hreflang for language and regional URLs

What it is

hreflang is a signal that tells search engines a page has equivalent versions in other languages or regions. It lives on a <link rel="alternate"> element, an HTTP Link header, or a <xhtml:link> entry in an XML sitemap. Each alternate carries a BCP 47 language tag such as en, en-GB, fr-CA, or zh-Hant.

<link rel="alternate" hreflang="en-GB" href="https://example.com/en-gb/" />
<link rel="alternate" hreflang="en-US" href="https://example.com/en-us/" />
<link rel="alternate" hreflang="fr-CA" href="https://example.com/fr-ca/" />
<link rel="alternate" hreflang="x-default" href="https://example.com/" />

Why it matters

Without hreflang, search engines guess which version of a page to surface. A user in Paris may get the US English page; a user in Quebec may get the page intended for France. hreflang removes that guesswork, reduces duplicate-content confusion across localised URLs, and improves click-through because the result matches the user's language and region.

It does not influence ranking on its own. It is purely a swap signal: same query, better-matched URL.

How to implement

• Use BCP 47 codes. Language only (en, de), or language plus region (en-GB, pt-BR). Region alone (hreflang="GB") is invalid. Script subtags are allowed where they disambiguate, e.g. zh-Hans and zh-Hant.
• Self-reference. Every page must list itself among its alternates.
• Reciprocal links. If page A points to page B, page B must point back to page A. One-way links are ignored.
• x-default. Add a hreflang="x-default" entry for the URL shown when no other alternate matches the user's locale. This is typically a language picker or the default-region homepage.
• Pick one delivery method. Use HTML <link> for static pages, the HTTP Link header for non-HTML resources such as PDFs, and the XML sitemap for sites with many alternates — mixing them on the same URL set creates conflicts.

A sitemap entry covers all alternates of a URL in one place:

<url>
  <loc>https://example.com/en-gb/</loc>
  <xhtml:link rel="alternate" hreflang="en-GB" href="https://example.com/en-gb/" />
  <xhtml:link rel="alternate" hreflang="fr-CA" href="https://example.com/fr-ca/" />
  <xhtml:link rel="alternate" hreflang="x-default" href="https://example.com/" />
</url>

Common mistakes

• Using a country code as a language code (hreflang="UK" instead of en-GB).
• Pointing alternates at URLs that redirect or 404.
• Forgetting the self-reference. Google then ignores the whole cluster.
• Mixing hreflang declarations in HTML, headers and sitemaps — pick one source of truth.
• Setting hreflang on canonicalised-away pages. Each alternate should be the canonical URL of its locale.