The 10 Least Sustainable Countries In The World

Each year, the Environmental Performance Index (EPI) releases its report. This story focuses on the 2026 edition and, with a few exceptions, draws primarily on that report. It examines the bottom 10 of the 177 nations ranked.

The scores are built from metrics covering environmental health and protection. The data are divided into 12 categories, including air quality, forests, fisheries, and climate, and draw on information from international agreements. The index also leans heavily on the OECD handbook, which was created to guide the construction of composite indicators from data and policy measures.

The ratings rest on three main pillars:

1. Ecosystem health (45%), which evaluates wildlife habitat, forests, fisheries, and farming.
2. Climate change (30%), which is driven largely by greenhouse gas emissions and whether they are rising or falling.
3. Human health (25%), which is built from data on air pollution, drinking water, and sanitation.

In the authors’ words, “These indicators provide a gauge at a national scale of how close countries are to established environmental policy targets.” They hope the index will help governments set better policy on sustainability practices, laws, and regulations.

Scores can range from 0 to 100, with 100 being the best. In practice, the top score belongs to Estonia at 74.79, followed closely by Luxembourg at 74.24.

The 10 nations at the bottom of the list tend to share several traits. One is unhealthy air and water, both of which cause major health problems; India and Laos score particularly poorly on this measure. Another is rising greenhouse gas emissions in most of these countries. India illustrates the trend: according to World Population Review, it ranks second only to China in coal consumption. Finally, poor ecosystem health drags down scores, owing to farm pollution runoff, overfishing, and a lack of government protection for land.

These are the 10 least sustainable countries in the world:

Country	Ranking	EPI score	10-year change
Indonesia	168	26.24	+1.82
Mauritania	169	25.34	+0.22
Liberia	170	25.27	+2.32
Maldives	171	25.06	+4.54
Burundi	172	24.39	+1.96
Viet Nam	173	23.82	−1.94
Mali	174	23.56	+1.86
Bangladesh	175	23.46	+4.41
India	176	22.46	+7.47
Laos	177	21.78	+3.63

Source: Yale EPI 2026