Liste der nach Einwohnerzahl bedeutendsten Orte (max. 300 Orte) in Kocaeli, mit Links zu den Ortsdetails
| Ort | Einwohnerzahl | Landesregion | |
|---|---|---|---|
| Akçaova | 0 | Kocaeli | |
| Akmeşe | 0 | Kocaeli | |
| Arslanbey | 3927 | Kocaeli | |
| Bahçecik | 8648 | Kocaeli | |
| Balaban | 1326 | Kocaeli | |
| Balçık | 1102 | Kocaeli | |
| Büyükderbent | 0 | Kocaeli | |
| Çayırova | 0 | Kocaeli | |
| Darıca | 0 | Kocaeli | |
| Değirmendere | 0 | Kocaeli | |
| Derince | 125485 | Kocaeli | |
| Gebze | 281436 | Kocaeli | |
| Gölcük | 56189 | Kocaeli | |
| Halıdere | 3073 | Kocaeli | |
| Hereke | 0 | Kocaeli | |
| İhsaniye | 9186 | Kocaeli | |
| İzmit | 196571 | Kocaeli | |
| Kandıra | 13805 | Kocaeli | |
| Karamürsel | 30525 | Kocaeli | |
| Karşıyaka | 3221 | Kocaeli | |
| Kaymas | 0 | Kocaeli | |
| Kefken | 1520 | Kocaeli | |
| Körfez | 90580 | Kocaeli | |
| Köseköy | 9200 | Kocaeli | |
| Kullar | 8820 | Kocaeli | |
| Mollafeneri | 0 | Kocaeli | |
| Tavşancıl | 3593 | Kocaeli | |
| Tavşanlı | 2073 | Kocaeli | |
| Ulaşlı | 2630 | Kocaeli | |
| Yalakdere | 2015 | Kocaeli | |
| Yuvacık | 7338 | Kocaeli |