Municipalities
| Municipality | Population (2025) | km² | per km² |
|---|---|---|---|
| Bilbao ★ | 351,124 | 40.7 | 8,627 |
| Barakaldo | 102,986 | 24.9 | 4,136 |
| Getxo | 75,752 | 13.0 | 5,827 |
| Santurtzi | 46,442 | 9.4 | 4,941 |
| Portugalete | 44,843 | – | – |
| Basauri | 40,274 | 6.0 | 6,712 |
| Leioa | 32,748 | 7.4 | 4,425 |
| Durango | 30,192 | 10.3 | 2,931 |
| Sestao | 28,512 | – | – |
| Galdakao | 24,776 | 32.7 | 758 |
| Erandio | 24,659 | 19.3 | 1,278 |
| Amorebieta-Etxano | 19,660 | 58.9 | 334 |
| Mungia | 18,129 | 41.7 | 435 |
| Gernika-Lumo | 17,129 | 9.8 | 1,748 |
| Bermeo | 17,038 | 32.7 | 521 |
| Ermua | 15,516 | 4.9 | 3,167 |
| Sopela | 15,048 | 8.0 | 1,881 |
| Etxebarri | 12,038 | – | – |
| Arrigorriaga | 11,939 | 18.8 | 635 |
| Valle de Trápaga-Trapagaran | 11,797 | 12.9 | 914 |
| Abanto y Ciérvana-Abanto Zierbena | 9,379 | 16.0 | 586 |
| Ortuella | 8,735 | 8.3 | 1,052 |
| Zalla | 8,334 | 31.6 | 264 |
| Berango | 8,242 | 8.2 | 1,005 |
| Ondarroa | 8,060 | 4.8 | 1,679 |
| Abadiño | 7,768 | 38.5 | 202 |
| Balmaseda | 7,718 | 22.5 | 343 |
| Muskiz | 7,465 | 19.8 | 377 |
| Derio | 7,294 | 10.6 | 688 |
| Elorrio | 7,277 | 38.2 | 190 |
| Lekeitio | 7,211 | – | – |
| Güeñes | 6,817 | 42.5 | 160 |
| Urduliz | 6,128 | 7.9 | 776 |
| Gorliz | 6,034 | 8.9 | 678 |
| Markina-Xemein | 5,089 | 44.4 | 115 |
★ = municipality with a dedicated guide. Municipalities with at least 5,000 inhabitants are listed.