diff --git a/Assets/Mirror/Runtime/NetworkIdentity.cs b/Assets/Mirror/Runtime/NetworkIdentity.cs
index 74c2a5405..763a8ad34 100644
--- a/Assets/Mirror/Runtime/NetworkIdentity.cs
+++ b/Assets/Mirror/Runtime/NetworkIdentity.cs
@@ -24,7 +24,8 @@ public enum Visibility { Default, ForceHidden, ForceShown }
 
     public struct NetworkIdentitySerialization
     {
-        public float tickTimeStamp;
+        // IMPORTANT: int tick avoids floating point inaccuracy over days/weeks
+        public int tick;
         public NetworkWriter ownerWriter;
         public NetworkWriter observersWriter;
         // TODO there is probably a more simple way later
@@ -940,11 +941,12 @@ internal void OnSerializeAllSafely(bool initialState, NetworkWriter ownerWriter,
         }
 
         // get cached serialization for this tick (or serialize if none yet)
-        // IMPORTANT: needs FRAME TIME which doesn't change during THIS FRAME!
-        internal NetworkIdentitySerialization GetSerializationAtTick(float tickTimeStamp)
+        // IMPORTANT: int tick avoids floating point inaccuracy over days/weeks
+        internal NetworkIdentitySerialization GetSerializationAtTick(int tick)
         {
-            // serialize fresh if tick is newer than last one
-            if (lastSerialization.tickTimeStamp < tickTimeStamp)
+            // reserialize if tick is different than last changed.
+            // NOTE: != instead of < because int.max+1 overflows at some point.
+            if (lastSerialization.tick != tick)
             {
                 // reset
                 lastSerialization.ownerWriter.Position = 0;
@@ -957,8 +959,8 @@ internal NetworkIdentitySerialization GetSerializationAtTick(float tickTimeStamp
                                      lastSerialization.observersWriter,
                                      out lastSerialization.observersWritten);
 
-                // set timestamp
-                lastSerialization.tickTimeStamp = tickTimeStamp;
+                // set tick
+                lastSerialization.tick = tick;
                 //Debug.Log($"{name} (netId={netId}) serialized for tick={tickTimeStamp}");
             }
 
diff --git a/Assets/Mirror/Runtime/NetworkServer.cs b/Assets/Mirror/Runtime/NetworkServer.cs
index 165cf3ebf..235b09ff7 100644
--- a/Assets/Mirror/Runtime/NetworkServer.cs
+++ b/Assets/Mirror/Runtime/NetworkServer.cs
@@ -1432,8 +1432,8 @@ public static void RebuildObservers(NetworkIdentity identity, bool initialize)
         static NetworkWriter GetEntitySerializationForConnection(NetworkIdentity identity, NetworkConnectionToClient connection)
         {
             // get serialization for this entity (cached)
-            // IMPORTANT: needs FRAME TIME which doesn't change during THIS FRAME!
-            NetworkIdentitySerialization serialization = identity.GetSerializationAtTick(Time.time);
+            // IMPORTANT: int tick avoids floating point inaccuracy over days/weeks
+            NetworkIdentitySerialization serialization = identity.GetSerializationAtTick(Time.frameCount);
 
             // is this entity owned by this connection?
             bool owned = identity.connectionToClient == connection;
diff --git a/Assets/Mirror/Tests/Runtime/NetworkIdentityTests.cs b/Assets/Mirror/Tests/Runtime/NetworkIdentityTests.cs
index 8b2e6f6fe..e92433b73 100644
--- a/Assets/Mirror/Tests/Runtime/NetworkIdentityTests.cs
+++ b/Assets/Mirror/Tests/Runtime/NetworkIdentityTests.cs
@@ -64,14 +64,15 @@ public IEnumerator OnDestroyIsServerTrueWhenNetworkServerDestroyIsCalled()
         public IEnumerator TestSerializationWithLargeTimestamps()
         {
             // 14 * 24 hours per day * 60 minutes per hour * 60 seconds per minute = 14 days
-            float time = 14 * 24 * 60 * 60;
-            NetworkIdentitySerialization serialization = identity.GetSerializationAtTick(time);
-            // advance time by 50ms (20 fps)
-            time += 0.05f;
-            NetworkIdentitySerialization serializationNew = identity.GetSerializationAtTick(time);
+            // NOTE: change this to 'float' to see the tests fail
+            int tick = 14 * 24 * 60 * 60;
+            NetworkIdentitySerialization serialization = identity.GetSerializationAtTick(tick);
+            // advance tick
+            ++tick;
+            NetworkIdentitySerialization serializationNew = identity.GetSerializationAtTick(tick);
 
             // if the serialization has been changed the tickTimeStamp should have moved
-            Assert.That(serialization.tickTimeStamp == serializationNew.tickTimeStamp, Is.False);
+            Assert.That(serialization.tick == serializationNew.tick, Is.False);
             yield break;
         }
     }