Migrating WordPress to Next.js without losing SEO

Why SEO is the #1 migration risk

A site migration that tanks organic traffic can cost a SaaS company 6–12 months of marketing spend. I've seen it happen. Here's how to avoid it.

The pre-migration audit

Before touching any code:

1. Export all URLs from Google Search Console (last 16 months) 2. Crawl the current site with Screaming Frog 3. Export all meta titles, descriptions, and schema markup 4. Document the top 100 pages by organic traffic

The redirect map

Every old URL needs a 1:1 redirect to the new URL. Build this as a JSON/CSV file BEFORE launch.

// next.config.mjs
async redirects() {
  return [
    { source: '/blog/old-slug', destination: '/writing/new-slug', permanent: true },
    // ... all mappings
  ];
}

Schema preservation

Article, Organization, Breadcrumb schemas — all need to carry over. Use structured data testing tool to verify before launch.

Launch day checklist

• Update sitemap.xml
• Submit to Search Console
• Monitor Core Web Vitals
• Check 404 rate in Vercel analytics for 72 hours

Gotchas

• Trailing slashes: pick one convention and redirect the other
• Image URLs: if you rehost, update references in all content
• Canonical tags: don't let old and new URLs both index

On the last migration I did, we saw zero dip in organic traffic over 30 days — and a 180% increase within 90 days thanks to the performance boost.