Migrating from a legacy intranet to SharePoint Online works best when you treat it as a chance to declutter and rebuild better — not a lift-and-shift of everything. The approach: audit your existing content and keep only what is current and valuable, design a clean information architecture for the new portal, migrate the content that earns its place, and phase the move to minimize disruption. Done this way, migration is the first step of a better intranet rather than dragging old problems into a new system.
This guide covers the decluttering mindset, the migration phases, what to keep vs leave, and how to avoid the common pitfalls.
Migration Is a Chance to Declutter
Legacy intranets accumulate years of outdated, duplicate, and orphaned content. The biggest mistake in migration is moving all of it — you just recreate the mess in a new place. Treat migration as a content cleanup: most organizations find they should migrate far less than they expect. Less, but current and well-organized, beats everything-but-stale.
The Migration, Phase by Phase
1. Audit & inventory: Catalog existing content, owners, and what is actually used.
2. Decide what moves: Keep current, valuable content; archive or delete the rest.
3. Design the new structure: Build a clean information architecture for SharePoint Online — do not copy the old one.
4. Build the new portal: Set up sites, navigation, and branding on SharePoint Online.
5. Migrate content: Move the content that earned its place, mapping it into the new structure (manually or with migration tools).
6. Validate & launch: Check everything came across correctly, then launch with communication and a read-only overlap of the old system.
What to Migrate vs. Leave Behind
|
Migrate |
Leave behind / archive |
|
Current, accurate content |
Outdated or superseded content |
|
Frequently used documents |
Unused or orphaned files |
|
Active policies and resources |
Duplicate versions |
|
Content with a clear owner |
Content no one owns or maintains |
Quick takeaway: Migrate less, not more. A clean SharePoint intranet portal is the goal — and our rollout guide covers building it well.
Minimizing Disruption
Keep the business running through the move: communicate the change and timeline, run the new portal alongside the old (kept read-only) during a short overlap so nothing is stranded, migrate in phases rather than all at once where possible, and provide quick reference and support at launch. A planned, phased migration is far less disruptive than a big-bang cutover.
Common Migration Pitfalls
Migrating everything instead of decluttering first.
- Copying the old, broken information architecture into the new portal.
- No content owners, so quality is not maintained.
- Skipping validation, so links and content break.
- A big-bang cutover with no overlap or communication.
- Treating migration as purely technical, ignoring adoption.
Migration is as much about content strategy and information architecture as it is about moving files. Centric plans and executes SharePoint Online migrations that declutter, restructure, and launch a better intranet with minimal disruption.
Planning a migration? See the Centric SharePoint Intranet Portal or talk to the Centric team.
Frequently Asked Questions
How do you migrate an intranet to SharePoint Online?
Audit your existing content and keep only what is current and valuable, design a clean information architecture for the new portal, build it on SharePoint Online, migrate the content that earns its place into the new structure, then validate and launch with a read-only overlap of the old system. Phase it to minimize disruption.
Should we migrate all our intranet content?
No — most organizations should migrate far less than they expect. Legacy intranets are full of outdated, duplicate, and orphaned content; moving it all just recreates the mess. Declutter first and migrate only current, valuable, owned content.
How do you avoid disruption during migration?
Communicate the change and timeline, run the new portal alongside the old (read-only) during a short overlap, migrate in phases where possible, validate before launch, and provide support and quick references. A planned, phased move beats a big-bang cutover.
How long does an intranet migration take?
It depends on content volume, cleanup, and complexity — from a few weeks for a small, well-pruned migration to several months for a large, content-heavy one. The content audit and information architecture work drive much of the timeline.
Ready to migrate to a better intranet? Explore the Centric SharePoint Intranet Portal.
