Data from Volunteer Seabirds at Sea (VSAS) surveys completed in England between 2022 and 2024, funded by the Marine Natural Capital and Ecosystem Assessment (mNCEA) programme. VSAS is a citizen science programme that trains volunteers to conduct ESAS surveys on vessels of opportunity around the UK. Surveys were conducted using the European Seabirds at Sea (ESAS) method and recorded seabirds, marine mammals, large fish and turtles observed during monthly surveys on three ferry routes out of ports in England. The three routes were Penzance to St Marys, Newhaven to Dieppe and Heysham to Dublin.