Lowestoft is a coastal town and civil parish in the East Suffolk district of Suffolk, England. As the most easterly UK settlement, it is 110 miles (177 km) north-east of London, 38 miles (61 km) north-east of Ipswich and 22 miles (35 km) south-east of Norwich, and the main town in its district. The estimated population in the built-up area exceeds 70,000. Its development grew with the fishing industry and as a seaside resort with wide sandy beaches. As fishing declined, oil and gas exploitation in the North Sea in the 1960s took over. While these too have declined, Lowestoft is becoming a regional centre of the renewable energy industry.

East Suffolk is a local government district in Suffolk, England. The largest town is Lowestoft, which contains Ness Point, the easternmost point of the United Kingdom. The second largest town is Felixstowe, which has the country's largest container port. On the district's south-western edge it includes parts of the Ipswich built-up area. The rest of the district is largely rural, containing many towns and villages, including several seaside resorts. Its council is based in the village of Melton. The district was formed in 2019 as a merger of the two previous districts of Suffolk Coastal and Waveney. In 2021 it had a population of 246,058. It is the most populous district in the country not to be a unitary authority.