diff --git a/Src/Newtonsoft.Json.Tests/Serialization/ImmutableCollectionsTests.cs b/Src/Newtonsoft.Json.Tests/Serialization/ImmutableCollectionsTests.cs
index 81876c5d..09d8c461 100644
--- a/Src/Newtonsoft.Json.Tests/Serialization/ImmutableCollectionsTests.cs
+++ b/Src/Newtonsoft.Json.Tests/Serialization/ImmutableCollectionsTests.cs
@@ -304,6 +304,8 @@ namespace Newtonsoft.Json.Tests.Serialization
             Assert.IsTrue(l.Contains("3"));
             Assert.IsTrue(l.Contains("II"));
             Assert.IsTrue(l.Contains("One"));
+
+            Assert.IsTrue(l is ImmutableHashSet<string>);
         }
         #endregion
 
@@ -395,6 +397,8 @@ namespace Newtonsoft.Json.Tests.Serialization
             Assert.AreEqual("One", l[1]);
             Assert.AreEqual("II", l[2]);
             Assert.AreEqual("3", l[3]);
+
+            Assert.IsTrue(l is ImmutableDictionary<int, string>);
         }
         #endregion
 
diff --git a/Src/Newtonsoft.Json/Utilities/ImmutableCollectionsUtils.cs b/Src/Newtonsoft.Json/Utilities/ImmutableCollectionsUtils.cs
index ab3b5522..dfe5d45e 100644
--- a/Src/Newtonsoft.Json/Utilities/ImmutableCollectionsUtils.cs
+++ b/Src/Newtonsoft.Json/Utilities/ImmutableCollectionsUtils.cs
@@ -90,7 +90,7 @@ namespace Newtonsoft.Json.Utilities
             new ImmutableCollectionTypeInfo(ImmutableQueueGenericTypeName, ImmutableQueueGenericTypeName, ImmutableQueueTypeName),
             new ImmutableCollectionTypeInfo(ImmutableStackGenericInterfaceTypeName, ImmutableStackGenericTypeName, ImmutableStackTypeName),
             new ImmutableCollectionTypeInfo(ImmutableStackGenericTypeName, ImmutableStackGenericTypeName, ImmutableStackTypeName),
-            new ImmutableCollectionTypeInfo(ImmutableSetGenericInterfaceTypeName, ImmutableSortedSetGenericTypeName, ImmutableSortedSetTypeName),
+            new ImmutableCollectionTypeInfo(ImmutableSetGenericInterfaceTypeName, ImmutableHashSetGenericTypeName, ImmutableHashSetTypeName),
             new ImmutableCollectionTypeInfo(ImmutableSortedSetGenericTypeName, ImmutableSortedSetGenericTypeName, ImmutableSortedSetTypeName),
             new ImmutableCollectionTypeInfo(ImmutableHashSetGenericTypeName, ImmutableHashSetGenericTypeName, ImmutableHashSetTypeName),
             new ImmutableCollectionTypeInfo(ImmutableArrayGenericTypeName, ImmutableArrayGenericTypeName, ImmutableArrayTypeName)
@@ -106,7 +106,7 @@ namespace Newtonsoft.Json.Utilities
 
         private static readonly IList<ImmutableCollectionTypeInfo> DictionaryContractImmutableCollectionDefinitions = new List<ImmutableCollectionTypeInfo>
         {
-            new ImmutableCollectionTypeInfo(ImmutableDictionaryGenericInterfaceTypeName, ImmutableSortedDictionaryGenericTypeName, ImmutableSortedDictionaryTypeName),
+            new ImmutableCollectionTypeInfo(ImmutableDictionaryGenericInterfaceTypeName, ImmutableDictionaryGenericTypeName, ImmutableDictionaryTypeName),
             new ImmutableCollectionTypeInfo(ImmutableSortedDictionaryGenericTypeName, ImmutableSortedDictionaryGenericTypeName, ImmutableSortedDictionaryTypeName),
             new ImmutableCollectionTypeInfo(ImmutableDictionaryGenericTypeName, ImmutableDictionaryGenericTypeName, ImmutableDictionaryTypeName)
         };