theme after uninstalling, and that “Uninstalling the app from your Shopify admin doesn’t cancel external charges.”

Two things to check before you disconnect. Klaviyo’s sequence removes Mailchimp’s Shopify connection at the start, so identify which of your Mailchimp automations rely on store data and decide what covers them in the meantime. Mailchimp’s connect page also tells merchants who use its Order Notifications to turn off Shopify’s own notifications to avoid duplicates. If you did that, decide what sends order notifications after the cutover.

The second behavior concerns profiles Klaviyo already holds. Klaviyo’s guide says: “If a profile already exists in Klaviyo as an active profile before you add the Mailchimp integration, and it has been cleaned/bounced in Mailchimp, it won’t be suppressed in Klaviyo.”

Klaviyo’s checklist puts the Shopify integration first, which creates profiles from your Shopify customers before Mailchimp connects. A Shopify customer whose address hard bounced in Mailchimp fits that description. Klaviyo’s fix is to export those contacts from Mailchimp as a CSV and upload them to the suppression list in Klaviyo.

The third is hygiene during the overlap. Klaviyo’s guide says “If you begin cleaning contacts in Mailchimp before removing the integration, these contacts will be suppressed in Klaviyo.” That follows from the ongoing sync: existing audiences sync every 30 minutes while the integration is connected, so changes to cleaned status in Mailchimp keep arriving in Klaviyo. Finish list cleanup in Mailchimp before you connect the integration, or wait until after you’ve removed it.

Two settings to decide before the import runs. Klaviyo’s contact import guide (opens in new tab) says to turn off a live welcome series before importing so existing contacts don’t receive welcome messaging. And if you enable Klaviyo’s optional sync to Shopify for all profiles, Klaviyo’s Shopify guide says it covers profiles “added through list imports, even if they have not interacted with your Shopify store.” so the import can create Shopify customer records.

Put together, the sequence we’d follow looks like this:

For the API key, use Mailchimp’s own path: Mailchimp’s API key page (opens in new tab) says “Click your profile icon and choose Profile.” and then “Click the Extras drop-down then choose API keys.” After forms are swapped, Klaviyo’s guide suggests waiting a few days and watching the Mailchimp audiences, because new subscribers still arriving there mean a form was missed.

Klaviyo’s test before removal is specific: “Enter a test email into your sign-up form and other list growth tools, abandon a cart, and sign up for your newsletter to trigger a welcome series.” Removing the integration doesn’t undo the import. Klaviyo says “Audiences and profiles synced from Mailchimp to Klaviyo won’t be removed in Klaviyo if you disable or remove the Mailchimp integration.”

Unsubscribes have a different scope on each platform. Mailchimp’s unsubscribe documentation (opens in new tab) says “Mailchimp treats all audiences in your account independently. When a contact unsubscribes from an audience, they opt out of marketing emails and SMS messages for that audience only.” Klaviyo’s subscriber migration guide, describing how it handles Mailchimp data, says “In MailChimp, if someone is suppressed in any list, they will be globally suppressed in Klaviyo.”

For an account with several Mailchimp audiences, the numbers will change on arrival. A contact who unsubscribed from one audience and is still subscribed in another arrives in Klaviyo suppressed. Your suppressed count in Klaviyo won’t match the unsubscribed count of any single Mailchimp audience, and your sendable count will be lower than the sum of subscribed contacts across audiences. Reconcile against the combined exports, not against one audience.

Klaviyo records where those suppressions came from. Its page on suppressed profiles (opens in new tab) says a suppression synced from a provider such as Mailchimp shows the reason User suppressed. For a profile that already exists in Klaviyo when Mailchimp connects, the Mailchimp guide says “we use the more recent consent status based on its timestamp.”

Double opt-in is set in three separate places. In Klaviyo it’s per list: Klaviyo’s double opt-in page (opens in new tab) says “Double opt-in can be set at the list level.” and “List imports do not trigger double opt-in.” while the Mailchimp guide notes that every Klaviyo list starts as double opt-in. In Mailchimp, the double opt-in page (opens in new tab) says “Double opt-in for email contacts can only be enabled for Mailchimp signup forms.” Shopify has its own store-level setting, which Shopify’s help center (opens in new tab) says requires the Online Store sales channel.

