Köseköy Postal Codes: 41250 | Kartepe, Kocaeli, Marmara
The Postal Codes (Posta kodları) for Köseköy is 41250 in Kartepe, Kocaeli, Marmara, Kartepe, Turkey. The table below lists Postal Codes and postcodes for places within Köseköy.
Postal Codes for Places in Köseköy
Showing 4 places in Köseköy. Last verified with official records on April 25, 2026.
| Dumlupınar mah. | |
| Fatih Sultan Mehmet mah. | |
| İstasyon mah. | |
| Köseköy mah. |
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Sample Address Format for Köseköy
[Sender Street Address]
[City, ZIP]
[Country]
Street Address / PO Box
Köseköy, Kartepe, Kocaeli, Marmara, 41250
TURKEY
Köseköy on the Map
The map above highlights the geographic boundaries of the Köseköy towns in Turkey.
Köseköy Quick Facts
| Country | Turkey (TR) |
|---|---|
| Administrative Path | Turkey → Marmara → Kocaeli → Kartepe |
| Postal Code | 41250 |
| Regions | Marmara |
| Provinces | Kocaeli |
| Districts | Kartepe |
| ISO Codes | TR / TUR / 792 |
| Top-level domain (ccTLD) | .tr |
| Coordinates | 40.748898, 30.006212 |
| Places | 4 |
What to Know About Köseköy
Key Facts
Köseköy is a neighborhood (mahalle) within the Kartepe district of Kocaeli Province, located in the Marmara Region of northwestern Turkey. Situated in the eastern part of the Kartepe district, Köseköy lies approximately 15 kilometers northeast of the provincial capital, İzmit, and about 90 kilometers southeast of Istanbul. This strategically positioned neighborhood serves as an important residential and commercial area within the rapidly developing Kartepe region, which is known for its natural beauty and proximity to both urban centers and recreational areas like Kartepe Mountain. While specific population figures for individual neighborhoods like Köseköy are not always readily available, Kartepe district as a whole had a population of approximately 125,000 people according to recent estimates, with Köseköy representing one of its significant residential communities. The neighborhood is administratively organized as part of Kartepe's municipal structure, which comprises multiple neighborhoods and villages under its jurisdiction. As an integral part of Turkey's postal and administrative system, Köseköy maintains its own specific postal codes that facilitate efficient mail delivery and location identification for residents and businesses operating within this growing Marmara region community.
Neighboring Regions
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- Dereköy
- Eşme
- Eşmeahmediye
- Kirazlıyalı
- Maşukiye
- Sarımeşe
- Sultaniye
- Uzunçiftlik
- Uzuntarla