West Attica
West Attica is one of the regional units of Greece. It is part of the region of Attica. The regional unit covers the western part of the agglomeration of Athens, and the area to its west.
Administration
The regional unit West Attica is subdivided into 5 municipalities. These are :With respect to parliamentary elections West Attica belongs to the electoral district of Attica.
Prefecture
As a part of the 2011 Kallikratis government reform, the regional unit West Attica was created out of the former prefecture West Attica. The prefecture had the same territory as the present regional unit. At the same time, the municipalities were reorganised, according to the table below.| New municipality | Old municipalities | Seat |
| Aspropyrgos | Aspropyrgos | Aspropyrgos |
| Elefsina | Elefsina | Elefsina |
| Elefsina | Magoula | Elefsina |
| Fyli | Fyli | Ano Liosia |
| Fyli | Ano Liosia | Ano Liosia |
| Fyli | Zefyri | Ano Liosia |
| Mandra-Eidyllia | Mandra | Mandra |
| Mandra-Eidyllia | Erythres | Mandra |
| Mandra-Eidyllia | Oinoi | Mandra |
| Mandra-Eidyllia | Vilia | Mandra |
| Megara | Megara | Megara |
| Megara | Nea Peramos | Megara |