Sitemap index

A sitemap index points Google to multiple sitemap files. Each child sitemap can hold up to 50,000 URLs or 50 MB uncompressed. The index lets you split by section, subdomain, or language, and keep one URL to submit.

You likely do not need one on a small site. A single sitemap is fine until you near the limits, or want cleaner split reports by area. It helps on sites like yourproduct.com with /blog, /docs, and /app, or en and fr versions.

Nested indexes are not allowed. Your index lists only sitemap files, not other indexes. Frameworks and platforms often generate an index once you cross a limit, so check before you build one by hand.

<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <sitemap>
    <loc>https://yourproduct.com/sitemaps/sitemap-blog.xml</loc>
    <lastmod>YYYY-MM-DD</lastmod>
  </sitemap>
  <sitemap>
    <loc>https://yourproduct.com/sitemaps/sitemap-docs.xml</loc>
    <lastmod>YYYY-MM-DD</lastmod>
  </sitemap>
</sitemapindex>

Place it at a stable URL, for example https://yourproduct.com/sitemap.xml. The lastmod on each entry tells crawlers when that child sitemap changed, not the pages inside it. Keep loc absolute and on the same host when you can. Use an ISO date format.

1. 1

   Add the index URL in the Sitemaps report

   Open Search Console, pick your property, go to Sitemaps, and submit https://yourproduct.com/sitemap.xml. You submit the index, not the child files.

2. 2

   Wait for processing

   Google reads the index, then fetches each listed sitemap. It shows status, when it was last read, and how many URLs it discovered from each file.

3. 3

   Check coverage by area

   If you split by section or language, issues are easier to trace. Fix the specific child sitemap that throws errors, then resubmit the index or wait for recrawl.

You can also ping the index URL in your deploy script. Submission by Search Console is usually enough for a small site, as of 2026.

• Create one when your single sitemap nears 50,000 URLs or 50 MB uncompressed.
• Create one to split areas: /blog, /docs, /shop, or by language like /en and /fr.
• Keep one sitemap if you have a few hundred URLs. The index adds overhead with no gain.

A neat split helps with ownership. Your docs generator can update its own sitemap, and your blog build can update another. The index sits above them, stable and small.

• Linking another index inside an index. Not allowed.
• Letting lastmod lie. Update the child sitemap’s timestamp when it changes, then reflect that date in the index.
• Listing sitemaps on a different protocol or host you do not control.
• Including child sitemaps that list noindex, 404, or redirected URLs. Clean those out at source.
• Moving the index URL without redirecting. Keep it stable, or 301 to the new location.
• Blocking sitemap files in robots.txt. Do not do that.