Exhibit 21 Subsidiaries of Oregon Trail Financial Corp. Exhibit 21 Subsidiaries of the Registrant Parent Oregon Trail Financial Corp. Percentage Jurisdiction or Subsidiaries (a) of Ownership State of Incorporation - ---------------- ------------ ---------------------- Pioneer Bank, A Federal Savings Bank (1) 100% United States Pioneer Development Corporation (2) 100% Oregon Pioneer Bank Investment Corporation (2) 100% Oregon - ---------- (1) Upon consummation of the Conversion, Pioneer Bank, A Federal Savings Bank will become a wholly-owned subsidiary of the Registrant. (2) This corporation is a wholly owned subsidiary of Pioneer Bank, A Federal Savings Bank.