diff --git a/src/QuikGraph/Structures/Edges/UndirectedEdge.cs b/src/QuikGraph/Structures/Edges/UndirectedEdge.cs
index bfced45ea..b4b8984aa 100644
--- a/src/QuikGraph/Structures/Edges/UndirectedEdge.cs
+++ b/src/QuikGraph/Structures/Edges/UndirectedEdge.cs
@@ -23,20 +23,28 @@ public class UndirectedEdge<TVertex> : IUndirectedEdge<TVertex>
         /// <param name="target">The target vertex.</param>
         /// <exception cref="T:System.ArgumentNullException"><paramref name="source"/> is <see langword="null"/>.</exception>
         /// <exception cref="T:System.ArgumentNullException"><paramref name="target"/> is <see langword="null"/>.</exception>
-        /// <exception cref="T:System.ArgumentException">
-        /// <paramref name="target"/> is not lower than <paramref name="source"/> when using <see cref="M:System.Collections.Generic.Comparer{T}.Default"/>.
-        /// </exception>
         public UndirectedEdge([NotNull] TVertex source, [NotNull] TVertex target)
         {
             if (source == null)
                 throw new ArgumentNullException(nameof(source));
             if (target == null)
                 throw new ArgumentNullException(nameof(target));
+
+            TVertex orderedSource;
+            TVertex orderedTarget;
             if (Comparer<TVertex>.Default.Compare(source, target) > 0)
-                throw new ArgumentException($"{nameof(source)} must be lower than {nameof(target)} in {GetType().Name}.");
+            {
+                orderedSource = target;
+                orderedTarget = source;
+            }
+            else
+            {
+                orderedSource = source;
+                orderedTarget = target;
+            }
 
-            Source = source;
-            Target = target;
+            Source = orderedSource;
+            Target = orderedTarget;
         }
 
         /// <inheritdoc />
diff --git a/tests/QuikGraph.Tests/Structures/Edges/EquatableUndirectedEdgeTests.cs b/tests/QuikGraph.Tests/Structures/Edges/EquatableUndirectedEdgeTests.cs
index 53a01dc56..168638f49 100644
--- a/tests/QuikGraph.Tests/Structures/Edges/EquatableUndirectedEdgeTests.cs
+++ b/tests/QuikGraph.Tests/Structures/Edges/EquatableUndirectedEdgeTests.cs
@@ -21,6 +21,15 @@ public void Construction()
             var v2 = new ComparableTestVertex("v2");
             CheckEdge(new EquatableUndirectedEdge<ComparableTestVertex>(v1, v2), v1, v2);
             CheckEdge(new EquatableUndirectedEdge<ComparableTestVertex>(v1, v1), v1, v1);
+
+            // Order correctly on creation
+            CheckEdge(new EquatableUndirectedEdge<int>(2, 1), 1, 2);
+
+            // Comparable
+            var comparableV1 = new ComparableTestVertex("v1");
+            var comparableV2 = new ComparableTestVertex("v2");
+            CheckEdge(new EquatableUndirectedEdge<ComparableTestVertex>(comparableV2, comparableV1), comparableV1,
+                comparableV2);
         }
 
         [Test]
@@ -28,21 +37,17 @@ public void Construction_Throws()
         {
             // ReSharper disable ObjectCreationAsStatement
             // ReSharper disable AssignNullToNotNullAttribute
-            Assert.Throws<ArgumentNullException>(() => new EquatableUndirectedEdge<TestVertex>(null, new TestVertex("v1")));
-            Assert.Throws<ArgumentNullException>(() => new EquatableUndirectedEdge<TestVertex>(new TestVertex("v1"), null));
+            Assert.Throws<ArgumentNullException>(() =>
+                new EquatableUndirectedEdge<TestVertex>(null, new TestVertex("v1")));
+            Assert.Throws<ArgumentNullException>(() =>
+                new EquatableUndirectedEdge<TestVertex>(new TestVertex("v1"), null));
             Assert.Throws<ArgumentNullException>(() => new EquatableUndirectedEdge<TestVertex>(null, null));
             // ReSharper restore AssignNullToNotNullAttribute
 
-            Assert.Throws<ArgumentException>(() => new EquatableUndirectedEdge<int>(2, 1));
-
             // Not comparable
             var v1 = new TestVertex("v1");
             var v2 = new TestVertex("v2");
             Assert.Throws<ArgumentException>(() => new EquatableUndirectedEdge<TestVertex>(v1, v2));
-
-            var comparableV1 = new ComparableTestVertex("v1");
-            var comparableV2 = new ComparableTestVertex("v2");
-            Assert.Throws<ArgumentException>(() => new EquatableUndirectedEdge<ComparableTestVertex>(comparableV2, comparableV1));
             // ReSharper restore ObjectCreationAsStatement
         }
 
