How many digits is a French postal code?

A French code postal is always exactly five digits. The first two digits normally indicate the département; the last three identify the delivery office or area.

How are Corsica and the DOM-TOM handled?

Corsica uses 20xxx, split into 2A (Corse-du-Sud) and 2B (Haute-Corse). The overseas départements and territories use 97x and 98x prefixes (for example 971 Guadeloupe, 972 Martinique, 974 Réunion, 987 French Polynesia).

Does the postal code always match the département number?

Usually, but not always. Some communes have a postal code whose first two digits differ from their administrative département, and Paris (75), the inner suburbs and Cedex codes have their own conventions. Treat the mapping as a strong hint.

Does a valid format mean the address is deliverable?

No. This tool checks the format and prefix only. A well-formed code can still be unassigned, so confirm deliverability with La Poste if it matters.

Is my postal code sent anywhere?

No. Validation and the lookup run entirely in your browser. Nothing leaves your device.

France Postal Code Validator

A French code postal is the 5-digit postal code used to route mail across metropolitan France and its overseas territories. The first two digits normally signal the département, which makes the code useful for address forms, delivery-zone logic and e-commerce checkout validation. This free tool validates the format and maps the code to its département in your browser, with full handling for Corsica and the DOM-TOM.

How it works

Strip whitespace; the input must be exactly five digits.
Read the leading digits to determine the département:
- 2A / 2B for Corsica (codes 20xxx),
- three-digit 97x / 98x prefixes for the overseas départements and territories,
- otherwise the first two digits give the metropolitan département (01–95).
Map that to the département name.

Example

Validate 75008 (Paris 8e): five digits, leading 75 → Paris. Validate 97400: the 974 prefix maps to La Réunion. 20090 maps to Corse-du-Sud (2A) by the Ajaccio range, while 20200 maps to Haute-Corse (2B).

Notes

The département mapping is an excellent heuristic but not infallible: a handful of communes carry a postal code whose prefix differs from their administrative département, and Cedex / large-volume codes follow their own rules. A valid format does not guarantee the exact code is in active use — confirm with La Poste when delivery accuracy matters. Everything runs locally in your browser.