To rank an international website in every language, treat each language version as its own site: pick a clear URL structure (usually subfolders), connect versions with correct hreflang tags, research keywords locally instead of translating them, earn links in each market and make every version easy for AI assistants to cite.
Most international websites are built the same way: the main version is finished, then someone translates it into three more languages and the job is marked done. Months later, the English site gets traffic and the German, French or Polish versions get almost none. The translation was fine. The SEO was never done.
This guide is for companies expanding across Europe, in the DACH region, the Nordics, Central and Eastern Europe or beyond, and for anyone evaluating a multilingual SEO agency. It covers the decisions that matter, in the order you should make them.
What makes multilingual SEO different from regular SEO?
Each language version is effectively a separate website competing in a separate market. It has different competitors, different search terms, different directories and different expectations. What carries over is your domain's authority and your technical foundation. Everything else has to be done again for each market.
There is also a distinction worth making early. Multilingual means different languages, for example English, German and French. Multi-regional means different countries, which may share a language, such as Germany, Austria and Switzerland. Many sites need both, and the structure should reflect that from day one.
ccTLD, subdomain or subfolder: which URL structure should you use?
| Structure | Example | Strengths | Trade-offs |
|---|---|---|---|
| Country domain (ccTLD) | example.de, example.fr | Clearest local signal, local trust | Each domain builds authority alone; more cost and admin |
| Subdomain | de.example.com | Can be hosted separately | Often treated more like a separate site; rarely worth it |
| Subfolder | example.com/de/ | Shares the main domain's authority; one site to maintain | Weaker country signal than a ccTLD |
| URL parameter | example.com?lang=de | None worth having | Not recommended by Google for language versions |
For most companies, subfolders are the right call. You build one strong domain and every language benefits. Country domains make sense when you have a real local entity, a local team and the budget to build links for each domain separately.
Whatever you choose, follow one rule from Google Search Central's guidance on multilingual sites: each language version needs its own URL. Do not swap the language with cookies or JavaScript on the same address, because crawlers will only ever see one version.
How do you implement hreflang correctly?
Hreflang tells search engines which page is the equivalent in another language or region, so the right version shows to the right searcher. It does not boost rankings on its own, but done wrong it creates the classic problem of the English page ranking in Germany while the German page sits unseen.
- Every version lists every version, including itself. If the English page points to German, the German page must point back to English. Missing return links are the most common reason tags are ignored.
- Use correct codes. Language in ISO 639-1 format (de, fr, ro), optionally followed by a region in ISO 3166-1 alpha-2 (de-AT, de-CH). "en-UK" is wrong; it is "en-GB".
- Add x-default for the page users should see when no language matches, often a language selector or your main English page.
- Point only to canonical, indexable URLs that return a 200 status, not redirects.
- Keep canonicals self-referencing per language. Pointing the German page's canonical to the English page tells Google to drop the German page.
- Pick one method: HTML link tags in the head, HTTP headers, or the XML sitemap. For large sites, the sitemap is easier to maintain.
Also worth knowing: Google states in the same documentation that it determines a page's language from its visible content, not from the lang attribute. So a German page with English navigation, English buttons and an English footer sends mixed signals. Localise the whole template, not only the body text.
Why is local keyword research better than translation?
Because people do not search in translations. The phrase your Romanian customers use may have no direct equivalent in German. The English term that converts best in the UK may be a minor variant in the US. Volumes, intent and competition change from market to market.
We see this on our own site. Our Romanian pages target terms like "creare site" and "agenție marketing", and our English section under /en/ targets terms foreign buyers actually use, such as "website development company Romania". The English blog is not a translation of the Romanian one. It covers different topics, chosen from separate keyword research, because the audience asks different questions.
A practical process for each market:
- Start from your service list, not your existing keywords.
- Have a native speaker brainstorm how a buyer would describe the need.
- Validate volumes and difficulty in that country's database in your keyword tool.
- Check the local results page: who ranks, what format wins, whether AI Overviews appear.
- Map one primary keyword per page and brief the writer with the local angle.
What does native-quality content actually require?
- Native or near-native writers, or at least native editors reviewing every page.
- Local proof: case studies, references and certifications relevant to that market.
- Local details: currency, units, date formats, phone numbers with country codes, local business hours.
- Local tone: German B2B buyers usually expect precise, sober copy; other markets respond to a more conversational style. Do not force one voice across all languages.
How do you build local authority in each market?
Links and mentions from sites in the target country carry more weight for that market than links from your home country. Practical sources: national industry directories, chambers of commerce, trade fair exhibitor lists, partners and distributors in the country, local press and niche publications. For service businesses, a Google Business Profile per real location, with consistent details, matters too.
How does GEO work across languages?
This is the part most international SEO guides skip. AI assistants like ChatGPT, Gemini, Perplexity and Copilot answer in the language of the question and lean on sources in that language. A buyer in Munich asking in German will mostly see German sources cited. If your only well-structured content is in English, you are invisible in that conversation.
- Make sure every language version is crawlable by AI search bots such as OAI-SearchBot and PerplexityBot, and indexed in both Google and Bing.
- Open key pages in every language with a 40 to 60 word direct answer.
- Add localised structured data: Organization, Service and FAQPage with questions in that language.
- Earn mentions on the lists and directories that AI already cites in that market.
- Test monthly in each language: ask the same buyer questions in German, French or Polish and record who gets recommended.
The full process is covered in our guide on how to get recommended by ChatGPT.
What should you ask a multilingual SEO agency?
- Who writes and edits each language, and are they native speakers?
- Will you do keyword research separately per market, or translate one list?
- How will you handle hreflang, canonicals and the sitemap, and how will you check them?
- How will you earn local links in each country?
- How do you measure AI visibility in each language?
- Can you show pages you have ranked in a language other than English?
If you are also choosing where to build the site itself, our guide to website development companies in Romania covers how to brief a team that builds multilingual from the start, which is far cheaper than retrofitting it later.
Frequently asked questions
What is multilingual SEO?
Multilingual SEO is the work of making each language version of a website rank in its own market. It covers site structure, hreflang tags, keyword research done separately in every language, native-quality content, local links and, increasingly, visibility in AI assistants in each language.
Should I use a ccTLD, a subdomain or a subfolder for each language?
For most companies a subfolder such as /de/ or /fr/ on one strong domain is the most practical choice, because all versions share the same authority. Country domains send the clearest local signal but each one has to build authority from scratch. Subdomains sit in between and are rarely the best option.
Is translating my website enough for international SEO?
No. People in different countries search with different words, and search volumes differ by market. Each language needs its own keyword research, and pages should be localised by native speakers, including examples, units, currencies and contact details that make sense locally.
What are the most common hreflang mistakes?
Missing return links between language versions, pages that do not reference themselves, wrong language or country codes, hreflang pointing to redirected or non-canonical URLs, and canonical tags that point every language to the main version. Any of these can make search engines ignore the tags.
Does multilingual SEO help with ChatGPT and Google AI answers?
Yes. AI assistants answer in the language of the question and prefer sources written in that language. A properly indexed, natively written page in German or French is far more likely to be cited in a German or French AI answer than a page in English.
Should I redirect visitors automatically based on their language?
Google advises against automatic redirects based on perceived language or location, because they can stop both users and crawlers from reaching other versions. Show a visible language switcher and, at most, a suggestion banner instead.
Expanding into new European markets?
Tell us which countries and languages you are targeting. We'll review your current structure and show you what each market needs to rank in Google and get cited by AI.
Call: +40 758 80 20 20 SEO and AI visibility