The middle-income trap is the idea that many economies grow quickly from low to middle income and then get stuck, unable to reach high income because the strategies that powered their early growth, such as cheap labour, moving workers off farms and copying foreign technology, run out of steam. A country in the trap can no longer compete with poorer countries on low wages, but has not yet built the skills, technology and institutions to compete with rich ones on innovation.
The term was coined by World Bank economists Indermit Gill and Homi Kharas in a 2007 report on East Asia, and the World Bank devoted its 2024 World Development Report to the subject. It uses the Bank's income groups, based on gross national income (GNI) per person; for fiscal year 2027, middle income runs from $1,176 to $14,375. The idea is closely linked to debates about emerging markets, convergence and industrial policy.
The middle-income trap in plain terms
Imagine a small bakery that grew fast by baking simple loaves cheaply, using low-paid staff and a recipe copied from a famous shop. As the bakery grows, staff demand better pay and newer bakeries undercut its prices. To keep growing it now needs its own recipes, better machines and skilled bakers, but switching takes years of investment and know-how it does not yet have.
Countries face the same squeeze. The first jump in income is relatively easy: move people from farms into factories and build basic roads and ports. The next step, competing on ideas, brands and quality, is much harder, and many countries plateau for decades at that point.
Why growth slows at middle income
- Rising wages. Once surplus rural labour has moved into industry, wages rise and low-cost manufacturing moves to poorer countries.
- Diminishing returns to capital. Building more of the same factories and roads adds less and less output; growth must come from total factor productivity (TFP).
- Skills and innovation gaps. Moving up the value chain requires human capital, research and development and firms able to adopt and adapt frontier technology.
- Institutions and incumbents. Established firms and elites may use political influence to block competition, a form of rent-seeking that keeps unproductive companies alive.
- Demographics and debt. Ageing populations, as in China and Thailand, and credit booms can cut growth before high income is reached.
How long it takes to reach high income
Growth compounds, so small differences in growth rates change the time needed to cross the high-income line. The number of years required is:
- is the number of years needed.
- is today's income per person and is the target income.
- is the annual growth rate of income per person, as a decimal.
Example: a country with income of $5,000 per person wants to reach $15,000, roughly the high-income threshold. At 5% a year growth, years. At 2% a year, years. A slowdown from 5% to 2% more than doubles the wait, which is what "being trapped" looks like in practice.
The evidence
According to the World Bank's 2024 report, 108 countries were middle income at the end of 2023, home to about three-quarters of the world's people, and only 34 middle-income economies had become high income since 1990, more than a third of them helped by joining the European Union or by newly found oil. The report found that middle-income countries typically stall at around a tenth of US income per person. Earlier work by Barry Eichengreen, Donghyun Park and Kwanho Shin found that fast-growing economies often see sharp slowdowns at middle-income levels.
Some economists question whether this is a distinct "trap". Studies have found that middle-income countries are no more likely to stagnate than low- or high-income ones, and that slow convergence is the norm at every income level. On this view the label mainly describes ordinary stagnation, not a special barrier.
Escaping the trap
South Korea, Taiwan and Singapore moved from low to high income within two generations through high saving and investment, export-oriented manufacturing, heavy investment in education and active, sometimes controversial, industrial policy. Chile, Uruguay, Poland and several other central European economies also crossed into high income. By contrast, Brazil, Mexico, South Africa and Argentina have spent long periods at middle income, and whether China and Malaysia will cross the line is widely debated.
The World Bank's 2024 report proposed a "3i" sequence: first investment; then infusion, adopting foreign technology, for example through foreign direct investment; then innovation. It stressed letting competition and creative destruction remove unproductive incumbents. Views differ on how: market-oriented economists emphasize liberalization, open trade and secure property rights, while others argue for state-led industrial policy modelled on East Asia. Most agree that productivity growth, rather than more capital alone, is decisive, a point at the heart of endogenous growth theory. Countries such as Pakistan and India, both lower-middle income, are at an earlier stage but face the same long-run question, as do resource exporters exposed to the resource curse.