Practitioner & industry experience.
This paper discusses the inherent tension between the usability of interfaces and tax complexity, in the Norwegian Tax Administration's (NTA) modernised prepaid tax (tax card) systems. While results indicate that the NTA has provided a usable external interface that has increased public understanding of income tax, the NTA's ambition to reduce the number of inquiries to its service centres has fallen short of its targets. Rather, service centre staff spend more time answering complex questions about income tax. This suggests that while the design has enhanced user experiences overall, the usability of the service is linked to the complexity of the tax system.