That default matters for new signups after the cutover. If your Mailchimp forms ran single opt-in, a rebuilt Klaviyo form on a default list adds a confirmation step your subscribers didn’t have before. Decide the setting per list before the new forms go live.

Ratings need care if you use them to choose who gets suppressed. Klaviyo’s guide to migrating a branded sending domain (opens in new tab) says, as Klaviyo’s advice about Mailchimp’s rating, that senders moving from Mailchimp should suppress contacts with a 1 star rating. Mailchimp’s ratings page (opens in new tab) describes how the rating is built: “To determine contact ratings, Mailchimp monitors regular and A/B testing emails only. Activity from ads, automations, and landing pages is not included.” The rating reflects campaign activity, so check a contact’s automation engagement in Mailchimp before suppressing on rating alone.

SMS is a separate workstream. Mailchimp’s contact export puts them in a separate SMS folder with fields including acquisition time, revocation time and subscription status. Klaviyo’s guide to moving from another SMS provider (opens in new tab) covers sender setup and number porting, and says “allow up to 4 weeks for the number to port into Klaviyo.”

Do you have to warm up Klaviyo after moving from Mailchimp? Klaviyo says yes. Its page on which warming process to use (opens in new tab) states “Any new sender must warm up their sending infrastructure when moving to a new email service provider, like Klaviyo.” The reason is the shared IPs a new account starts on: Klaviyo’s page on IP types (opens in new tab) says “Klaviyo automatically assigns shared IP addresses to most new accounts.”

Your domain’s history comes with you, in both directions. Klaviyo’s branded domain migration guide says “When you migrate your sending domain to Klaviyo from a prior ESP, the sender reputation associated with the domain will carry over as well.” and “Deliverability issues will not automatically resolve by switching ESPs.” The same guide says new accounts should plan to warm their sending infrastructure, so an established domain doesn’t exempt a new Klaviyo account.

Google’s guidance on volume changes applies to any platform switch. Its sender guidelines say “Start with a low sending volume to engaged users, and slowly increase the volume over time.” We cover Google’s, Yahoo’s, Microsoft’s and Apple’s rules in depth in our guide to email deliverability and sender requirements in 2026.

Klaviyo documents two processes for a new account on shared IPs, and the Mailchimp integration decides which one you get. Standard warming applies to a new customer who has engagement data or is “using a Klaviyo-built integration that syncs open and click events” according to Klaviyo’s page. Platform introduction applies to accounts with only date-based properties, such as last opened, or with no engagement data. Checking the open and click option when you connect Mailchimp is what puts a migration on the standard path, and a CSV-only migration lands on platform introduction.

Klaviyo’s standard warming guide (opens in new tab) applies to marketing branded sending domains and builds on engagement segments at 30, 60, 90, 120 and 180 days. It says “For your first campaign, we recommend that you send to fewer than 10,000 recipients.” For that first send it suggests aiming for open rates above 30%, using a segment of people who clicked in the last 30 days or subscribed within the last 15.

The cadence is in Klaviyo’s words: “For the first two weeks, focus on sending to the 30 day engaged segment. As long as your open rates remain above 20% you can relax the engagement criteria to 60 during weeks 3 and 4. After four weeks of sending with at least 20% open rates, you can relax the engagement criteria to 90 days.” If open rates fall below 20%, Klaviyo says to keep sending to the current segment and pause the move to the next one. These are Klaviyo’s thresholds, and the same page warns that Apple Mail Privacy Protection inflates open rates.

The synced Mailchimp data covers campaigns from the last 90 days, so it supports the 30, 60 and 90-day segments. The 120 and 180-day segments need older engagement, which is in the Reports folder of the Mailchimp account export.

Platform introduction uses fixed caps. Klaviyo’s platform introduction page (opens in new tab) says it opens up volume “over the course of about 30 days.” For daily senders, Klaviyo’s table caps the first four days at 2,000, 4,000, 8,000 and 12,000 subscribers. For one send a week, it runs 2,000, 4,000, 8,000, 14,000, 21,000, 31,500, 47,250 and 65,000 across weeks one through eight.

