How to migrate from Mailchimp to HubSpot and Validate Your Data After Migration

By Team MultiSync Made Easy
Published on September 9, 2026   |  
6 Mins Read
How to migrate from Mailchimp to HubSpot and Validate Your Data After Migration

Moving marketing data from one platform to another is rarely just an export-and-import job. If you plan to migrate from Mailchimp to HubSpot, there are fields, consent, segments, campaign history, and plenty of small details that need attention.

A good Mailchimp to HubSpot migration approach should leave your data organised, usable, and easy to check. The goal is not only to move contacts, but to make sure the information still works properly once it reaches the new platform.

In this blog, we will go through the main migration checklist, data validation steps, common mistakes, and a practical way to migrate Mailchimp to HubSpot with less manual work. Additionally, we will see where a Salesforce ETL tool can fit into connected data workflows.

A Complete Checklist to Migrate Mailchimp to HubSpot

Before you migrate from Mailchimp to HubSpot, take some time to understand what you already have. This small step can save a lot of cleanup later. HubSpot also recommends reviewing source data, field mappings, destination fields, testing, and the imported results before completing a migration.

Audit Your Mailchimp Data
First, make a list of your audiences, contacts, custom fields, tags, segments, campaigns, automations, templates, engagement records, and consent information. Mailchimp can contain different contact statuses and campaign details, so knowing what you actually need makes the next steps easier.
Clean the Data Before Moving
There is not much point in taking old data problems into a new CRM. Remove obvious duplicates, standardise values, check missing information, and review inactive or outdated contacts before you migrate from Mailchimp to HubSpot.
Map Fields Carefully
Create a simple field mapping sheet before importing anything. Match each Mailchimp field with the correct HubSpot property and decide how dates, dropdowns, phone numbers, consent fields, and custom information should be handled.
Protect Subscription and Consent Data
This part needs extra attention because not every contact has the same marketing status. Mailchimp can contain subscribed, unsubscribed, non-subscribed, and cleaned contacts. Make sure these statuses are reviewed and carried over correctly instead of treating every contact the same.
Recreate Segments and Marketing Logic
Your Mailchimp audience structure may not directly match HubSpot. Look at how your segments, tags, lists, and automation rules are being used today, then recreate the important logic in HubSpot so your team does not lose useful targeting.
Test First
It is better to find a mapping problem with 100 records than with 100,000 records. Run a smaller test first and check for formatting issues, duplicates, missing properties, incorrect values, and association problems before the complete Mailchimp to HubSpot migration.
Validate After the Import
Do not simply look at the “successful import” message and move on. Compare record counts, important fields, statuses, associations, and sample records between both systems. This gives you a much clearer idea of whether the migration actually worked as expected.
Keep a Backup
Always keep your original export somewhere safe before making major changes. Mailchimp allows account data to be exported, although the exact information available can vary depending on the type of data being exported. Having that backup also makes comparison easier if something looks wrong later.

The Best Way to Migrate Data From Mailchimp to HubSpot Without Data Loss

Manual CSV work can be manageable for a small database, but it becomes difficult when you have multiple datasets, recurring updates, or complex mappings. A structured migration workflow can make the process easier to control.

MultiSync Made Easy is a Salesforce-native ETL and integration platform that supports both Mailchimp and HubSpot among its connected applications. It can help teams move and synchronise data through configurable workflows instead of relying only on repeated manual exports.

  • Bi-directional data synchronization keeps connected records aligned.
  • Advanced data mapping matches fields across different systems.
  • Filters and transformations apply data rules before records move.
  • Real-time or scheduled sync options support different workflow needs.
  • Record monitoring and error logs help identify failed transfers.
  • Legacy data imports support historical and one-time migration projects.

The platform also works across 100+ applications and provides a unified dashboard for connected workflows. For teams that need a Salesforce ETL tool alongside broader integration requirements, this can be useful when marketing data also needs to connect with Salesforce.

Validate Your Data After Migration

Once you migrate from Mailchimp to HubSpot, spend some time checking the transferred data before depending on it for live marketing activities. A few simple checks can catch issues that may otherwise become much harder to fix later.

  • Compare record counts – Check source and destination totals for important datasets.
  • Review sample records – Pick contacts from different audiences and compare their information.
  • Check field mappings – Make sure important values reach the correct HubSpot properties.
  • Review subscription status – Confirm subscribed, unsubscribed, and other contact statuses were handled properly.
  • Check segments and tags – Make sure important audience structures are still usable.
  • Review errors – Look through import reports and fix failed or incomplete records.
  • Test marketing workflows – Check that lists, journeys, and campaigns are working with the new data.
  • Document differences – Keep track of information that could not be transferred or needs manual work.

The important thing here is not to check only whether records exist. Look at whether the records are correct, complete, and useful for the marketing activities your team actually needs to run.

Common Mistakes to Avoid

Migration problems often come from small things that were missed in the beginning. Furthermore, most of them are avoidable when the team takes a little extra time before starting the actual transfer.

  • Skipping the data audit – Know what you need before moving the data.
  • Ignoring duplicates – Clean repeated and outdated records before migration.
  • Poor field mapping – Match every important source field with the right destination property.
  • Forgetting consent data – Review marketing permissions and contact statuses carefully.
  • Skipping a test migration – Test a smaller group before moving the complete database.
  • Not keeping a backup – Keep the original export available for comparison if something goes wrong.
  • Assuming every activity transfers – Check which campaign and reporting information can actually be moved.
  • Ignoring post-migration checks – A completed import does not always mean the data is ready to use.

Wrapping Up

A successful Mailchimp to HubSpot migration is about more than moving contacts from one system to another. It is about carrying useful data, permissions, structure, and customer information into the new platform without creating another cleanup task.

If you migrate from Mailchimp to HubSpot with proper preparation, field mapping, testing, and validation, the process becomes much easier to manage. Additionally, keeping a backup gives your team something reliable to compare against while you move forward.

For teams planning to migrate Mailchimp to HubSpot while also working with Salesforce, MultiSync Made Easy can provide a more connected approach to migration and synchronisation. This Salesforce native app can also help bring related data workflows together as the business grows.

Frequently Asked Questions

New to automation with MultiSync? You're not alone. Here are some answers to common questions about how MultiSync works.

Migration time depends on contact volume, data complexity, custom fields, segmentation, integrations, and validation requirements. A structured MailChimp to HubSpot migration can make planning and execution more predictable.

Yes, businesses can synchronize selected data between Mailchimp and HubSpot when ongoing connectivity is required. MultiSync Made Easy can support configurable synchronization workflows across connected business applications.

Prioritize active contacts, custom fields, subscription information, audience structures, tags, segments, and business-critical engagement data. Reviewing these elements first helps ensure the most valuable marketing information reaches HubSpot.

Automation can reduce repetitive exports, imports, mapping, and synchronization tasks. MultiSync Made Easy supports configurable workflows that can help businesses move and manage data between connected platforms more efficiently.

Businesses can reduce manual work through automated data mapping, transformations, filtering, synchronization, monitoring, and scheduled workflows. MultiSync Made Easy helps centralize these connected data processes across multiple applications.

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