| Gorišnica Municipality | 0 | Slovenia | SI-028 |
| Gorje Municipality | 0 | Slovenia | SI-207 |
| Gornja Radgona Municipality | 0 | Slovenia | SI-029 |
| Gornji Grad Municipality | 0 | Slovenia | SI-030 |
| Gornji Petrovci Municipality | 0 | Slovenia | SI-031 |
| Gostivar Municipality | 0 | Republic of North Macedonia | MK-19 |
| Gotland County | 0 | Sweden | SE-I |
| GR | 0 | Romania | RO-GR |
| GR | 0 | Netherlands | NL-GR |
| GR | 0 | Luxembourg | LU-GR |
| GR | 0 | Switzerland | CH-GR |
| Grad Municipality | 0 | Slovenia | SI-158 |
| Gradsko Municipality | 0 | Republic of North Macedonia | MK-20 |
| Gramsh District | 0 | Albania | AL-GR |
| Grand Est | 0 | France | FR-GES |
| GRE | 0 | United Kingdom | GB-GRE |
| Greater Skopje | 0 | Republic of North Macedonia | MK-85 |
| Grevena Prefecture | 0 | Greece | GR-51 |
| Grobiņa Municipality | 0 | Latvia | LV-032 |
| Grosuplje Municipality | 0 | Slovenia | SI-032 |
| GS | 0 | Hungary | HU-GS |
| Guadeloupe | 0 | France | FR-GP |
| Guarda | 0 | Portugal | PT-09 |
| Gudja | 0 | Malta | MT-11 |
| Gulbene Municipality | 0 | Latvia | LV-033 |
| Gusinje Municipality | 0 | Montenegro | ME-22 |
| GWN | 0 | United Kingdom | GB-GWN |
| GY | 0 | Hungary | HU-GY |
| Gżira | 0 | Malta | MT-12 |
| Hajdina Municipality | 0 | Slovenia | SI-159 |
| HAL | 0 | United Kingdom | GB-HAL |
| Halland County | 0 | Sweden | SE-N |
| HAM | 0 | United Kingdom | GB-HAM |
| Ħamrun | 0 | Malta | MT-18 |
| Harju County | 0 | Estonia | EE-37 |
| Has District | 0 | Albania | AL-HA |
| Haskovo Province | 0 | Bulgaria | BG-26 |
| Hauts-de-France | 0 | France | FR-HDF |
| HAV | 0 | United Kingdom | GB-HAV |
| Havlíčkův Brod | 0 | Czech Republic | CZ-631 |
| HB | 0 | Germany | DE-HB |
| HB | 0 | Hungary | HU-HB |
| HCK | 0 | United Kingdom | GB-HCK |
| HD | 0 | Romania | RO-HD |
| HE | 0 | Germany | DE-HE |
| HE | 0 | Hungary | HU-HE |
| Hedmark | 0 | Norway | NO-04 |
| HEF | 0 | United Kingdom | GB-HEF |
| Herzegovina-Neretva Canton | 0 | Bosnia and Herzegovina | BA-07 |
| HH | 0 | Germany | DE-HH |
| HI | 0 | Moldova | MD-HI |
| HI | 4 | United States | US-HI |
| Hiiu County | 0 | Estonia | EE-39 |
| HIL | 0 | United Kingdom | GB-HIL |
| HLD | 0 | United Kingdom | GB-HLD |
| HM | 0 | Belarus | BY-HM |
| HMF | 0 | United Kingdom | GB-HMF |
| HNS | 0 | United Kingdom | GB-HNS |
| HO | 0 | Belarus | BY-HO |
| Hoče–Slivnica Municipality | 0 | Slovenia | SI-160 |
| Hodonín | 0 | Czech Republic | CZ-645 |
| Hodoš Municipality | 0 | Slovenia | SI-161 |
| Hordaland | 0 | Norway | NO-12 |
| Horjul Municipality | 0 | Slovenia | SI-162 |
| HPL | 0 | United Kingdom | GB-HPL |
| HR | 0 | Romania | RO-HR |
| HR | 0 | Belarus | BY-HR |
| Hradec Králové | 0 | Czech Republic | CZ-521 |
| Hrastnik Municipality | 0 | Slovenia | SI-034 |
| Hrpelje–Kozina Municipality | 0 | Slovenia | SI-035 |
| HRT | 0 | United Kingdom | GB-HRT |
| HRW | 0 | United Kingdom | GB-HRW |
| HRY | 0 | United Kingdom | GB-HRY |
| HV | 0 | Hungary | HU-HV |
| IA | 0 | Moldova | MD-IA |
| IA | 6 | United States | US-IA |
| ID | 6 | United States | US-ID |
| Ida-Viru County | 0 | Estonia | EE-44 |
| Idrija Municipality | 0 | Slovenia | SI-036 |
| Iecava Municipality | 0 | Latvia | LV-034 |
| IF | 0 | Romania | RO-IF |
| Ig Municipality | 0 | Slovenia | SI-037 |
| Ignalina District Municipality | 0 | Lithuania | LT-09 |
| Iklin | 0 | Malta | MT-19 |
| Ikšķile Municipality | 0 | Latvia | LV-035 |
| IL | 0 | Romania | RO-IL |
| IL | 6.25 | United States | US-IL |
| Île-de-France | 0 | France | FR-IDF |
| Ilinden Municipality | 0 | Republic of North Macedonia | MK-34 |
| Ilūkste Municipality | 0 | Latvia | LV-036 |
| Imathia Regional Unit | 0 | Greece | GR-53 |
| IN | 7 | United States | US-IN |
| IN | 0 | Russia | RU-IN |
| Inčukalns Municipality | 0 | Latvia | LV-037 |
| Ioannina Regional Unit | 0 | Greece | GR-33 |
| Ionian Islands Region | 0 | Greece | GR-F |
| IOS | 0 | United Kingdom | GB-IOS |
| IOW | 0 | United Kingdom | GB-IOW |
| IRK | 0 | Russia | RU-IRK |
| IS | 0 | Romania | RO-IS |
