Over the past decade, average literacy proficiency improved only in Denmark and Finland, remaining stable or declining in all other participating countries and economies. Numeracy outcomes are more positive, with eight countries improving their scores, led by Finland and Singapore. Most of the countries and economies that experienced skill declines saw literacy and numeracy proficiency decrease across different age groups. Widespread educational expansion did not compensate for these trends, as proficiency among tertiary-educated graduates decreased or stagnated in most countries. These findings underscore the urgent need for policymakers to focus on lifelong and life-wide learning, ensuring that education and training systems are more adaptive to evolving demands.

Declines in literacy and numeracy proficiency were particularly evident among the least educated segments of the population. This led to a widening gap in skills proficiency between highly and low-educated adults in the majority of the participating countries and economies.

Formal education plays a pivotal role in developing skills. Adults with tertiary education consistently score higher, on average, than those who left education earlier. However, higher levels of education do not always equate to better skills and knowledge.

The 2023 Survey of Adult Skills reveals that, when comparing the skills proficiency of individuals with different educational qualifications across borders, higher educational qualifications do not necessarily yield higher skills proficiency. For instance, Finnish high school graduates consistently outperform tertiary-educated adults in several countries, including Chile, Israel and Lithuania. This disparity may reflect systemic differences in the quality of education systems, as well as differences in the provision and organisation of education and lifelong learning. These differences may involve when learning takes place (e.g. childhood, youth or adulthood), where it occurs (formal, informal and non-formal), how learning is facilitated (e.g. whether there are barriers to participation) and what is learned (e.g. skills, attitudes and values).

About one-third of workers in OECD countries are mismatched for their jobs, whether in terms of their qualifications, skills or fields of study. This has significant economic and social costs, particularly if they are over-qualified. For example, adults who work in jobs that do not require their level of education receive 12% lower wages compared to peers who are in well-matched jobs. They are also four percentage points less likely to report high life satisfaction. This suggests that people in roles that do not use their qualifications can often believe their potential is wasted.

This disconnect arises partly from individuals pursuing education for which there is limited demand and the slow adaptation of training programmes to evolving industry needs. Addressing these issues requires governments to invest in recognising, rewarding and certifying skills including those acquired in the labour market, offering flexible and modular training opportunities, and improving career guidance. By aligning education and labour market demands, countries can foster a "skills-first" culture, reduce mismatches, and ensure that education investments translate into tangible economic and social benefits.

Education can reduce inequalities in society, but it can also perpetuate them, as disparities in educational attainment tend to persist across generations. In Israel, Switzerland and Hungary these effects are especially pronounced and account for at least 34 points score difference in literacy, after taking into account the respondents’ socio-demographic characteristics. The skill gap of adults from different socio-economic backgrounds is smallest in Spain, with parents’ education only accounting for a seven score point difference between adults with low and highly educated parents.