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CRM Data Migration Checklist: How to Move to a New CRM Without Losing Data
Most CRM projects that disappoint do so because of the data, not the software. Contacts arrive duplicated, notes go missing, deals lose their history, and the team goes back to spreadsheets. A migration done properly avoids all of that. This checklist is the process we follow at WebsNexus when moving clients from spreadsheets or one CRM to another.
By WebsNexus · October 20, 2026 · 3 min read · Updated October 20, 2026
CRM migration checklist
| Step | What to do | Done when |
|---|---|---|
| 1. Inventory | List every data source: spreadsheets, old CRM, inboxes, forms | Every source and record count is listed |
| 2. Decide what to keep | Archive dead leads and test data instead of migrating them | Keep and archive rules are agreed |
| 3. Map fields | Map each old field, owner and stage to the new CRM | Mapping document is approved |
| 4. Clean | Standardise formats, fix broken records, merge duplicates | Duplicate and error counts are near zero |
| 5. Test import | Import a sample and have real users check it | Users sign off the sample |
| 6. Live migration | Freeze changes, import everything, re-link relationships | Record counts match |
| 7. Verify and switch | Spot-check records, then retire the old system | Team works only in the new CRM |
Before you start: decide what to migrate
Not everything deserves to move. Leads that went cold years ago, test records and duplicates only clutter the new system. Agree simple rules, such as migrating every customer and every lead active in the last two years, and archive the rest in a file you can search if needed.
Also decide what history matters. Notes, emails, call logs and deal history are often the most valuable data and the easiest to lose, because they live in separate tables or attachments.
Field mapping is the real work
Every field in the old system needs a home in the new one: standard fields, custom fields, pipeline stages, owners, tags and dates. Where the new CRM works differently, decide how to translate. For example, three old statuses might become one pipeline stage plus a tag.
Write the mapping down and get it approved by the people who use the data every day. It is much cheaper to fix a mapping document than a migrated database.
Cleaning and de-duplication
Standardise phone numbers to one international format, trim and lower-case emails, fix country and date formats, and split combined fields such as full names. Then find duplicates by email, phone and company, and decide which record wins and what is merged.
Expect this step to take longer than you think if the data came from spreadsheets kept by several people over several years.
Test, then migrate, then verify
Always run a test import first. Ask the salespeople, support staff or managers who know the data to check real records: their own customers, open deals, recent notes. Fix what they find and repeat if needed.
For the live migration, pause changes in the old system, import everything, re-link contacts to companies, deals and notes, then compare record counts and spot-check records. Keep the old system read-only for a few weeks as a safety net.
Common migration mistakes
Migrating everything without cleaning it. Losing relationships between contacts, companies and deals. Forgetting attachments and email history. Switching over on a busy day. And not training the team, so they keep using the old spreadsheet.
Frequently asked questions
How do I migrate data to a new CRM?
Export all sources, decide what to keep, map every field, clean and de-duplicate the data, run a test import that users check, then run the live migration and verify record counts before retiring the old system.
How long does a CRM migration take?
Moving spreadsheets into a CRM usually takes 1 to 2 weeks, and a CRM-to-CRM migration 1 to 3 weeks, depending on data volume and quality.
How much does CRM data migration cost?
At WebsNexus, spreadsheet cleanup and import starts from $300, migration from a legacy system or old CRM from $600, and a full migration with dashboards and automation from $1,500.
Can you move us from Salesforce to HubSpot?
Yes. WebsNexus migrates between HubSpot, Salesforce, Zoho CRM, Pipedrive and custom CRMs, keeping the links between contacts, companies, deals and notes.
Will we lose our notes and email history?
Not if they are included in the field mapping. Notes, activities and attachments are migrated as their own step and checked during the test import.