Background: The COVID-19 pandemic has brought an unprecedented threat to the dairy sector and it faced disruptions primarily due to the perishable nature of dairy products and the breakdown of the supply chain. In this study, an attempt was made to quantify the economic losses faced by the members and non-members of the Dairy cooperative societies (DCS). Methods: The study was conducted in Howrah, Nadia and N-24 Parganas districts of West Bengal, India. A multistage sampling scheme was employed to select dairy farmers from each district. A total of 90 DCS member and 90 non-member dairy farmers were studied. The data collected from the farmers covered the three periods of the first wave of the COVID-19 pandemic i.e. pre-lockdown (January 01 2020 to March 23 2020), lockdown (March 24 2020 to May 31 2020) and post-lockdown period (June 01 2020 to December 31 2020). Result: The total cost of milk production increased significantly by around 1 to 3% for DCS members and around 1 to 5% for non-members. The net returns from dairying were reduced significantly for both DCS members and non-members but it was more for non-members (lockdown: 80 to 90%, post-lockdown: 32 to 60%) than the DCS members (lockdown: 10 to 18%, post-lockdown: 7 to 15%).