Date of accession
1949
1952
1955
1982
1990
Formally
invited to join
1999
2004
2009
2017
2020
Not on the map
US
Canada
Finland
Sweden
Russia
Estonia
Latvia
Lithuania
Czech
Rep
Poland
Ukraine
Hungary
Slovakia
Romania
Slovenia
Bulgaria
Croatia
Montenegro
North Macedonia
Albania
Date of
accession
1949
1952
1955
1982
1990
1999
2004
2009
2017
2020
Formally invited to join
Not on the map
US
Canada
Iceland
Finland
Norway
Sweden
Estonia
Russia
UK
Latvia
Denmark
Lithuania
Germany
Poland
Ukraine
Netherlands,
Belgium, Lux
Slovakia
Czech Rep
France
Slovenia
Hungary
Romania
Croatia
Bulgaria
Portugal
Turkey
Spain
Italy
Greece
Montenegro
Albania
North Macedonia