Salinization represents a global threat to agricultural productivity and human livelihoods. Historically, much saline research has focussed on arid or semi-arid systems. The North Sea region of Europe has seen very little attention in salinity literature, however, under future climate predictions, this is likely to change. In this review, we outline the mechanisms of salinization across the North Sea region. These include the intrusion of saline groundwater, coastal flooding, irrigation and airborne salinization. The extent of each degradation process is explored for the United Kingdom, Belgium, the Netherlands, Germany, Denmark, Sweden and Norway. The potential threat of salinization across the North Sea varies in a complex and diverse manner. However, we find an overall lack of data, both of water monitoring and soil sampling, on salinity in the region. For agricultural systems in the region to adapt against future salinization risk, more extensive mapping and monitoring of salinization need to be conducted, along with the development of appropriate land management practices.