Șag is a commune in Timiș County, Romania. It is composed of a single village, Șag; Parța village broke off as a separate commune in 2004.

Timiș is a county (județ) of western Romania on the border with Hungary and Serbia, in the historical region of Banat, with the county seat at Timișoara. It is the westernmost and the largest county in Romania in terms of land area. The county is also part of the Danube–Criș–Mureș–Tisa Euroregion.