diff --git a/tests/QuikGraph.Tests/Structures/Edges/TaggedUndirectedEdgeTests.cs b/tests/QuikGraph.Tests/Structures/Edges/TaggedUndirectedEdgeTests.cs
index 5ababf8d7..da31c4b21 100644
--- a/tests/QuikGraph.Tests/Structures/Edges/TaggedUndirectedEdgeTests.cs
+++ b/tests/QuikGraph.Tests/Structures/Edges/TaggedUndirectedEdgeTests.cs
@@ -25,6 +25,16 @@ public void Construction()
             CheckTaggedEdge(new TaggedUndirectedEdge<ComparableTestVertex, TestObject>(v1, v2, null), v1, v2, (TestObject)null);
             CheckTaggedEdge(new TaggedUndirectedEdge<ComparableTestVertex, TestObject>(v1, v1, null), v1, v1, (TestObject)null);
             CheckTaggedEdge(new TaggedUndirectedEdge<ComparableTestVertex, TestObject>(v1, v2, tag), v1, v2, tag);
+
+            // Order correctly on creation
+            CheckTaggedEdge(new TaggedUndirectedEdge<int, TestObject>(2, 1, null), 1, 2, (TestObject)null);
+
+            // Comparable
+            var comparableV1 = new ComparableTestVertex("v1");
+            var comparableV2 = new ComparableTestVertex("v2");
+            CheckTaggedEdge(
+                new TaggedUndirectedEdge<ComparableTestVertex, TestObject>(comparableV2, comparableV1, null),
+                comparableV1, comparableV2, (TestObject)null);
         }
 
         [Test]
@@ -32,21 +42,19 @@ public void Construction_Throws()
         {
             // ReSharper disable ObjectCreationAsStatement
             // ReSharper disable AssignNullToNotNullAttribute
-            Assert.Throws<ArgumentNullException>(() => new TaggedUndirectedEdge<TestVertex, TestObject>(null, new TestVertex("v1"), null));
-            Assert.Throws<ArgumentNullException>(() => new TaggedUndirectedEdge<TestVertex, TestObject>(new TestVertex("v1"), null, null));
-            Assert.Throws<ArgumentNullException>(() => new TaggedUndirectedEdge<TestVertex, TestObject>(null, null, null));
+            Assert.Throws<ArgumentNullException>(() =>
+                new TaggedUndirectedEdge<TestVertex, TestObject>(null, new TestVertex("v1"), null));
+            Assert.Throws<ArgumentNullException>(() =>
+                new TaggedUndirectedEdge<TestVertex, TestObject>(new TestVertex("v1"), null, null));
+            Assert.Throws<ArgumentNullException>(() =>
+                new TaggedUndirectedEdge<TestVertex, TestObject>(null, null, null));
             // ReSharper restore AssignNullToNotNullAttribute
 
-            Assert.Throws<ArgumentException>(() => new TaggedUndirectedEdge<int, TestObject>(2, 1, null));
-
             // Not comparable
             var v1 = new TestVertex("v1");
             var v2 = new TestVertex("v2");
             Assert.Throws<ArgumentException>(() => new TaggedUndirectedEdge<TestVertex, TestObject>(v1, v2, null));
 
-            var comparableV1 = new ComparableTestVertex("v1");
-            var comparableV2 = new ComparableTestVertex("v2");
-            Assert.Throws<ArgumentException>(() => new TaggedUndirectedEdge<ComparableTestVertex, TestObject>(comparableV2, comparableV1, null));
             // ReSharper restore ObjectCreationAsStatement
         }
 
diff --git a/tests/QuikGraph.Tests/Structures/Edges/UndirectedEdgeTests.cs b/tests/QuikGraph.Tests/Structures/Edges/UndirectedEdgeTests.cs
index cef15d3b1..1df33593a 100644
--- a/tests/QuikGraph.Tests/Structures/Edges/UndirectedEdgeTests.cs
+++ b/tests/QuikGraph.Tests/Structures/Edges/UndirectedEdgeTests.cs
@@ -21,6 +21,14 @@ public void Construction()
             var v2 = new ComparableTestVertex("v2");
             CheckEdge(new UndirectedEdge<ComparableTestVertex>(v1, v2), v1, v2);
             CheckEdge(new UndirectedEdge<ComparableTestVertex>(v1, v1), v1, v1);
+
+            // Order correctly on creation
+            CheckEdge(new UndirectedEdge<int>(2, 1), 1, 2);
+
+            // Comparable
+            var comparableV1 = new ComparableTestVertex("v1");
+            var comparableV2 = new ComparableTestVertex("v2");
+            CheckEdge(new UndirectedEdge<ComparableTestVertex>(comparableV2, comparableV1), comparableV1, comparableV2);
         }
 
         [Test]
@@ -33,16 +41,11 @@ public void Construction_Throws()
             Assert.Throws<ArgumentNullException>(() => new UndirectedEdge<TestVertex>(null, null));
             // ReSharper restore AssignNullToNotNullAttribute
 
-            Assert.Throws<ArgumentException>(() => new UndirectedEdge<int>(2, 1));
 
             // Not comparable
             var v1 = new TestVertex("v1");
             var v2 = new TestVertex("v2");
             Assert.Throws<ArgumentException>(() => new UndirectedEdge<TestVertex>(v1, v2));
-
-            var comparableV1 = new ComparableTestVertex("v1");
-            var comparableV2 = new ComparableTestVertex("v2");
-            Assert.Throws<ArgumentException>(() => new UndirectedEdge<ComparableTestVertex>(comparableV2, comparableV1));
             // ReSharper restore ObjectCreationAsStatement
         }