diff --git a/com.unity.netcode.gameobjects/CHANGELOG.md b/com.unity.netcode.gameobjects/CHANGELOG.md
index 4502f16caa..609399c947 100644
--- a/com.unity.netcode.gameobjects/CHANGELOG.md
+++ b/com.unity.netcode.gameobjects/CHANGELOG.md
@@ -12,6 +12,7 @@ Additional documentation and release notes are available at [Multiplayer Documen
 
 ### Fixed
 
+- Fixed issue where collections v2.2.x was not supported when using UTP v2.2.x within Unity v2022.3. (#3033)
 - Fixed issue where the `NetworkManagerHelper` was continuing to check for hierarchy changes when in play mode. (#3027)
 
 ### Changed
diff --git a/com.unity.netcode.gameobjects/Runtime/NetworkVariable/CollectionSerializationUtility.cs b/com.unity.netcode.gameobjects/Runtime/NetworkVariable/CollectionSerializationUtility.cs
index 096b2a4c62..ae8cda6871 100644
--- a/com.unity.netcode.gameobjects/Runtime/NetworkVariable/CollectionSerializationUtility.cs
+++ b/com.unity.netcode.gameobjects/Runtime/NetworkVariable/CollectionSerializationUtility.cs
@@ -505,8 +505,13 @@ public static void WriteNativeListDelta<T>(FastBufferWriter writer, ref NativeLi
             writer.WriteValueSafe(changes);
             unsafe
             {
+#if UTP_TRANSPORT_2_0_ABOVE
+                var ptr = value.GetUnsafePtr();
+                var prevPtr = previousValue.GetUnsafePtr();
+#else
                 var ptr = (T*)value.GetUnsafePtr();
                 var prevPtr = (T*)previousValue.GetUnsafePtr();
+#endif
                 for (int i = 0; i < value.Length; ++i)
                 {
                     if (changes.IsSet(i))
@@ -549,7 +554,11 @@ public static void ReadNativeListDelta<T>(FastBufferReader reader, ref NativeLis
 
                 unsafe
                 {
+#if UTP_TRANSPORT_2_0_ABOVE
+                    var ptr = value.GetUnsafePtr();
+#else
                     var ptr = (T*)value.GetUnsafePtr();
+#endif
                     for (var i = 0; i < value.Length; ++i)
                     {
                         if (changes.IsSet(i))
@@ -571,8 +580,13 @@ public static void ReadNativeListDelta<T>(FastBufferReader reader, ref NativeLis
         public static unsafe void WriteNativeHashSetDelta<T>(FastBufferWriter writer, ref NativeHashSet<T> value, ref NativeHashSet<T> previousValue) where T : unmanaged, IEquatable<T>
         {
             // See WriteHashSet; this is the same algorithm, adjusted for the NativeHashSet API
+#if UTP_TRANSPORT_2_0_ABOVE
+            var added = stackalloc T[value.Count];
+            var removed = stackalloc T[previousValue.Count];
+#else
             var added = stackalloc T[value.Count()];
             var removed = stackalloc T[previousValue.Count()];
+#endif
             var addedCount = 0;
             var removedCount = 0;
             foreach (var item in value)
@@ -592,8 +606,11 @@ public static unsafe void WriteNativeHashSetDelta<T>(FastBufferWriter writer, re
                     ++removedCount;
                 }
             }
-
+#if UTP_TRANSPORT_2_0_ABOVE
+            if (addedCount + removedCount >= value.Count)
+#else
             if (addedCount + removedCount >= value.Count())
+#endif
             {
                 writer.WriteByteSafe(1);
                 writer.WriteValueSafe(value);
@@ -643,9 +660,15 @@ public static unsafe void WriteNativeHashMapDelta<TKey, TVal>(FastBufferWriter w
             where TVal : unmanaged
         {
             // See WriteDictionary; this is the same algorithm, adjusted for the NativeHashMap API
+#if UTP_TRANSPORT_2_0_ABOVE
+            var added = stackalloc KVPair<TKey, TVal>[value.Count];
+            var changed = stackalloc KVPair<TKey, TVal>[value.Count];
+            var removed = stackalloc KVPair<TKey, TVal>[previousValue.Count];
+#else
             var added = stackalloc KeyValue<TKey, TVal>[value.Count()];
             var changed = stackalloc KeyValue<TKey, TVal>[value.Count()];
             var removed = stackalloc KeyValue<TKey, TVal>[previousValue.Count()];
+#endif
             var addedCount = 0;
             var changedCount = 0;
             var removedCount = 0;
@@ -672,8 +695,11 @@ public static unsafe void WriteNativeHashMapDelta<TKey, TVal>(FastBufferWriter w
                     ++removedCount;
                 }
             }
-
+#if UTP_TRANSPORT_2_0_ABOVE
+            if (addedCount + removedCount + changedCount >= value.Count)
+#else
             if (addedCount + removedCount + changedCount >= value.Count())
+#endif
             {
                 writer.WriteByteSafe(1);
                 writer.WriteValueSafe(value);
diff --git a/com.unity.netcode.gameobjects/Runtime/NetworkVariable/NetworkVariableSerialization.cs b/com.unity.netcode.gameobjects/Runtime/NetworkVariable/NetworkVariableSerialization.cs
index 70c94cf3bb..2d77e568ad 100644
--- a/com.unity.netcode.gameobjects/Runtime/NetworkVariable/NetworkVariableSerialization.cs
+++ b/com.unity.netcode.gameobjects/Runtime/NetworkVariable/NetworkVariableSerialization.cs
@@ -1728,8 +1728,13 @@ internal static unsafe bool ValueEqualsList<TValueType>(ref NativeList<TValueTyp
                 return false;
             }
 
