diff --git a/docs/release-notes.md b/docs/release-notes.md
index 6d505d40..732cd530 100644
--- a/docs/release-notes.md
+++ b/docs/release-notes.md
@@ -9,6 +9,7 @@
     * Added `--use-current-shell` to avoid opening a separate terminal window.
     * Fixed `--no-terminal` still opening a terminal window, even if nothing is logged to it (thanks to Ryhon0!).
   * SMAPI now fixes many case-sensitive mod file path issues automatically.
+  * Dropped update checks for the unofficial 64-bit patcher (obsolete since SMAPI 3.12.6).
   * Improved translations. Thanks to ChulkyBow (updated Ukrainian)!
 
 * For the Console Commands mod:
diff --git a/src/SMAPI/Constants.cs b/src/SMAPI/Constants.cs
index 6b9e9b05..2fac8c94 100644
--- a/src/SMAPI/Constants.cs
+++ b/src/SMAPI/Constants.cs
@@ -291,21 +291,6 @@ namespace StardewModdingAPI
             return new PlatformAssemblyMap(targetPlatform, removeAssemblyReferences.ToArray(), targetAssemblies.ToArray());
         }
 
-        /// <summary>Get whether the game assembly was patched by Stardew64Installer.</summary>
-        /// <param name="version">The version of Stardew64Installer which was applied to the game assembly, if any.</param>
-        internal static bool IsPatchedByStardew64Installer(out ISemanticVersion version)
-        {
-            PropertyInfo property = typeof(Game1).GetProperty("Stardew64InstallerVersion");
-            if (property == null)
-            {
-                version = null;
-                return false;
-            }
-
-            version = new SemanticVersion((string)property.GetValue(null));
-            return true;
-        }
-
 
         /*********
         ** Private methods
diff --git a/src/SMAPI/Framework/Models/SConfig.cs b/src/SMAPI/Framework/Models/SConfig.cs
index 35180df2..1e78f316 100644
--- a/src/SMAPI/Framework/Models/SConfig.cs
+++ b/src/SMAPI/Framework/Models/SConfig.cs
@@ -52,9 +52,6 @@ namespace StardewModdingAPI.Framework.Models
         /// <summary>SMAPI's GitHub project name, used to perform update checks.</summary>
         public string GitHubProjectName { get; set; }
 
-        /// <summary>Stardew64Installer's GitHub project name, used to perform update checks.</summary>
-        public string Stardew64InstallerGitHubProjectName { get; set; }
-
         /// <summary>The base URL for SMAPI's web API, used to perform update checks.</summary>
         public string WebApiBaseUrl { get; set; }
 
diff --git a/src/SMAPI/Framework/SCore.cs b/src/SMAPI/Framework/SCore.cs
index cc531de9..b471c383 100644
--- a/src/SMAPI/Framework/SCore.cs
+++ b/src/SMAPI/Framework/SCore.cs
@@ -1450,39 +1450,6 @@ namespace StardewModdingAPI.Framework
                         this.LogManager.WriteUpdateMarker(updateFound.ToString(), updateUrl);
                 }
 
-                // check Stardew64Installer version
-                if (Constants.IsPatchedByStardew64Installer(out ISemanticVersion patchedByVersion))
-                {
-                    try
-                    {
-                        // fetch update check
-                        ModEntryModel response = client.GetModInfo(new[] { new ModSearchEntryModel("Steviegt6.Stardew64Installer", patchedByVersion, new[] { $"GitHub:{this.Settings.Stardew64InstallerGitHubProjectName}" }) }, apiVersion: Constants.ApiVersion, gameVersion: Constants.GameVersion, platform: Constants.Platform).Single().Value;
-                        ISemanticVersion updateFound = response.SuggestedUpdate?.Version;
-                        string updateUrl = response.SuggestedUpdate?.Url ?? Constants.HomePageUrl;
-
-                        // log message
-                        if (updateFound != null)
-                            this.Monitor.Log($"You can update Stardew64Installer to {updateFound}: {updateUrl}", LogLevel.Alert);
-                        else
-                            this.Monitor.Log("   Stardew64Installer okay.");
-
-                        // show errors
-                        if (response.Errors.Any())
-                        {
-                            this.Monitor.Log("Couldn't check for a new version of Stardew64Installer. This won't affect your game, but you may not be notified of new versions if this keeps happening.", LogLevel.Warn);
-                            this.Monitor.Log($"Error: {string.Join("\n", response.Errors)}");
-                        }
-                    }
-                    catch (Exception ex)
-                    {
-                        this.Monitor.Log("Couldn't check for a new version of Stardew64Installer. This won't affect your game, but you won't be notified of new versions if this keeps happening.", LogLevel.Warn);
-                        this.Monitor.Log(ex is WebException && ex.InnerException == null
-                            ? $"Error: {ex.Message}"
-                            : $"Error: {ex.GetLogSummary()}"
-                        );
-                    }
-                }
-
                 // check mod versions
                 if (mods.Any())
                 {
diff --git a/src/SMAPI/SMAPI.config.json b/src/SMAPI/SMAPI.config.json
index e62c8880..49056e83 100644
--- a/src/SMAPI/SMAPI.config.json
+++ b/src/SMAPI/SMAPI.config.json
@@ -69,11 +69,6 @@ copy all the settings, or you may cause bugs due to overridden changes in future
      */
     "GitHubProjectName": "Pathoschild/SMAPI",
 
-    /**
-     * Stardew64Installer's GitHub project name, used to perform update checks.
-     */
-    "Stardew64InstallerGitHubProjectName": "Steviegt6/Stardew64Installer",
-
     /**
      * The base URL for SMAPI's web API, used to perform update checks.
      */