National variants

Every national activity classification in the EU is bound by the same contract with NACE: the first four digits are, and must remain, a NACE class. National statistical institutes may extend the fourth-level class with a fifth digit (or letter), rename classes into the local language, and add explanatory notes tuned to the local economy — but they may not create a new four-digit code that does not exist in NACE, and they may not reuse an existing NACE code for a different activity.

This is what makes cross-border translation possible without a translation table for every pair of countries: the shared four-digit backbone is the anchor.

· France — NAF (Nomenclature d'activités française). Adds a trailing letter to the four-digit NACE class (6201Z, 4711D). Maintained by INSEE.

· Germany — WZ (Klassifikation der Wirtschaftszweige). Adds a numeric fifth digit separated by a dot (62.01.0, 47.11.1). Maintained by DESTATIS.

· Portugal — CAE (Classificação Portuguesa das Actividades Económicas), currently CAE-Rev. 4. Compresses to a five-digit numeric code (62010, 47111). Maintained by INE.

· Netherlands — SBI (Standaard Bedrijfsindeling). Adds a decimal fifth digit (62.01, 47.11.1). Maintained by CBS.

· Italy — ATECO. Adds a numeric fifth digit (62.01.00 through 62.01.99). Maintained by ISTAT.

· Spain — CNAE (Clasificación Nacional de Actividades Económicas). Four-digit numeric extension (6201). Maintained by INE.

· Slovenia — SKD (Standardna klasifikacija dejavnosti). Adds a numeric fifth digit. Maintained by SURS.

There are many more — every EU member state, plus several EEA and candidate countries, maintain their own variant.

In practice, a company operating across borders — or a data vendor consolidating data from several countries — needs to move fluently between these systems. The rule is simple: to translate any national code into any other national code, drop to the shared four-digit NACE anchor first, then fan out into the target country's fifth-digit subclasses.

This is exactly what NACEBridge does under the hood, and it is what the /convert and /cousins routes expose as a single API call.