St. Stephan, Baden, Gothic parish church in Baden, Austria

St. Stephan is a Catholic parish church on the eastern edge of Baden's old town, measuring 55 m long and 20 m wide. Its 67 m tower carries a Baroque onion dome added in 1697. The nave, built in the second half of the 15th century, incorporates Romanesque outer walls, and a west tower above the main portal was reshaped in 1827.

The present church was begun around 1400, when a Gothic choir was built over a Romanesque apse; the nave and main steeple followed in the second half of the 15th century. Badly damaged in the Ottoman wars, it received its onion dome in 1697 and a Baroque interior. In 1880 the interior was reworked to revive Gothic elements, and the high altar was replaced in 1893.

The parish takes its name from St. Stephen, patron saint of Passau, reflecting centuries under that diocese. The church holds five bells, including the 1832 Great Bell and the 1764 Litany Bell, which survived both world wars. A 2012 postage stamp marked the 700th anniversary of the parish.

St. Stephan stands at the eastern edge of Baden's old town on the Pfarrplatz, its 67-metre tower with the baroque onion dome visible from afar. The parish belongs to the Archdiocese of Vienna and today counts around 6,000 Catholics. The church is an active place of worship, so time a visit outside services; the tower houses a former sexton's flat and a paraments chamber.

The motet Ave verum corpus, K. 618, was written by Mozart in June 1791 for his friend Anton Stoll, the choral conductor at St. Stephan, and was premiered by the church choir here rather than by Mozart himself. Musicologist Christoph Wolff places the first performance around the feast of Corpus Christi, 22 June 1791.