diff --git a/ClosedXML/Excel/PageSetup/XLPageSetup.cs b/ClosedXML/Excel/PageSetup/XLPageSetup.cs
index 9aca46d..8fdc197 100644
--- a/ClosedXML/Excel/PageSetup/XLPageSetup.cs
+++ b/ClosedXML/Excel/PageSetup/XLPageSetup.cs
@@ -192,11 +192,13 @@
         {
             if (!RowBreaks.Contains(row))
                 RowBreaks.Add(row);
+            RowBreaks.Sort();
         }
         public void AddVerticalPageBreak(Int32 column)
         {
             if (!ColumnBreaks.Contains(column))
                 ColumnBreaks.Add(column);
+            ColumnBreaks.Sort();
         }
 
         //public void SetPageBreak(IXLRange range, XLPageBreakLocations breakLocation)
diff --git a/ClosedXML_Tests/Excel/PageSetup/PageBreaksTests.cs b/ClosedXML_Tests/Excel/PageSetup/PageBreaksTests.cs
index 16b3614..04d7464 100644
--- a/ClosedXML_Tests/Excel/PageSetup/PageBreaksTests.cs
+++ b/ClosedXML_Tests/Excel/PageSetup/PageBreaksTests.cs
@@ -8,6 +8,30 @@
     public class PageBreaksTests
     {
         [Test]
+        public void RowBreaksShouldBeSorted()
+        {
+            var wb = new XLWorkbook();
+            IXLWorksheet sheet = wb.AddWorksheet("Sheet1");
+
+            sheet.PageSetup.AddHorizontalPageBreak(10); 
+            sheet.PageSetup.AddHorizontalPageBreak(12); 
+            sheet.PageSetup.AddHorizontalPageBreak(5);
+            Assert.That(sheet.PageSetup.RowBreaks, Is.EqualTo(new[] { 5, 10, 12 }));
+        }        
+
+        [Test]
+        public void ColumnBreaksShouldBeSorted()
+        {
+            var wb = new XLWorkbook();
+            IXLWorksheet sheet = wb.AddWorksheet("Sheet1");
+
+            sheet.PageSetup.AddVerticalPageBreak(10);
+            sheet.PageSetup.AddVerticalPageBreak(12);
+            sheet.PageSetup.AddVerticalPageBreak(5);
+            Assert.That(sheet.PageSetup.ColumnBreaks, Is.EqualTo(new[] { 5, 10, 12 }));
+        }        
+
+        [Test]
         public void RowBreaksShiftWhenInsertedRowAbove()
         {
             var wb = new XLWorkbook();