diff --git a/osu.Game/Database/RealmAccess.cs b/osu.Game/Database/RealmAccess.cs
index 7142f2b300..49bde7c505 100644
--- a/osu.Game/Database/RealmAccess.cs
+++ b/osu.Game/Database/RealmAccess.cs
@@ -98,8 +98,9 @@ namespace osu.Game.Database
         /// 46   2024-12-26    Change beat snap divisor bindings to match stable directionality ¯\_(ツ)_/¯.
         /// 47   2025-01-21    Remove right mouse button binding for absolute scroll. Never use mouse buttons (or scroll) for global actions.
         /// 48   2025-03-19    Clear online status for all qualified beatmaps (some were stuck in a qualified state due to local caching issues).
+        /// 49   2025-06-10    Reset the LegacyOnlineID to -1 for all scores that have it set to 0 (which is semantically the same) for consistency of handling with OnlineID.
         /// </summary>
-        private const int schema_version = 48;
+        private const int schema_version = 49;
 
         /// <summary>
         /// Lock object which is held during <see cref="BlockAllOperations"/> sections, blocking realm retrieval during blocking periods.
@@ -1255,6 +1256,12 @@ namespace osu.Game.Database
                     foreach (var beatmap in beatmaps)
                         beatmap.ResetOnlineInfo(resetOnlineId: false);
                     break;
+
+                case 49:
+                    foreach (var score in migration.NewRealm.All<ScoreInfo>().Where(s => s.LegacyOnlineID == 0))
+                        score.LegacyOnlineID = -1;
+
+                    break;
             }
 
             Logger.Log($"Migration completed in {stopwatch.ElapsedMilliseconds}ms");
diff --git a/osu.Game/Scoring/Legacy/LegacyScoreDecoder.cs b/osu.Game/Scoring/Legacy/LegacyScoreDecoder.cs
index a32c05c4eb..cf6819b086 100644
--- a/osu.Game/Scoring/Legacy/LegacyScoreDecoder.cs
+++ b/osu.Game/Scoring/Legacy/LegacyScoreDecoder.cs
@@ -110,6 +110,9 @@ namespace osu.Game.Scoring.Legacy
                 else if (version >= 20121008)
                     scoreInfo.LegacyOnlineID = sr.ReadInt32();
 
+                if (scoreInfo.LegacyOnlineID == 0)
+                    scoreInfo.LegacyOnlineID = -1;
+
                 byte[] compressedScoreInfo = null;
 
                 if (version >= 30000001)