CRM data migration is where a lot of otherwise solid rollouts run into trouble. The assumption is that moving records from point A to point B is straightforward. In practice, every system stores data a little differently, and the gaps between field structures, record types, and relationship logic are where data gets lost, duplicated, or scrambled. Taking a methodical approach before you touch the export button saves a lot of cleanup on the other end.

Why CRM Migrations Go Wrong

Most migration failures are not technical failures — they are planning failures. The technical work of extracting a CSV and importing it into a new system is not complicated. What goes wrong is everything around it: field structures that do not match up, relationship records that import as orphans, activity history that the new platform cannot receive in the format the old one exports, and data quality issues that were hidden in the old system and become obvious in the new one.

A contact record in HubSpot looks different from the same contact in Zoho, which looks different from a custom database schema. "First name, last name, email" maps cleanly. Custom fields, multi-select properties, deal stages with internal logic, and linked company records often do not. Understanding those gaps before the migration starts is the work that determines whether the rollout goes smoothly.

Audit Before You Export

The first step is understanding what you actually have. Export a sample of your current records and look at them carefully. How complete are the records? How many duplicate contacts exist? Are company relationships linked correctly, or are contacts floating without an account? Are there records from years ago that nobody would miss? Cleaning your data before the migration is almost always easier than cleaning it after, and it gives you a more accurate picture of what you are actually migrating.

  • Check for duplicate contacts and merge or remove them before export
  • Verify that key fields like email, phone, and company name are populated where they need to be
  • Identify records that can be archived rather than migrated — dead leads from five years ago do not need to follow you to the new system
  • Document which fields in the old system map to which fields in the new one, including any fields that will need to be created in the destination
  • Flag any multi-select or picklist fields where the values differ between systems

Build Your Field Map Before Touching the Import

A field map is a document — a spreadsheet works fine — that lists every field in the source system, the corresponding field in the destination system, and any transformation needed. Phone number formats, date formats, boolean fields stored as text: these differences seem minor until they cause import errors or silent data corruption.

Custom fields in the destination system usually need to be created before the import. Building them during the migration rush is a reliable way to introduce errors. Create every field you need in the new system, validate the field types match what you are importing, and then do the first test import. The field map also serves as documentation after the migration — if something looks wrong six months later, you have a record of what came from where.

Test on a Subset First

Do not migrate everything at once on the first try. Take a representative sample — maybe 50 to 100 records that cover different record types and relationship scenarios — and run the migration on those. Review the output in the new system before proceeding. This is how you catch field mapping errors, encoding problems, and relationship breaks before they affect every record you have. If anything looks wrong in the test, you want to find it now.

A good test set includes: contacts with and without linked companies, deals in different pipeline stages, records with and without custom field data, and at least a few records with activity history if you are migrating that too. The goal is to surface every variation in your data before it becomes a problem at scale.

Handling Attachments and Activity History

Contacts and companies are usually straightforward to migrate. The harder parts are activity history, notes, attachments, and deal or pipeline records. Some systems let you export these in a structured way; others do not. Know going in what you can and cannot bring over, and make a deliberate decision about whether historical activity needs to live in the new system or whether a read-only archive of the old system is sufficient for reference.

Trying to force a full history migration when the source data is messy often creates more problems than it solves. A reasonable alternative: export everything to a structured archive (a read-only spreadsheet or a static export in the old platform), keep it accessible, and start clean in the new system. Staff can reference the archive when they need historical context without burdening the new CRM with a decade of inconsistent data.

Plan the Cutover Carefully

Decide on a cutover date and stick to it. Running two systems in parallel for more than a few days usually means data starts diverging and you end up with two incomplete sources of truth. Brief your team on the cutover plan so everyone knows which system to use after a specific date, and make sure there is a process for handling any records that were updated in the old system during the migration window.

A clean cutover checklist typically includes: final data export from old system, import to new system, validation pass on the imported records, confirmation that all integrations are pointing to the new system, and a team communication that the old system is now read-only. That last step — explicitly retiring the old system — is one that often gets skipped, and when it does, people keep entering data in two places for weeks.

After the Migration: Validation and Cleanup

Even a well-planned migration produces some cleanup work. Spot-check a random sample of records after the import — not just the test records you already reviewed, but fresh ones. Verify that key relationships are intact: contacts linked to correct companies, deals linked to correct contacts, activities linked to the right records. Run your most common reports and confirm the numbers make sense.

Build in a window for staff to flag issues before the old system is shut down. Two weeks of parallel access — where staff can look at the old system for reference but are required to enter all new data in the new one — catches most of the gaps that were not obvious during the validation pass.

If you are migrating into a custom-built system or need someone to manage the technical side of the move, visit my custom CRM & software page. For the broader rollout context, CRM implementation covers what a full deployment looks like end to end. For decisions upstream of the migration — whether to build or buy in the first place — the build vs buy breakdown and the how to choose a CRM guide are the right starting points.