Sankt Aegidi is a municipality in the district of Schärding, in the Austrian state of Upper Austria. It lies in the Innviertel, the north-western quarter of Upper Austria that borders Germany and was historically linked to Bavaria before passing to Austria in the early nineteenth century.
The municipality is a scattered rural community rather than a single dense town, made up of the parish village of Sankt Aegidi and a number of surrounding hamlets and farmsteads. Its name derives from Saint Giles (Aegidius), to whom the local church is dedicated. The landscape is typical of the region: rolling hills, farmland and woodland, with the Sauwald high ground rising to the north.
Sankt Aegidi is administratively part of the Schärding district, whose seat is the town of Schärding on the River Inn. Like other municipalities in the district, it is governed by an elected municipal council and mayor. The area is served by rural roads connecting it to neighbouring communities and to the wider Innviertel road network.