Klaviyo also has an in-app version called guided warming. Its guided warming page (opens in new tab) lists four prerequisites, including at least 5,000 active profiles and at least 100 email opens or clicks in the last 30 days, which Klaviyo says can be synced from Mailchimp. The feature expires if unused: “Note that if you have qualified for warming but did not send an email in the last 45 days, you will see the warming notifications dismissed. Once dismissed, guided warming cannot be re-enabled.” A long gap between connecting Mailchimp and the first Klaviyo campaign costs you that guidance.

Klaviyo’s two guides give different timing for flows. The Mailchimp guide says to recreate automations and then “Once your Klaviyo flows are live, turn off all of your automations in Mailchimp to ensure that you’re not double-emailing people.” The warming guide says “Once you have created and sent to all your engaged segments, it’s now time to turn on your automations or flows. It’s critical that you only turn on flows that have historically performed well.”

The warming guide defines flows that have performed well with four thresholds: open rates above 40%, click rates above 1%, and unsubscribe and complaint rates each below 0.1%. For flows that haven’t met them, Klaviyo suggests waiting until you’ve sent campaigns from Klaviyo for 2 weeks before turning on the welcome series, 30 days for abandoned cart, and 30 to 60 days for browse abandonment.

That leaves you a sequencing decision for each automation. Pull each one’s rates from the Mailchimp account export and compare them to Klaviyo’s four thresholds. Flows that clear them are candidates to go live in Klaviyo early, and the rest follow Klaviyo’s delayed schedule.

The fixed constraint is that no trigger runs live on both platforms. Mailchimp’s classic automations page (opens in new tab) says of abandoned cart and order notification emails: “These automations will reach anyone who abandons a cart or places an order in your store, even if they haven’t subscribed to your marketing emails.” A cart flow live in both accounts sends two recovery emails to the same shopper.

A new Klaviyo account sends from Klaviyo’s shared domain until you set up your own. Klaviyo’s page on branded and shared sending domains (opens in new tab) says “Any company is eligible to create a branded sending domain.” and “If you are a bulk sender by most inbox providers’ standards, you must set up a branded sending domain to successfully land in inboxes.”

Google defines the term. Google’s sender guidelines FAQ (opens in new tab) says “A bulk sender is any email sender that sends close to 5,000 messages or more to personal Gmail accounts within a 24-hour period. Messages sent from the same primary domain count toward the 5,000 limit.”

It adds “Bulk sender status doesn’t have an expiration date.” Because Google counts by primary domain, a domain that qualified while sending through Mailchimp still qualifies after the move. Yahoo’s sender FAQ (opens in new tab) declines to give a figure: “We will not specify a volume threshold.”

Klaviyo’s branded sending domain setup guide (opens in new tab) says “Klaviyo requires up to 3 CNAME or 4 NS records for email authentication, and one TXT record for domain ownership verification.” The NS records belong to the dynamic routing option, which Klaviyo recommends, and the CNAMEs to the static option for DNS providers that don’t support NS records. Klaviyo’s migration guide adds a check: “Ensure that the branded sending subdomain is not already being used within your DNS.” The setup guide also says to pause all sending before activating your first marketing branded sending domain.

Mailchimp’s records are a different set. Mailchimp’s email authentication overview (opens in new tab) says “For your emails to be properly authenticated, your domain’s DNS records need to be updated with 2 CNAME records (for DKIM) and 1 TXT record (for DMARC).” Mailchimp’s setup page (opens in new tab) has you create them as a DKIM record and a DMARC record. Klaviyo’s migration guide says to remove a prior provider’s records once you no longer send there, and notes that sending from that platform on your branded domain stops when they’re gone.

We’d handle Mailchimp’s records in two parts. Remove the two DKIM CNAMEs only after Mailchimp sending has fully stopped. Keep a DMARC record published on the domain throughout, because Mailchimp’s one TXT record is the DMARC record and Google’s guidelines for bulk senders say “Set up DMARC email authentication for your sending domain. Your DMARC enforcement policy can be set to none.” Both vendors say DNS updates can need as long as 48 hours to take effect.

Both vendors change their prices, and yours depends on your tier, so compare what each platform counts.

