Everything in our main migration guide applies here too, but a domain merger — consolidating multiple legacy sites into one — has one extra problem worth its own explanation: redundant content across the properties you’re combining.
The Intent Mapping Framework
In a merger, you’re not just moving pages, you’re consolidating intent. It’s common to have three different pages across three different legacy domains that all cover the same topic — say, “Graduate Financial Aid.” A simple old-URL-to-new-URL spreadsheet doesn’t solve this; you need to actively consolidate:
- Audit for redundancy: identify every page across all merging domains that serves the same user intent.
- Select the “Alpha” page: choose the version with the highest authority and best UX to be the survivor.
- Consolidate and redirect: 301 redirect the “Beta” and “Gamma” versions into the Alpha page.
Done well, this doesn’t just protect your rankings — it concentrates authority that was previously split three ways, and can genuinely push you higher than any of the original pages ranked individually.
Watch for Silent Coordination Failures
In multi-domain mergers specifically, it’s common for IT to change a server configuration without telling Marketing — GA4 tags silently stop firing, and you’re flying blind through the most critical weekend of the project. Put a single “source of truth” document in place before the move, not after.
For the full migration checklist and phased rollout plan, see 10 Reasons Your Site Migration SEO Isn’t Working.
