What are the key steps in a CRM data migration?

CRM data migration steps: (1) export and audit all data from the old system, (2) clean duplicates and fill required fields, (3) map fields between old and new CRM, (4) do a test import with a small subset first, (5) validate the test import thoroughly, (6) run the full migration during low-activity period, (7) verify critical records immediately after import, (8) archive or deactivate old system rather than deleting it immediately.