PostNL Address Validation API

What PostNL Address Validation API is

PostNL Address Validation API checks address details entered in a webshop or CRM, including addresses in the Netherlands and abroad. It can offer matching addresses while a customer types a few letters or numbers, and supports correction, standardization, and autocomplete. Its documentation describes coverage across more than 250 countries, regions, and island groups. Responses may include a locally formatted address, its components, mailability and similarity scores, and latitude and longitude.

For Dutch validation, PostNL lists plugins for Magento, WooCommerce, ShopWare, and Opencart. The international v3 endpoint uses POST and requires an API key and application/json content type. CountryIso is required; city, postal code, street, and house number are recommended. The free Benelux check is for PostNL parcel-contract customers and requires a parcel contract. International checks start at € 0.02 per API call, with bundle pricing depending on address volume. Returning multiple addresses in one response is temporarily unavailable. PostNL invites prospective customers to request a demo or contact its data solutions team.

Who it suits

It suits webshops and CRM users seeking to validate international or Netherlands address data during entry. The free Benelux option is limited to PostNL parcel-contract customers.

Limits

The free Benelux address-check plan is for PostNL parcel-contract customers and requires a parcel contract. International validation starts at € 0.02 per check, with bundle pricing depending on address volume.

Getting started

1. Visit the PostNL developer documentation website.
2. Choose the Benelux plan if you are a PostNL parcel-contract customer, or review international check pricing.
3. For international API access, obtain an API key.
4. Send a POST request to the international v3 endpoint using application/json.
5. Include CountryIso; city, postal code, street, and house number are recommended.
6. For Dutch validation, consider a listed plugin for Magento, WooCommerce, ShopWare, or Opencart.
7. Request a demo or contact PostNL’s data solutions team for help.

Verdict

PostNL combines address suggestions with validation and normalized address details across a broad international coverage area. Check the parcel-contract condition for the free Benelux plan and note the current limit on multiple results.