Are digital stamps invoiced straight after they have been created? Yes, digital stamps are invoiced straight after they have been created. Gerelateerde vragen Why is there no discount offered on PostNL's letterbox parcel and digital postage stamp? Does an unfranked label have a Track & Trace option? How long is the digital stamp valid for? How do I add my own logo or text to a digital stamp? Why is there no Track & Trace code for the digital stamp?