Assess sources and quality
List exports and owners: CRM contacts, payments from accounting and attachments from file storage. Map every field to its destination. Normalise phone numbers and dates, inspect encoding and identify duplicates. Do not automatically remove disputed records. Agree merge rules with the data owner first.
Run a representative trial
Use an isolated environment with closed deals, empty values and multiple contacts per company. Check totals, owners, relationships and attachments as well as row counts. Retaining old identifiers in a dedicated field helps reconciliation and allows repeatable imports without duplicate records.
Plan the cutover
Define when edits stop in the old system and how final changes will be imported. Take a backup, test restoration and agree rollback conditions. Users should know which system is authoritative after launch. Track import errors and resolve discrepancies from an agreed list instead of editing records blindly.
Checklist
- Prepare field maps and merge rules.
- Reconcile relationships, totals and attachments.
- Make repeated imports idempotent.
- Agree cutover and rollback responsibilities.
Project questions
Must all history be migrated?
No. Agree retention requirements and operational value. Some history can remain in a protected archive with a defined access process.