Fail was a Portuguese parish in the municipality of Viseu, with 6.92 km<sup>2</sup> (2.7 sq mi) and 664 inhabitants (2011). Density: 96 inhabitants / km<sup>2</sup> (245/sq mi).
In 2013 Law No 11-A / 2013 was changed and Fail was reclassified into the Union of Parishes based in .