Google updated its URL best practices and logged the change on October 23, 2026: it recommends separating words with hyphens (-) rather than underscores (_), and now explains why. It affects how any site creates addresses for new pages. It is not a ranking change.
What we know
- What Google logged: the Search Central changelog entry for October 23 says the URL structure best practices were updated to clarify word separation with hyphens versus underscores. The reason, per Google: to keep the documentation in sync with its "The Non-Canonical Cabinet" video series.
- What the guide says: separate words with hyphens instead of underscores. According to Google, underscores are used to join concepts that belong together, as in function names like format_date, while hyphens clearly mark where each word ends. It adds that underscores aren't recommended "for historical reasons."
- The examples: the guide recommends an address like /summer-clothing/filter?color-profile=dark-grey and lists as not recommended the same with underscores and one with the words run together, /greendress.
- Page date: the guide shows a last-updated date of October 21, 2026; the changelog records it on the 23rd.
- What it doesn't say: the guide says nothing about changing URLs that already exist.
What changes and what doesn't
The hyphen recommendation isn't new in Google's documentation; what's new is the explanation and the examples. For pages you create from today, the rule is clear: words separated by hyphens, no underscores, no words run together.
Nothing changes for a site that already ranks with underscores: Google announces no penalty and doesn't ask anyone to migrate. Changing the address of a page that already gets traffic means redirecting it, updating links and waiting for Google to process the move, with a risk of losing rankings along the way. For a readability gain, it rarely pays off.
How to tell if it affects you
- Look at your URLs. Open your sitemap (usually yourdomain.com/sitemap.xml) and look for underscores or run-together words in page and post addresses.
- In WordPress, post slugs are generated with hyphens by default. Underscores usually come from hand-typed slugs or a plugin: fix it on new pages.
- In Drupal, if you use the Pathauto module, check that its separator setting is the hyphen. Changing it only affects aliases generated afterwards, unless you bulk-regenerate aliases, which changes existing URLs.
- If you decide to change existing URLs, do it only for pages with no traffic or during a planned redesign, with a 301 redirect from the old address to the new one, an updated sitemap and internal links, and keep an eye on Search Console for the following weeks.
- Write the rule down. Anyone publishing on your site should use lowercase, hyphens and full words, without unnecessary dates or IDs.
Related: How Long Google Takes to Crawl and Index: Its Own Numbers
Sources
- Google Search Central, "URL structure best practices for Google Search," updated October 21, 2026
- Google Search Central, documentation changelog, October 23, 2026 entry
Updates: if Google makes further changes to this guide, they will be added here with a link.