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	3,615	28,346,738	11.3
Marshall Islands	3,071	19,232,226	9.0
Panama	3,044	20,450,587	10.4
Malta	1,648	16,252,531	12.6
Singapore	1,403	11,652,339	10.3
Hong Kong	1,236	11,529,854	9.2
Bahamas	992	10,358,167	13.3
Cyprus	647	5,710,955	18.6
Norway	637	4,931,078	19.8
Portugal	619	6,328,934	23.8
Antigua and Barbuda	588	2,834,212	41.7
Greece	514	5,846,658	7.0
Netherlands	412	3,023,540	45.7
Italy	383	7,485,683	37.3
Denmark	372	6,738,246	11.2
United Kingdom	303	3,238,918	12.2
China	249	1,282,932	9.6
Barbados	195	534,333	13.5
Türkiye	194	1,552,490	26.9
Russia	171	428,744	38.7
France	153	3,274,907	19.3
Isle of Man	151	936,665	13.6
Germany	133	2,348,613	19.5
Bermuda	128	3,080,189	18.2
Cayman Islands	118	770,467	14.1
Japan	102	1,015,359	43.8
Finland	89	1,976,721	59.1
South Korea	88	494,736	41.7
Philippines	85	257,407	9.0
Gibraltar	85	455,405	38.6
Sweden	81	1,421,068	32.3
Belgium	77	555,432	9.2
Spain	73	1,790,073	178.2
Palau	70	155,819	19.4
United States	70	819,627	33.0
Saudi Arabia	61	492,125	8.6
Saint Kitts and Nevis	55	120,831	20.2
Canada	48	202,889	37.5
India	48	204,844	8.5
Belize	46	83,152	15.1
Faroe Islands	37	298,969	56.2
Croatia	35	222,892	9.2
Sierra Leone	34	129,127	15.8
Comoros	30	54,499	24.8
Indonesia	29	190,321	21.0
Thailand	28	72,588	10.6
Vanuatu	28	52,516	25.4
Cook Islands	28	44,040	22.4
Kuwait	27	85,923	10.6
Luxembourg	27	247,027	17.5
Saint Vincent and the Grenadines	27	72,786	21.2
Switzerland	26	107,733	7.7
Latvia	23	109,373	43.1
Egypt	23	93,454	12.9
Algeria	23	230,200	48.9
Bangladesh	22	74,766	7.9
Brazil	20	141,157	9.0
Lithuania	20	388,080	74.6
Ireland	19	90,957	21.0
Curaçao	19	105,430	80.4
Malaysia	18	202,149	14.9
Iran	17	117,489	40.5
San Marino	15	36,858	15.9
Tuvalu	14	43,208	28.6
Morocco	14	103,010	46.0
Estonia	11	247,830	81.4
Lebanon	11	9,862	390.0
Togo	10	15,051	32.9
Libya	10	54,910	20.7

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.