Postal Code 3603 – Maarssen, Utrecht

Postal Code 3603 for Maarssen, Utrecht is part of the Netherlands postal code system, which uses an alphanumeric code of 6 (+ space) characters (e.g. 1012 JS). Addresses here are organised as Province → Municipality → Locality.

Administratively it is recorded in Utrecht within Netherlands. Postal codes are assigned by delivery route rather than by administrative boundary, so a single code can cover more than one locality and a locality can fall under several codes.

No building-level records are held for this code in the imported dataset, so only the code and its location details are shown. The absence of records does not mean the postal code is unused.

Couriers, e-commerce checkout forms and address autocomplete tools all rely on the postal code to route mail and to check that a stated address matches the code. Because a postal code identifies a delivery area rather than a single building, two addresses that share the same code can still be some distance apart.

Always write Netherlands Postal Code in full when completing a form, including any leading zero. Enter a valid Dutch postal code, e.g. 1012 JS. Data source: a third-party open dataset. This is a reference snapshot, not a live government feed, so confirm the code with the sender, carrier or postal authority before relying on it.