Schmerikon sits in a German-speaking pocket of St. Gallen where Standard German (Hochdeutsch) is used on signs, in shops, and at the SBB station, while locals often speak the St. Gallen Swiss German dialect among themselves. Travelers who know a few Hochdeutsch phrases will be understood easily; attempting a friendly 'Grüezi' is appreciated.
Because Schmerikon is small, most interactions happen at the train station, the Schmerikon boat dock, lakeside restaurants, and the PostAuto bus stops connecting to Rapperswil and Uznach. A short phrasebook covering arrivals, meals, boat/train questions, and emergencies will cover nearly every visitor situation.