diff --git a/PortfolioJournal/Views/Dashboard/MonthlyCheckInView.swift b/PortfolioJournal/Views/Dashboard/MonthlyCheckInView.swift
index 9b715f1..d362c59 100644
--- a/PortfolioJournal/Views/Dashboard/MonthlyCheckInView.swift
+++ b/PortfolioJournal/Views/Dashboard/MonthlyCheckInView.swift
@@ -31,12 +31,10 @@ struct MonthlyCheckInView: View {
     }
 
     private var checkInProgress: Double {
-        guard let nextDate = nextCheckInDate,
-              let periodStart = Calendar.current.date(
-                byAdding: .month,
-                value: -checkInIntervalMonths,
-                to: nextDate
-              ) else { return 1 }
+        guard let nextDate = nextCheckInDate else { return 1 }
+        // Period starts at the first day of the month that opens the interval.
+        // e.g. monthly → Feb 1; quarterly → Jan 1 (3 months ending Mar 31)
+        let periodStart = nextDate.adding(months: -(checkInIntervalMonths - 1)).startOfMonth
         let totalDays = Double(max(1, periodStart.startOfDay.daysBetween(nextDate.startOfDay)))
         let elapsedDays = Double(max(0, periodStart.startOfDay.daysBetween(Date().startOfDay)))
         return min(elapsedDays / totalDays, 1)