Email Migration Checklist: Complete Step-by-Step Guide

Audit Current Email Environment

Document number of users, mailbox sizes, total data volume, and current email platform

Identify All Email-Related Services

List calendars, contacts, distribution lists, shared mailboxes, and public folders

Document Third-Party Integrations

Identify CRM, marketing tools, helpdesk systems, and other apps connected to email

Review Current Email Policies

Document retention policies, security settings, and compliance requirements

Assess Network Bandwidth

Test upload speeds and determine if network can handle migration traffic

Choose Target Email Platform

Select Microsoft 365, Google Workspace, or other platform based on requirements

Select Migration Method

Choose IMAP, native tools, or third-party migration service

Create Migration Timeline

Set dates for pilot, waves, and final cutover with buffer time

Assign Migration Team Roles

Designate project manager, technical lead, communications lead, and support team

Develop Rollback Plan

Document steps to revert to old system if critical issues occur

Budget Approval

Get approval for licenses, migration tools, and professional services

Remove Inactive User Accounts

Archive or delete accounts for departed employees

Clean Up Mailboxes

Ask users to delete old emails, empty deleted items, and reduce mailbox sizes

Archive Old Data

Move emails older than X years to archive or backup

Remove Duplicate Distribution Lists

Consolidate and clean up email groups

Purchase Licenses

Buy sufficient licenses for all users on new platform

Verify Domain Ownership

Add and verify your domain in new email platform

Create User Accounts

Set up all user accounts in new system (bulk import recommended)

Configure Security Settings

Set up MFA, password policies, and security defaults

Set Up Email Authentication

Configure SPF, DKIM, and DMARC records (but don't update MX yet)

Configure Retention Policies

Set up email retention and archiving policies

Select and Purchase Migration Tool

Choose native tools or third-party migration service

Configure Source Connection

Set up connection to current email system (IMAP, admin credentials, etc.)

Create User Mapping File

Map source email addresses to destination accounts

Test Migration with Pilot Group

Migrate 5-10 IT users to test process and identify issues

Create Communication Plan

Schedule announcements for before, during, and after migration

Prepare User Documentation

Create guides for new email system, mobile setup, and common tasks

Schedule Training Sessions

Plan live or recorded training for users on new platform

Set Up Support Channels

Prepare helpdesk, FAQ, and escalation procedures

Start Email Migration

Begin migrating emails in planned waves or batches

Monitor Migration Progress

Check migration dashboard regularly for errors or failures

Migrate Calendars and Contacts

Transfer calendar events and contact lists

Migrate Distribution Lists

Recreate email groups and distribution lists

Migrate Shared Mailboxes

Transfer shared mailboxes and set permissions

Address Migration Errors

Resolve any failed migrations or data issues immediately

Verify Data Migration Complete

Confirm all emails, calendars, and contacts migrated successfully

Send User Credentials

Provide login information and temporary passwords to users

Update Email Client Settings

Configure Outlook, mobile devices, and other email clients

Test Send/Receive

Verify users can send and receive emails on new platform

Update MX Records

Point domain's MX records to new email platform

Monitor Mail Flow

Watch for delivery issues after DNS changes (24-48 hours)

Verify All Data Migrated

Compare item counts between old and new systems

Test All Email Functionality

Verify sending, receiving, calendars, contacts, and mobile access

Check Third-Party Integrations

Verify CRM, marketing tools, and other integrations work correctly

Review Migration Logs

Check for any errors or warnings in migration reports

Conduct User Acceptance Testing

Have key users verify their data and functionality

Provide Ongoing Support

Maintain enhanced support for 2-4 weeks post-migration

Track Support Tickets

Monitor and resolve migration-related issues

Conduct User Training

Deliver scheduled training sessions on new platform

Send User Survey

Gather feedback on migration experience and new platform

Keep Old System Active

Maintain old email system for 30 days as backup

Create Final Backup

Export final backup of old system before decommissioning

Cancel Old Email Service

Terminate old email platform subscription

Optimize New Platform Settings

Fine-tune security, retention, and performance settings

Document Lessons Learned

Record what went well and what could be improved

Complete Project Closeout

Final report to stakeholders with metrics and outcomes