Recent economic diversifications of Kazakhstan from over-reliance on the extraction of natural resources are mainly based on increasing the quality of human capital by building a knowledge-based economy as an instrument for long-term sustainable development. In this regard, the paper explores the level of cognitive skills of the adult population in Kazakhstan and their associations with important life outcomes. Research is based on one of the prominent studies in adult literacy — The Programme for the International Assessment of Adult Competencies (PIAAC), and revealed that the performance of Kazakhstanis in information-processing skills is below the average; smaller differences in competencies between the top and bottom performers, which indicates small inequalities in skills acquisition; and a low level of variance between adults with tertiary and secondary education, demonstrating the low education quality. Multiple linear regression of the research indicates that the educational attainment of the population has the highest association with all three information-processing skills, while labor force participation negatively affects the growth of literacy, numeracy, and problem-solving in technology-rich environment (PS-TRE) skills. The main recommendations of the paper are to profoundly transform social institutions, enhance national educational quality, and exercise continuous learning in the country.