Mailchimp bills on stored contacts in tiers, with a send limit tied to the tier. Mailchimp’s pricing plans page (opens in new tab) says “Subscribed, unsubscribed, and non-subscribed contacts are included in your contact count.” and “Archived, cleaned, and deleted contacts don’t count toward your contact total or the price of your marketing plan.” Going over the contact limit on a monthly plan doesn’t interrupt service, the page says. Mailchimp adds a charge instead.

Klaviyo bills on active profiles and emails sent. Klaviyo’s billing page (opens in new tab) defines the unit: “Any profile, regardless of consent status, that can be emailed through Klaviyo is considered an active profile.” Suppressed profiles stay in the account for reporting and leave the billable count once they’re fully processed as suppressed. On sends, the page says “Klaviyo charges for any messages that leave the system: any received or bounced emails count toward your plan limit, but skipped emails do not.”

The difference shows up in two groups. Unsubscribed contacts count toward a Mailchimp tier and don’t count in Klaviyo once processed. Never-subscribed contacts, such as Shopify customers who didn’t opt in, count on both platforms as long as Klaviyo can email them.

Klaviyo enforces the match between plan and profile count. Klaviyo’s FAQ on its February 18, 2025 billing changes (opens in new tab) says “customers will be required to be on an email plan that matches or exceeds their active profile count.” The Mailchimp import and the Shopify sync both add profiles, so the active profile count after those two syncs sets your starting tier. Size the plan from that number, not from your Mailchimp subscribed count.

Reducing the count takes a manual step. Klaviyo’s billing page says “Your plan does not automatically downgrade when you reduce profiles; you must choose a lower tier in the Billing page after your billable profile count has updated.” It also says the count can take up to 72 hours to refresh after you suppress or delete profiles. During the overlap, Mailchimp continues to bill on its stored contact count, unsubscribed contacts included.

Klaviyo’s migration wizard isn’t for this move. The wizard’s help article (opens in new tab), published on September 14, 2026, says “The migration wizard is currently in closed beta.” It moves existing Klaviyo accounts from Klaviyo’s legacy sending platform to its newer infrastructure, and the article says “If you are moving to Klaviyo from a different email service provider, this is not the guide you want.”

Klaviyo’s branded sending domain setup guide was last edited on September 30, 2026, and it describes the dynamic and static routing options covered above. Klaviyo published a separate article on managing DNS records for a dynamic branded sending domain (opens in new tab) the same day. If your DNS notes for Klaviyo predate that, re-read the setup guide before you add records.

Klaviyo Starter in Shopify is a newer, embedded version of Klaviyo inside the Shopify admin, with help articles published September 21, 2026. Klaviyo’s comparison of Starter and klaviyo.com (opens in new tab) says “The app creates (or connects to) a real Klaviyo account.” and lists what’s only available at klaviyo.com: “Setting up a dedicated sending domain, browsing and editing profiles, building segments, multi-step automations, and SMS and other channels.” The sending domain and segment work covered above is on that klaviyo.com-only list, so run the migration in the full platform.

Mailchimp changed how API keys work. Its API key page says “Effective June 22, 2026, any new API key you generate will expire 1 year after its creation date. API keys created before June 22, 2026 aren’t affected by this change and won’t expire.” Klaviyo’s Mailchimp guide recommends creating a new key for the integration, and a key created today falls under the new rule.

Mailchimp gives you two ways to stop: pause or delete. Mailchimp’s page on pausing or canceling (opens in new tab) says “Pause your account to stop billing and save your account data for later use.” A pause runs for 3 or 6 months, and Mailchimp limits accounts to 2 pauses every 12 months.

A pause ends without action from you. Mailchimp’s plan change page (opens in new tab) says “Your account automatically unpauses and resumes billing after the 3 or 6-month period. Be sure to reactivate automations after restarting.” If you pause as a fallback, put the end date on a calendar and decide before it arrives.

Deletion is permanent. Mailchimp says “After an account is deleted, it’s permanently closed and cannot be restored.” and “We remove all data associated with audiences, campaign archives, and reports.” Confirm that the contact exports, the account export, and your automation and segment notes are stored outside Mailchimp before you delete. The contact export files stay available in the account for 30 days, so download them before you delete.

Once the account is live in Klaviyo, our Klaviyo email marketing agency team offers a free Growth Audit of the account you’ve just built.