diff --git a/SabreTools.Serialization/Wrappers/N3DS.cs b/SabreTools.Serialization/Wrappers/N3DS.cs
index 02f79a2f..9cb9f13f 100644
--- a/SabreTools.Serialization/Wrappers/N3DS.cs
+++ b/SabreTools.Serialization/Wrappers/N3DS.cs
@@ -304,6 +304,7 @@ namespace SabreTools.Serialization.Wrappers
                 return [];
 
             byte[] partitionIdBytes = BitConverter.GetBytes(header.PartitionId);
+            Array.Reverse(partitionIdBytes);
             return [.. partitionIdBytes, .. PlainCounter];
         }
 
@@ -322,6 +323,7 @@ namespace SabreTools.Serialization.Wrappers
                 return [];
 
             byte[] partitionIdBytes = BitConverter.GetBytes(header.PartitionId);
+            Array.Reverse(partitionIdBytes);
             return [.. partitionIdBytes, .. ExefsCounter];
         }
 
@@ -340,6 +342,7 @@ namespace SabreTools.Serialization.Wrappers
                 return [];
 
             byte[] partitionIdBytes = BitConverter.GetBytes(header.PartitionId);
+            Array.Reverse(partitionIdBytes);
             return [.. partitionIdBytes, .. RomfsCounter];
         }