Belgium. Three official languages, three communities, a compact territory. If you are a Belgian company with a website, you know the headache: how do you serve French content to Walloons, Dutch content to Flemish users, and German content to the German-speaking community, without Google mixing everything up?
That is exactly the problem hreflang tags solve. And it is a problem that concerns far more than Belgium: any company operating in multiple countries or languages is affected.
Understanding hreflang and its importance
Hreflang is an HTML attribute that tells Google the language and optionally the geographic region targeted by a page. It allows Google to serve the right version to each user based on their language and location.
Without hreflang, several problems arise: the French version of your page appears in Google.nl results, the English version cannibalises the French version for French-language queries, and Google may consider your different versions as duplicate content.
According to Daniel Waisberg, Search Advocate at Google Zurich: "Hreflang is the clearest way to communicate to Google the relationships between the different language versions of your content. Without this information, we have to guess — and we do not always guess correctly."
The 3 implementation methods
Method 1: HTML tags in the <head>
The most common method. For each page, add a tag for each language version:
<link rel="alternate" hreflang="fr-BE" href="https://www.example.be/fr/page" /><link rel="alternate" hreflang="nl-BE" href="https://www.example.be/nl/page" /><link rel="alternate" hreflang="en" href="https://www.example.be/en/page" /><link rel="alternate" hreflang="x-default" href="https://www.example.be/en/page" />
Method 2: HTTP headers
Useful for non-HTML files (PDFs, documents) or sites that generate HTML dynamically. The Link header contains the same information as the HTML tags.
Method 3: XML sitemap
For large sites (more than 1,000 pages per language), the sitemap method is more efficient. It avoids bloating the <head> of each page and centralises hreflang management. See our guide on XML sitemaps for implementation details.
Language and region codes
| Hreflang code | Target | Use case |
|---|---|---|
| fr | French (all regions) | Generic French-language content |
| fr-FR | French (France) | Content specific to the French market |
| fr-BE | French (Belgium) | Content specific to French-speaking Belgium |
| nl-BE | Dutch (Belgium) | Content specific to Flanders |
| de-BE | German (Belgium) | Belgian German-speaking community |
| fr-CH | French (Switzerland) | French-speaking Swiss market |
| fr-CA | French (Canada) | French-speaking Canadian market |
| x-default | Default version | Language selection page or English version |
Language codes follow the ISO 639-1 standard (2 letters), region codes follow the ISO 3166-1 standard (2 letters). Do not confuse language and country: fr is a language, FR is a country. fr-BE means "French for Belgium", not "Belgian" (which is not a language).
The most frequent errors
1. Non-reciprocal hreflang. If the /fr/ page points to /en/ with hreflang, the /en/ page MUST also point to /fr/. A non-reciprocal hreflang link is ignored by Google. This is the most frequent error.
2. Missing self-referencing. Each page must include itself in its hreflang declarations. The /fr/ page must have an hreflang pointing to /fr/ in addition to the other versions.
3. Incorrect language codes. Using "uk" instead of "en-GB" for the United Kingdom, or "br" instead of "pt-BR" for Brazil. Verify each code against ISO standards.
4. URL with redirect. URLs in hreflang must resolve with 200 (no redirect). If your hreflang points to a URL that redirects, Google ignores it.
5. Conflict with canonical. If the /fr/ page has a canonical pointing to /en/, the hreflang is contradictory. Each language version must have a self-referencing canonical.
6. Missing x-default. The x-default value designates the page to display to users whose language/region does not match any declared version. Its absence forces Google to guess.
Hreflang and multilingual AI visibility
In 2026, AI visibility is also a matter of language. When a French-speaking user asks Perplexity a question, the system looks for French-language sources. If your site has versions in French and English, you want the French version to be cited for French-language queries, and the English version for English-language queries.
Hreflang helps indirectly: it ensures that Google correctly indexes each language version, which improves their discovery by RAG systems. Without hreflang, Google may only index one version (often the English one), making the others invisible to LLMs.
According to Gianluca Fiorelli, international SEO consultant based in Madrid: "Multilingual SEO is the poor relation of technical SEO. Companies invest thousands of euros in translating their content, then sabotage that investment with missing or incorrect hreflang. In 2026, the impact is twofold: loss of organic traffic AND loss of AI visibility in each language market."
The specific case of Belgium
Belgium is a textbook case for multilingual SEO. With three linguistic communities in a compact territory, Belgian companies must manage subtleties that monolingual companies ignore.
The optimal configuration for a Belgian site:
fr-BEfor Belgian French-language content (note: Belgian French has lexical specificities — "septante" vs "soixante-dix")nl-BEfor Flemish content (notnl-NLwhich targets the Netherlands)de-BEif you target the German-speaking communityfr-FRif you also have clients in France (content adapted to the French market)x-defaulttowards the most universal version (often English or generic French)
For sites targeting multiple French-speaking markets (Belgium, France, Switzerland, Canada), each market deserves a specific version with local references, prices in local currency, and adapted legal notices. "Generic French" content fully satisfies no market.
Also discover how your site architecture must be designed for multilingual use, and how a technical SEO audit can identify all your hreflang errors.
FAQ
Does hreflang work on Bing?
Bing supports hreflang but also recommends using the content-language meta tag and the Content-Language HTTP header. For maximum coverage, implement both. Bing also uses the XML sitemap with hreflang annotations.
Is hreflang needed for every page or only the homepage?
Every page that has an equivalent version in another language must have hreflang annotations. The homepage alone is not sufficient. If /fr/blog/article exists and /en/blog/article exists, both must be linked by hreflang. Pages without an equivalent in another language do not need hreflang.
Subdomains or subdirectories for multilingual sites?
Both work with hreflang. Subdirectories (/fr/, /en/) are generally recommended as they inherit the authority of the main domain. Subdomains (fr.example.com) or country TLDs (example.fr, example.be) are useful if you have distinct teams per country or local hosting requirements.
How do I test my hreflang annotations?
Several tools: Aleyda Solis' Hreflang Tags Testing Tool (free, online), Screaming Frog with the "Hreflang" tab, and Sitebulb which visualises hreflang errors. Check first: reciprocity, self-referencing, code validity, and the absence of redirects on declared URLs.
Does hreflang affect crawl budget?
Indirectly, yes. Hreflang annotations help Google discover the language versions of your pages, which can increase the number of pages crawled. For very large multilingual sites (100,000+ pages per language), the sitemap method is preferable to avoid bloating the <head> and unnecessarily consuming crawl budget.
What to do if not all pages are translated?
Only add hreflang annotations for pages that have an equivalent in the other language. If /fr/page-a exists but /en/page-a does not, do not create an hreflang annotation for that page. The x-default will serve as a fallback for English-speaking users who land on a French-only page.
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