Flag states

69 registries with at least 10 reporting vessels.

A ship's flag is the state whose register it is entered in, and whose law governs it at sea. It rarely matches where the owner sits: the largest registries by tonnage are open registers that accept vessels from any country.

Flag is not reported directly in the MRV return. It is taken from the reported port of registry where that identifies a state unambiguously, and otherwise derived from the vessel's MMSI. Each vessel page states which method was used.

Flag state	Vessels	CO₂, latest (t)	Median EEOI
Liberia	3,726	32,510,088	10.9
Marshall Islands	3,181	21,548,872	8.9
Panama	2,865	20,370,124	10.5
Malta	1,558	17,407,128	13.1
Singapore	1,294	12,603,648	10.0
Hong Kong	991	10,367,371	8.9
Bahamas	953	10,634,947	12.5
Portugal	826	8,412,488	24.1
Cyprus	588	5,993,019	15.2
Norway	584	4,800,557	17.6
Antigua and Barbuda	530	2,588,755	37.8
Netherlands	438	3,249,709	42.9
Greece	435	5,615,762	7.0
Denmark	408	6,794,634	11.0
Italy	342	7,245,908	36.6
Barbados	293	837,733	13.5
United Kingdom	203	2,641,373	11.6
China	189	1,252,642	9.5
Türkiye	182	1,279,100	27.2
Isle of Man	175	1,191,584	10.5
Russia	157	396,651	36.3
France	134	2,784,851	17.7
Bermuda	126	3,317,543	20.1
Germany	114	2,519,035	16.7
Japan	113	1,065,592	42.3
South Korea	113	793,228	33.8
Saint Kitts and Nevis	105	208,525	18.3
Cayman Islands	97	675,302	14.0
Palau	92	253,520	18.5
Sweden	79	1,384,119	32.2
Finland	77	1,701,718	56.8
Belgium	72	553,678	7.8
Spain	61	1,742,572	258.5
Saudi Arabia	60	497,116	8.2
India	51	233,728	8.5
United States	51	345,247	57.6
Sierra Leone	47	166,165	15.6
Belize	47	126,967	12.3
Philippines	42	147,784	9.0
Gibraltar	40	217,369	35.9
San Marino	39	105,758	14.3
Comoros	35	63,821	24.8
Luxembourg	33	307,927	20.4
Canada	32	128,378	38.3
Faroe Islands	32	274,318	54.2
Latvia	30	123,137	42.6
Saint Vincent and the Grenadines	30	77,776	17.7
Thailand	27	72,370	10.2
Indonesia	27	152,766	21.0
Bangladesh	27	81,796	7.5
Croatia	27	206,772	8.8
Egypt	23	110,813	13.2
Algeria	23	230,200	47.0
Vanuatu	21	38,069	25.4
Brazil	18	106,640	8.8
Ireland	18	88,395	20.5
Tuvalu	17	50,488	19.3
Iran	17	117,489	40.5
Lithuania	16	329,746	74.0
Switzerland	16	70,739	6.9
Malaysia	15	184,843	9.4
Morocco	15	116,109	42.9
Kuwait	15	140,874	10.6
Curaçao	15	136,597	132.7
Togo	11	23,522	58.3
Cook Islands	11	25,514	19.9
Guinea-Bissau	11	26,212	26.5
Vietnam	11	72,626	15.1
Estonia	10	234,548	81.4

Registries with fewer than 10 vessels are not given their own page. Flag state is taken from the reported port of registry or, failing that, derived from the vessel's MMSI; each vessel page says which.