Of the rest of the land, 9.6% is settled (buildings or roads) and the remainder (1.6%) is non-productive (rivers or lakes).

It consists of the village of Andwil and the hamlets of Oberarnegg, Fronackeren and Hinterberg, as well as the more distant Andwilermoos.

The blazon of the municipal coat of arms is Argent a Deer Head couped Gules.

Of the foreign population, (as of 2000[update]), 11 are from Germany, 16 are from Italy, 47 are from ex-Yugoslavia, 8 are from Austria, 8 are from Turkey, and 24 are from another country.

[8] The age distribution, as of 2000[update], in Andwil is; 237 children or 15.2% of the population are between 0 and 9 years old and 220 teenagers or 14.1% are between 10 and 19.

[4] Out of the total population in Andwil, as of 2000[update], the highest education level completed by 301 people (19.3% of the population) was Primary, while 609 (39.1%) have completed Secondary, 169 (10.9%) have attended a Tertiary school, and 50 (3.2%) are not in school.

[8] The historical population is given in the following table:[3] The Kulturlandschaft Matten/Wilen/Zinggenhueb (Cultural region: Matten/Wilen/Zinggenhueb), which is shared between Andwil and Gossau, is designated as part of the Inventory of Swiss Heritage Sites.

[10] From the 2000 census[update], 1,053 or 67.6% are Roman Catholic, while 328 or 21.1% belonged to the Swiss Reformed Church.