The wellbeing of mountain communities is determined by the availability and accessibility of ecosystem goods and services. We assessed the relationship between forest quality and wellbeing of local communities of Nanda Devi Biosphere Reserve (NDBR) in the Upper Ganga River Basin, Western Himalayas, India. We used 14 relevant Sustainable Development Goals of the United Nations as indicators to assess wellbeing. Data on these indicators were collected in 22 villages that were selected based on secondary demographic information, remoteness, and the state of the forest resources, which we classified into degraded and less-degraded. Semi-structured questionnaire-based interviews were conducted in randomly selected households (n = 764). The households located close to forests scored higher on wellbeing indicators than the households located further away from forests as they have better accessibility to forest resources and freshwater, which provides alternatives to market and agricultural products. Households with access to less-degraded resources also had access to wild fruits, vegetables, and medicinal plants adding to their food and health security. Our study found that the combination of climate change, declining forest resources, and the expansion of the market-based economy is leading to shifts in traditional cropping patterns and hence the nutritional status and forest use patterns of local people, making them vulnerable to diseases and hunger. Accessibility to an intact forest patch near a village contributes to the wellbeing of people and increases their resilience in the face of climate change and the changes dictated by the market forces.