| Disputed island | |
|---|---|
&sq=&lang=&file=File:Flat_Island.png) Flat Island | |
&sq=&lang=&file=File:Spratly_Islands_relief_location_map.svg)  Flat Island | |
| Other names | Patag Island (Philippine English) Pulo ng Patag (Filipino) Đảo Bình Nguyên (Vietnamese) 費信島 / 费信岛 Fèixìn Dǎo (Chinese) |
| Geography | |
| Location | South China Sea |
| Coordinates | 10°49′00″N 115°49′20″E / 10.81667°N 115.82222°E |
| Archipelago | Spratly Islands |
| Administration | |
| Region | IV-B - MIMAROPA |
| Province | Palawan |
| Municipality | Kalayaan |
| Claimed by | |
| Additional information | |
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Flat Island, also known as Patag Island (Filipino: Pulo ng Patag; Mandarin Chinese: 費信島/费信岛; pinyin: Fèixìn Dǎo; Vietnamese: Đảo Bình Nguyên), is the second smallest of the natural Spratly Islands. It has an area of 0.57 hectares (5,700 m2), and is about 10 kilometres (6.2 mi) north of Philippine-occupied Nanshan Island, both of which are located on the expansive but otherwise submerged Flat Island Bank in the northeast part of the of Dangerous Ground area in the South China Sea.
It is the sixth largest of the Philippine-occupied Spratly islands and is administered by the Philippines as part of Kalayaan, Palawan. The island is also claimed by the People's Republic of China, the Republic of China (Taiwan), and Vietnam.