One in three adults across OECD economies lack the foundational skills to participate effectively in the labour market and society. This share has grown over the past decade, making low foundational skills one of the most persistent structural challenges facing advanced economies. Drawing on the 2023 Survey of Adult Skills (PIAAC), this report examines the scale, nature and consequences of low foundational skills in OECD countries and beyond. It analyses how the depth of skill deficits varies across countries and domains; it pinpoints the strongest predictors of low skills and uncovers distinct profiles among low-skilled populations; it highlights how these findings can inform effective policy responses. The report underscores that adults with low foundational skills are not a homogeneous group: deficits differ in severity, are distributed differently across literacy and numeracy, and reflect varying roles of migration and language background. Adults with low foundational skills face substantial and compounding disadvantages in employment, earnings, health and civic participation. Yet those who would benefit most from adult learning are consistently the least likely to engage in upskilling activities. Closing this gap requires active outreach through trusted intermediaries, provision that is contextualised and sufficiently intensive, and a sustained commitment to reaching adults whom adult learning systems have repeatedly failed to serve.
Navigating Life with Low Literacy and Numeracy
Abstract
Executive summary
Nearly one in three adults across OECD economies has low foundational skills in literacy or numeracy, according to the 2023 Survey of Adult Skills. In 11 of the 27 countries that participated in both Cycle 1 and Cycle 2 of the survey, the share of adults with low skills has increased significantly over the past decade. Only two countries recorded a reduction: Denmark and Finland.
Low foundational skills constrain employment opportunities, earnings, health, and participation in civic life. Adults with low foundational skills are around one-third less likely to be active in the labour market than those with medium proficiency. Among those in work, hourly earnings are around five dollars lower on average, with gaps exceeding ten dollars in Singapore and Switzerland. They report worse health, lower life satisfaction, and weaker trust in others and in institutions.
Two in three adults with low foundational skills perform poorly in both literacy and numeracy. However, a significant minority face deficits concentrated in one domain, highlighting the need for differentiated policy responses. In Austria, Czechia, Estonia, Latvia, Lithuania and Singapore, more than one in four adults with low skills are classified as such based on their literacy proficiency alone. In these contexts, low literacy may not reflect generalised cognitive disadvantage but rather be shaped by linguistic factors. In Canada, England (UK), Ireland, New Zealand, Sweden and the United States, the pattern reverses: numeracy deficits are more common than literacy deficits.
Most adults with low foundational skills can understand basic sentences, but what they lack is automaticity. Reading remains effortful rather than fluent, affecting confidence and engagement with written material in daily life and work. Four types of readers – fluent, effortful, surface and struggling – can be distinguished. These profiles are associated with labour market participation: among native-born adults, inactivity is ten percentage points higher among struggling readers than among fluent readers. Migrants are heavily over-represented amongst struggling readers: they account for 38% of struggling readers on average across OECD countries, rising to over 80% in Norway and Sweden.
The defining challenge of adult learning systems is the Matthew effect. Adults with the lowest skills are the least likely to engage in learning. They are held back by a combination of limited awareness of their own skill gaps, poor prior experiences of formal education, financial pressure, and employment in jobs that offer neither the time nor the encouragement to develop skills. Rates of participation in adult learning among adults with low skills are about half those of the rest of the population.
Passive adult learning provision - making courses available and advertising them - consistently fails this group. Active outreach through trusted intermediaries is the approach that works. Employers, trade unions, community organisations, healthcare providers, and social services are the channels through which hard-to-reach adults can be identified and engaged. Integrating foundational skills support into workplace settings - delivered free, interwoven with job-specific tasks, and at least partially protected from the pressures of foregone income - is among the most promising routes to scale.
Programme design also matters. Contextualised, sufficiently intensive provision consistently outperforms short, abstract instruction for adults with low skills. Sustained engagement over time is the condition for any meaningful progress. Flexible modular pathways and recognition of prior learning can make that investment compatible with the demands of family and working life.
The cross-country evidence points to four distinct country profiles, differentiated by the prevalence, depth and nature of low foundational skills, each with its own policy logic. In near-threshold countries (Canada, Czechia, Croatia, Estonia, Hungary, Ireland, Italy, Japan, Korea, Lithuania, Poland, Slovak Republic, Spain, Sweden) the population of adults with low foundational skills is clustered just below medium proficiency and relatively homogeneous. The distance to travel is short, and well-targeted short-course upskilling is a viable primary lever. In deep deficit countries, the population is, on average, further from medium proficiency and more internally diverse (Chile, Denmark, Finland, the Flemish Region (Belgium), France, Germany, Israel, the Netherlands, Portugal). Chile faces both high prevalence and deep deficits; Finland, paradoxically, belongs to the same group, not because the problem is widespread, but because the small population with low skills faces severe disadvantage. In both cases, provision must be intensive, long-duration, and inseparable from a broader educational equity agenda.
Literacy gap countries - Austria, Latvia, Norway, Singapore and Switzerland - face what is in large part a language integration challenge. Rapid and sustained language acquisition support for newly arrived migrants and language minorities is the highest-return investment available. Numeracy gap countries, including England, New Zealand and the United States, face a different kind of challenge, one that appears to originate upstream in the quality and equity of compulsory mathematics education. Remedial adult provision can help at the margins, but no adult learning system can fully compensate for what initial schooling failed to deliver.
Independent of country profile, prevention is key. High-quality early childhood education and care is the highest long-run return investment available to most governments, particularly for children from disadvantaged families. Breaking the intergenerational transmission of low skills requires both reaching adults today and ensuring the next generation enters schooling with the preparation to succeed.
Three conclusions follow from this evidence. First, the challenge of low foundational skills is large, growing, and consequential. It is a structural feature across modern economies. Second, the challenge differs fundamentally across countries and populations. Similar prevalence rates can mask entirely different problems, and generic policy responses are ill-equipped to address any of them well. Third, the principal failure of existing adult learning systems is the inability to reach those who would benefit most. Addressing this failure requires active outreach, provision designed around populations that will not reach the system on their own, and intensity matched to the scale of the deficit.