+#if UTP_TRANSPORT_2_0_ABOVE
+            var aptr = a.GetUnsafePtr();
+            var bptr = b.GetUnsafePtr();
+#else
             var aptr = (TValueType*)a.GetUnsafePtr();
             var bptr = (TValueType*)b.GetUnsafePtr();
+#endif
             return UnsafeUtility.MemCmp(aptr, bptr, sizeof(TValueType) * a.Length) == 0;
         }
 #endif
@@ -1857,9 +1862,14 @@ internal static unsafe bool EqualityEqualsNativeList<TValueType>(ref NativeList<
             {
                 return false;
             }
-
+#if UTP_TRANSPORT_2_0_ABOVE
+            var aptr = a.GetUnsafePtr();
+            var bptr = b.GetUnsafePtr();
+#else
             var aptr = (TValueType*)a.GetUnsafePtr();
             var bptr = (TValueType*)b.GetUnsafePtr();
+#endif
+
             for (var i = 0; i < a.Length; ++i)
             {
                 if (!EqualityEquals(ref aptr[i], ref bptr[i]))
@@ -1883,7 +1893,11 @@ internal static bool EqualityEqualsNativeHashSet<TValueType>(ref NativeHashSet<T
                 return true;
             }
 
+#if UTP_TRANSPORT_2_0_ABOVE
+            if (a.Count != b.Count)
+#else
             if (a.Count() != b.Count())
+#endif
             {
                 return false;
             }
@@ -1995,8 +2009,11 @@ internal static bool GenericEqualsNativeHashMap(ref NativeHashMap<TKey, TVal> a,
             {
                 return true;
             }
-
+#if UTP_TRANSPORT_2_0_ABOVE
+            if (a.Count != b.Count)
+#else
             if (a.Count() != b.Count())
+#endif
             {
                 return false;
             }
diff --git a/com.unity.netcode.gameobjects/Runtime/NetworkVariable/ResizableBitVector.cs b/com.unity.netcode.gameobjects/Runtime/NetworkVariable/ResizableBitVector.cs
index 5b3ec1e7ca..b4b4b76e83 100644
--- a/com.unity.netcode.gameobjects/Runtime/NetworkVariable/ResizableBitVector.cs
+++ b/com.unity.netcode.gameobjects/Runtime/NetworkVariable/ResizableBitVector.cs
@@ -95,11 +95,19 @@ public unsafe void NetworkSerialize<T>(BufferSerializer<T> serializer) where T :
             {
                 if (serializer.IsReader)
                 {
+#if UTP_TRANSPORT_2_0_ABOVE
+                    serializer.GetFastBufferReader().ReadBytesSafe(ptr, length);
+#else
                     serializer.GetFastBufferReader().ReadBytesSafe((byte*)ptr, length);
+#endif
                 }
                 else
                 {
+#if UTP_TRANSPORT_2_0_ABOVE
+                    serializer.GetFastBufferWriter().WriteBytesSafe(ptr, length);
+#else
                     serializer.GetFastBufferWriter().WriteBytesSafe((byte*)ptr, length);
+#endif
                 }
             }
         }
diff --git a/com.unity.netcode.gameobjects/Runtime/Serialization/FastBufferWriter.cs b/com.unity.netcode.gameobjects/Runtime/Serialization/FastBufferWriter.cs
index aa50ad6a9a..05c14eb1a2 100644
--- a/com.unity.netcode.gameobjects/Runtime/Serialization/FastBufferWriter.cs
+++ b/com.unity.netcode.gameobjects/Runtime/Serialization/FastBufferWriter.cs
@@ -772,7 +772,11 @@ public unsafe void WriteBytes(NativeArray<byte> value, int size = -1, int offset
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public unsafe void WriteBytes(NativeList<byte> value, int size = -1, int offset = 0)
         {
+#if UTP_TRANSPORT_2_0_ABOVE
+            byte* ptr = value.GetUnsafePtr();
+#else
             byte* ptr = (byte*)value.GetUnsafePtr();
+#endif
             WriteBytes(ptr, size == -1 ? value.Length : size, offset);
         }
 
