Greece tops the list of countries and territories with the largest owned fleets, according to a Review of Maritime Transport 2012, issued by the United Nations Conference on Trade and Development (UNCTAD). The other countries completing the top-five list are Japan, Germany, China and the Republic of Korea.

Greece has the fourth largest fleet in terms of number of vessels (3,321), but the volume of the fleet is primarily measured in terms of deadweight tonnage, in which Greece comes first (224,051,881 dwt), granting it thus the largest estimated share in the transport of global seaborne trade (16,10% market share).

Although this percentage has dwindled, compared to previous years (16,17% in 2010, 16,81% in 2008), there is still a considerable gap separating it from Japan's (at second place with a 15,64% market share).