The source basis for the article is the visitation protocol of the Diocese of Warmia from 1597-1598 and the visitation of the archpriesthood of Jeziorany recorded therein. It contains information about the parishes and churches of this ecclesiastical unit, part of the Diocese of Warmia, whose bishop at the time was Cardinal Andrzej Batory. It describes in detail the status of the parishes in terms of their benefice endowments, provides basic biographical data on the pastors, and provides other information related to the income of the churches of the diocese. Outlining the economic basis for the functioning of the parishes of the Lake District archpriesthood will be the subject of this article. Much of the information will supplement the knowledge of the parishes of the Jeziorany archdeaconry at the end of the 16th century. They will allow for general statements concerning the material basis of the parish structure of the Diocese of Warmia in that period.