Background: This study explored the credibility of Swedish third-grade students' self-assessments of their reading achievement by relating those assessments to two different criteria-teachers' judgments and students' reading test scores. Student gender and socioeconomic status (SES) were introduced to determine to what extent, if any, these variables were associated with the accuracy of the selfassessments once students' attitudes toward reading had been controlled for. Methods: The data, drawn from the Swedish participation in the 2001 iteration of the Progress in International Reading Literacy Study (PIRLS), conducted by the International Association for the Evaluation of Educational Achievement (IEA), included information obtained from students (N = 5,271) and teachers (N = 351). The main method of analysis was two-level structural equation modeling (SEM) with latent variables. Results: The magnitude of the correlation between student self-assessments and teacher judgments/test scores was similar and amounted to about 0.6. The relationship between teachers' judgments and students' test scores was slightly higher. Neither gender nor SES seemed to be significantly related to the selfassessments, indicating that the students assessed themselves in a fairly equal manner across groups. Conclusions: The findings demonstrate that, despite their young age, third-graders' self-assessment of their reading literacy skills can be considered as fairly reliable indicators of those skills. In Sweden, the fact that Grade 3 students and their teachers have spent almost three years together in school may contribute to a shared understanding of what literacy knowledge and skills are important.