The purpose of the present study was to examine the relationship between reading literacy and age in an adult population aged 25 to 65 in Nordic countries using PIAAC 2012 data. More specifically, the study examined to what extent variations in the literacy proficiency of adults are explained by age and the recentness of qualifications when variables related to education, occupation, and skill use are controlled. The statistical method was regression analysis. The recentness of education explained only a part of the performance gap between the oldest adults and others. The significance of the length and scope of initial education in developing literacy proficiency overall, is difficult to compensate. There were insignificant differences between the Nordic countries.