La Bâtie-Montgascon is located some 20 km east by south-east of Bourgoin-Jallieu and 25 km west of La Motte-Servolex. Access to the commune is by the D1516 road from La Tour-du-Pin in the west which passes through the north of the commune and the village before continuing east to Aoste. The D1075 comes from Veyrins-Thuellin in the north and passes through the hamlet of Evrieu in the commune before continuing south-east to Les Abrets. The A43 autoroute passes through the south of the commune from west to east but has no exit in the commune. The nearest exit is Exit 10 east of the commune at Chimilin. Apart from the main village there are the hamlets of Évrieu, Avolin, Trévignieux, and Boutière. The commune is almost all farmland with a few small forests and small lakes.
In 2010 the commune had 1,771 inhabitants. The evolution of the number of inhabitants is known from the population censuses conducted in the commune since 1793. From the 21st century, a census of communes with fewer than 10,000 inhabitants is held every five years, unlike larger communes that have a sample survey every year.[Note 1]
Dr Victor Prunelle (1777-1853). Owner of the Château du Vion, his tomb is in the cemetery at La Bätie-Montgascon. A doctor and politician, he was MP for Isère, mayor of Lyon and of Vichy. He tried to quell the revolt of the Canuts in Lyon (21–24 November 1831).
Pierre Marion (1914-2000) born in La Bâtie-Montgascon. Heart surgeon, he devoted his life to the development of artificial heart valves
Gérard Nicoud had a bar-restaurant in La Bâtie-Montgascon.
Patrick Piot, professional motorcycle driver, born in 1967 at Bourgoin-Jallieu, lives in La Bâtie-Montgascon.
^At the beginning of the 21st century, the methods of identification have been modified by Law No. 2002-276 of 27 February 2002, the so-called "law of local democracy" and in particular Title V "census operations" allows, after a transitional period running from 2004 to 2008, the annual publication of the legal population of the different French administrative districts. For communes with a population greater than 10,000 inhabitants, a sample survey is conducted annually and the entire territory of these communes is taken into account at the end of the period of five years. The first "legal population" after 1999 under this new law came into force on 1 January 2009 and was based on the census of 2006.