The Ultimate CRM Data Migration Checklist for UK Businesses

Why a Checklist Is Non-Negotiable for CRM Migration

A CRM holds some of your most sensitive and business-critical data: customer contacts, deal history, communication records, and the pipeline your revenue depends on. Migrating it without a structured checklist is how records get lost, GDPR obligations get missed, and go-lives turn into emergencies.

This crm data migration checklist is designed for UK businesses running any CRM migration — whether you're moving from Salesforce to HubSpot, Dynamics to Pipedrive, or a legacy on-premise system to a cloud platform. Work through each section in order. Don't skip phases to save time — the pre-migration phases are where the expensive mistakes are prevented.

Phase 1: Pre-Migration (Weeks 1–4)

Business & Stakeholder Preparation

• [ ] Identify project sponsor — senior stakeholder with authority to make decisions and remove blockers
• [ ] Map all CRM users — who uses the system, how, and how often? Their input shapes the migration approach
• [ ] Document current CRM usage — which objects, fields, and workflows are actively used vs. legacy noise
• [ ] Define go-live date — work backwards to confirm the timeline is achievable
• [ ] Identify blackout periods — financial year-end, quarter-close, peak sales periods to avoid
• [ ] Agree parallel run policy — will both systems run simultaneously for a period post go-live?
• [ ] Brief all CRM users on the timeline and what to expect

GDPR Compliance — Pre-Migration

• [ ] Identify all personal data in scope — contacts, leads, email records, call notes, any special category data
• [ ] Document lawful basis for processing (typically legitimate interests for B2B CRM data) — update ROPA
• [ ] Issue Data Processing Agreement (DPA) with your migration service provider before sharing any data
• [ ] Assess DPIA requirement — if migrating 100,000+ records or special category data, a Data Protection Impact Assessment is required
• [ ] Check cross-border transfer mechanisms — if source or destination system stores data outside the UK
• [ ] Review opt-out lists — contacts who have opted out of communications must be excluded or flagged in migrated data
• [ ] Document DSAR process for the migration window — how will you respond to Subject Access Requests if mid-migration?

Data Audit and Quality Assessment

• [ ] Export full schema inventory from source CRM — every object, every field, population rates
• [ ] Identify actively used vs. empty fields — fields populated for <5% of records are candidates for exclusion
• [ ] Run duplicate detection — most CRMs accumulate duplicates over time; address before migration
• [ ] Identify data type mismatches — fields with inconsistent formats (dates, phone numbers, currencies)
• [ ] Flag records requiring cleansing — invalid emails, missing mandatory fields, outdated contact data
• [ ] Categorise data for migration — Active (full migrate), Archive (read-only export), Delete (no longer needed)
• [ ] Produce data quality report — document findings and agree remediation approach with stakeholders

Field Mapping Specification

• [ ] Map every source field to destination — for each object: source table/field → destination table/field, with data types and transformation logic
• [ ] Handle object model differences — e.g., Salesforce Leads vs. HubSpot Contacts; document conversion decision
• [ ] Map relationship chains — Accounts → Contacts → Deals → Activities; relationship integrity must survive migration
• [ ] Identify custom fields — every custom field in source needs an explicit destination mapping or documented exclusion
• [ ] Define lookup tables — for picklist fields, map every source value to destination value (don't assume identical)
• [ ] Get field mapping sign-off from CRM admin and business stakeholders before any technical work begins

Phase 2: Migration Build and Testing (Weeks 3–8)

Environment Setup

• [ ] Provision destination CRM environment — don't migrate to production for testing
• [ ] Configure destination schema — create all custom fields and objects before migration begins
• [ ] Configure user accounts and permissions in destination (at least for migration team)
• [ ] Document rollback procedure — if production migration fails, how do you revert? Test this.

Test Migration Execution

• [ ] Run initial test migration against a subset of records (10% sample)
• [ ] Run automated reconciliation — record counts, field completeness, relationship integrity
• [ ] Review exception report — records that failed validation; investigate root cause
• [ ] Fix issues in source or transformation layer — not manually in the destination
• [ ] Run full test migration against complete dataset
• [ ] User acceptance testing (UAT) — key CRM users validate their data in the test environment
• [ ] Document outstanding issues and agree resolution before production migration

GDPR Compliance — During Testing

• [ ] Confirm test environment access controls — only migration team members, no wider access
• [ ] Do not use production personal data in non-production environments where avoidable — consider pseudonymisation for testing
• [ ] Log all access to personal data during testing

Phase 3: Migration Day

Pre-Cutover Checklist

• [ ] Confirm source system freeze time with all stakeholders — the point at which no new data enters the source CRM
• [ ] Communicate freeze to all users — including mobile users, integrations writing to the source
• [ ] Take final backup of source system before cutover begins
• [ ] Confirm support team availability — on-call migration team throughout cutover window
• [ ] Confirm rollback threshold — at what point (time or error count) do you invoke the rollback plan?

Cutover Execution

• [ ] Run final delta extraction from source CRM (records created/updated since test migration)
• [ ] Apply transformation pipeline to delta records
• [ ] Load all records to production destination CRM
• [ ] Run production reconciliation report — record counts must match; investigate any discrepancy before proceeding
• [ ] Validate critical records manually — spot-check 20–30 high-value accounts to confirm data integrity
• [ ] Verify relationship integrity — a sample of Contacts should have correct associated Companies; Deals should link to correct Contacts
• [ ] Confirm opt-out exclusions are correctly applied — no opted-out contacts should be marked as marketing-eligible

Go-Live

• [ ] Enable user access to destination CRM
• [ ] Brief users on go-live — where to log any data issues they find
• [ ] Disable write access to source CRM (read-only for reference during parallel run)
• [ ] Notify all integrated systems of the CRM switch — any system writing to the old CRM must be reconfigured

Phase 4: Post-Migration

Reconciliation and Validation

• [ ] Run final reconciliation report comparing source extract totals to destination totals
• [ ] Resolve outstanding exceptions from migration day — any records that failed to load
• [ ] Collect user feedback in the first 48 hours — data issues spotted by users are the best quality check
• [ ] Document any variances and their resolution for the audit trail

GDPR Compliance — Post-Migration

• [ ] Update ROPA to reflect new system as primary CRM
• [ ] Confirm source system decommission plan — personal data in old CRM must be deleted (not just archived) once no longer needed
• [ ] Request deletion certificate from old CRM vendor if cloud-hosted
• [ ] Store DPA, LIA, and ROPA update in compliance records — retain for ICO audit purposes
• [ ] Brief DPO or data protection lead on migration completion and GDPR documentation

Source System Decommission

• [ ] Define retention period for source CRM data — legal, contractual, or regulatory minimum
• [ ] Export any data required for retention (CSV exports, structured archive)
• [ ] Delete personal data from source system after retention period expires
• [ ] Document deletion (date, method, confirmation)

Working with a Professional Migration Partner

A comprehensive crm data migration checklist like this one takes 8–12 weeks to execute properly. If you're doing this alongside a day job, plan accordingly — or work with a migration specialist who runs this process every week.

Book a free CRM migration audit with 2-IC DATA SYSTEMS. We'll review your source CRM, run through this checklist with you, and give you a fixed-price migration proposal within 48 hours.