Choose the main-language URL policy

POM Translate always prefixes additional languages. The main language is the exception: it can remain at the ordinary WordPress path or use its own language subdirectory.

Open:

Settings → POM Translate → Languages setup → Base setup

The relevant option is Use a subdirectory for the default language.

Compare the two URL structures

Suppose the main locale is Spanish, French is an additional language, and the source page slug is contacto.

With the option disabled:

Spanish: /contacto/
French:  /fr/contact/

With the option enabled:

Spanish: /es/contacto/
French:  /fr/contact/

The setting changes only the presence of the main-language prefix. Additional-language routes remain prefixed in both configurations.

Keep the main language unprefixed

Leaving the option disabled preserves ordinary WordPress URLs for the source language. This is usually the least disruptive choice when:

• an established single-language site is becoming multilingual;
• the existing source URLs are already indexed or externally linked;
• other systems expect the current unprefixed paths;
• avoiding a source-language URL migration is more important than a symmetrical structure.

An unprefixed route begins in the main-language context. Optional browser detection may redirect an eligible first visit to another configured language, but the unprefixed URL itself remains the canonical source-language route.

Language selectors and alternate-language metadata use this same policy. With Spanish as the main language and Basque at /eu/, the Spanish homepage destination is /, including while viewing /eu/. Ordinary links to the current language's homepage still use /eu/. Verify the return trip through the selector as well as the initial language change.

Prefix the main language

Enable the option when every public language should occupy a language-specific directory. This produces a consistent path pattern, but it also changes the public address of every source-language page.

When the setting is enabled, an eligible unprefixed frontend request is permanently redirected to the equivalent main-language prefixed route. The generated prefix normally uses the locale’s two-letter language code. If configured regional variants compete for that code, POM Translate generates distinct regional prefixes instead.

Do not enable this option merely to rename a language or translate a page slug. Labels, locale prefixes, and content slugs are separate concerns.

Treat either change as a URL migration

Enabling or disabling the option after launch affects far more than the homepage. Plan for posts, pages, archives, taxonomy terms, pagination, query strings, internal links, canonical URLs, alternate-language metadata, XML sitemaps, analytics, and cache entries.

Before changing a published site:

1. export or record a representative set of current source URLs;
2. decide the final canonical URL structure;
3. prepare permanent redirects from every important old path;
4. change Use a subdirectory for the default language and save;
5. update hard-coded menus, campaign links, integrations, and external profiles;
6. regenerate or refresh sitemaps and SEO caches;
7. purge affected WordPress, server, CDN, and browser caches;
8. verify that each old address reaches its new equivalent in one redirect.

Saving Base setup refreshes WordPress rewrite rules. If routes remain stale, save Settings → Permalinks once and then inspect any redirect or cache layer in front of WordPress.

Understand browser-detection precedence

Browser detection applies only to eligible unprefixed requests. A recognized explicit prefix always selects its own locale.

When the main-language prefix is enabled, an unprefixed first visit can follow one of two paths:

• a valid saved or browser language can produce a temporary redirect to that locale;
• otherwise the request is permanently canonicalized to the main-language prefix.

Test this interaction before launch. A normal browser may retain a previous language preference, so use a private session when verifying first-visit behavior.

Verify the chosen policy

Check at least:

• the homepage with and without the expected prefix;
• one post or page in every configured language;
• one taxonomy or archive route;
• selector links from the main and an additional language;
• canonical and hreflang output;
• browser detection with matching and non-matching language preferences;
• old URLs and redirect status codes;
• cache separation between locale paths.

The best policy is the one applied consistently. Once public URLs exist, changing it requires the same care as any other site-wide permalink migration.

Read Understand URL language prefixes for the rules used to generate each prefix.