@@ -816,7 +820,11 @@ public unsafe void WriteBytesSafe(NativeArray<byte> value, int size = -1, int of
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public unsafe void WriteBytesSafe(NativeList<byte> value, int size = -1, int offset = 0)
         {
+#if UTP_TRANSPORT_2_0_ABOVE
+            byte* ptr = value.GetUnsafePtr();
+#else
             byte* ptr = (byte*)value.GetUnsafePtr();
+#endif
             WriteBytesSafe(ptr, size == -1 ? value.Length : size, offset);
         }
 
@@ -985,7 +993,12 @@ internal unsafe void WriteUnmanagedSafe<T>(NativeArray<T> value) where T : unman
         internal unsafe void WriteUnmanaged<T>(NativeList<T> value) where T : unmanaged
         {
             WriteUnmanaged(value.Length);
+
+#if UTP_TRANSPORT_2_0_ABOVE
+            var ptr = value.GetUnsafePtr();
+#else
             var ptr = (T*)value.GetUnsafePtr();
+#endif
             {
                 byte* bytes = (byte*)ptr;
                 WriteBytes(bytes, sizeof(T) * value.Length);
@@ -995,7 +1008,11 @@ internal unsafe void WriteUnmanaged<T>(NativeList<T> value) where T : unmanaged
         internal unsafe void WriteUnmanagedSafe<T>(NativeList<T> value) where T : unmanaged
         {
             WriteUnmanagedSafe(value.Length);
+#if UTP_TRANSPORT_2_0_ABOVE
+            var ptr = value.GetUnsafePtr();
+#else
             var ptr = (T*)value.GetUnsafePtr();
+#endif
             {
                 byte* bytes = (byte*)ptr;
                 WriteBytesSafe(bytes, sizeof(T) * value.Length);
@@ -1193,7 +1210,11 @@ public void WriteValue<T>(NativeList<T> value, ForGeneric unused = default) wher
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         internal void WriteValueSafe<T>(NativeHashSet<T> value) where T : unmanaged, IEquatable<T>
         {
+#if UTP_TRANSPORT_2_0_ABOVE
+            WriteUnmanagedSafe(value.Count);
+#else
             WriteUnmanagedSafe(value.Count());
+#endif
             foreach (var item in value)
             {
                 var iReffable = item;
@@ -1206,7 +1227,11 @@ internal void WriteValueSafe<TKey, TVal>(NativeHashMap<TKey, TVal> value)
             where TKey : unmanaged, IEquatable<TKey>
             where TVal : unmanaged
         {
+#if UTP_TRANSPORT_2_0_ABOVE
+            WriteUnmanagedSafe(value.Count);
+#else
             WriteUnmanagedSafe(value.Count());
+#endif
             foreach (var item in value)
             {
                 (var key, var val) = (item.Key, item.Value);