Grenada
18 years of age; universal
Guam
18 years of age; universal; US citizens, but do not vote in US
presidential elections
Guatemala
18 years of age; universal (active duty members of the
armed forces may not vote and are restricted to their barracks on
election day)
Guernsey
18 years of age; universal
Guinea
18 years of age; universal
Guinea-Bissau
18 years of age; universal
Guyana
18 years of age; universal
Haiti
18 years of age; universal
Holy See (Vatican City)
limited to cardinals less than 80 years old
Honduras
18 years of age; universal and compulsory