This study proposes a novel index to evaluate agricultural vulnerability to climate change in coastal areas, using the case of Andhra Pradesh, the state with the second longest coastline in India. Field data was collected from more than 1000 farmers (involved in over 50 varieties of crops) in 22 riverine and coastal case study areas. Data was collected through site visits, surveys and five workshops conducted between November 2018 and June 2019. Based on the collected data sets, a new Agricultural Coastal Vulnerability Index (AGCVI) was developed and applied to the 22 sites located in two districts (Krishna and Guntur) of Coastal Andhra Pradesh. The analysis revealed that the areas with three crop seasons (Kharif, Rabi and Zaid) per year are highly vulnerable to climate change. On the other hand, sites with one crop season (Kharif) per annum are the least vulnerable to climate change. Moreover, grains (particularly rice), flowers and fruit crops are more susceptible to climate change and its induced impacts. Rice is no longer a profitable crop in the case study areas partly as a result of unfavourable weather conditions, inadequate insurance provision and lack of government support for farmers. Cumulatively, all these circumstances impact farmers’ incomes and socio-cultural practices: this is leading to a marriage crisis, with a reduction in the desirability of matrimony to farmers. These findings provide valuable information that can support climate and agriculture policies, as well as sustainable cropping patterns among farmers’ communities in coastal areas of India in the future.