InStijl Postcode Checker has an (API) connection with Postcode.eu. A subscription to Postcode.eu is therefore required. You can easily request this through this app, or create an account yourself at www.postcode.eu. If you have InStijl Media request a subscription, all you have to do is fill in the company details and we will set up the rest for you! If you request a subscription from Postcode.eu yourself, all you have to do is fill in the API Keys.