The patron of Olginate is Saint Agnes, celebrated on 21 January in the Church of Sant'Agnese.
From a religious standpoint, the Pieve di Sant'Agnese of Olginate supplanted the ancient Pieve di Garlate in 1574, whose patron was Saint Stephen the Protomartyr: his feast is still celebrated today on 26 December in the provostry church of Garlate. The town also holds the Church of San Maurizio and the curious minaret of Consonno.