diff --git a/src/Umbraco.Infrastructure/Migrations/Upgrade/UmbracoPlan.cs b/src/Umbraco.Infrastructure/Migrations/Upgrade/UmbracoPlan.cs
index 953228c3ff67..d65c05660c3c 100644
--- a/src/Umbraco.Infrastructure/Migrations/Upgrade/UmbracoPlan.cs
+++ b/src/Umbraco.Infrastructure/Migrations/Upgrade/UmbracoPlan.cs
@@ -186,6 +186,9 @@ protected virtual void DefinePlan()
         To<V_17_4_0.AddExternalMemberTables>("{D7E8F9A0-B1C2-4D3E-A5F6-7890ABCDEF12}");
         To<V_17_4_0.FixLabelDataTypeDbTypeFromConfiguration>("{3F9B6A1C-7D84-4E2B-9C15-6A2E8F3D5B47}");
 
+        // To 17.6.0
+        To<V_17_6_0.AddContentTypeIdIndexForContent>("{3A1A8047-74AE-491A-B2C4-0BAE4A1289EC}");
+
         // To 18.0.0
         // TODO (V18): Enable on 18 branch
         //// To<V_18_0_0.MigrateSingleBlockList>("{74332C49-B279-4945-8943-F8F00B1F5949}");
diff --git a/src/Umbraco.Infrastructure/Migrations/Upgrade/V_17_6_0/AddContentTypeIdIndexForContent.cs b/src/Umbraco.Infrastructure/Migrations/Upgrade/V_17_6_0/AddContentTypeIdIndexForContent.cs
new file mode 100644
index 000000000000..8bbc4b503e9f
--- /dev/null
+++ b/src/Umbraco.Infrastructure/Migrations/Upgrade/V_17_6_0/AddContentTypeIdIndexForContent.cs
@@ -0,0 +1,41 @@
+// Copyright (c) Umbraco.
+// See LICENSE for more details.
+
+using Umbraco.Cms.Infrastructure.Persistence.Dtos;
+
+namespace Umbraco.Cms.Infrastructure.Migrations.Upgrade.V_17_6_0;
+
+/// <summary>
+/// Adds an index on the contentTypeId column of the umbracoContent table to support efficient
+/// content-type-scoped queries (e.g. the content cache rebuild triggered by content type changes).
+/// </summary>
+public class AddContentTypeIdIndexForContent : AsyncMigrationBase
+{
+    private const string IndexName = "IX_" + ContentDto.TableName + "_" + ContentDto.ContentTypeIdColumnName;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="AddContentTypeIdIndexForContent"/> class.
+    /// </summary>
+    /// <param name="context">The migration context.</param>
+    public AddContentTypeIdIndexForContent(IMigrationContext context)
+        : base(context)
+    {
+    }
+
+    /// <inheritdoc/>
+    protected override Task MigrateAsync()
+    {
+        if (IndexExists(IndexName))
+        {
+            return Task.CompletedTask;
+        }
+
+        // Give scope for the migration to complete within the command timeout, which may be necessary on large datasets.
+        EnsureLongCommandTimeout(Database);
+
+        // Create the index from the definition on ContentDto, so it matches a fresh install exactly.
+        CreateIndex<ContentDto>(IndexName);
+
+        return Task.CompletedTask;
+    }
+}
diff --git a/src/Umbraco.Infrastructure/Persistence/Dtos/ContentDto.cs b/src/Umbraco.Infrastructure/Persistence/Dtos/ContentDto.cs
index a7c7e9ae92df..b62dcb897285 100644
--- a/src/Umbraco.Infrastructure/Persistence/Dtos/ContentDto.cs
+++ b/src/Umbraco.Infrastructure/Persistence/Dtos/ContentDto.cs
@@ -29,6 +29,7 @@ public class ContentDto
     /// </summary>
     [Column(ContentTypeIdColumnName)]
     [ForeignKey(typeof(ContentTypeDto), Column = ContentTypeDto.NodeIdColumnName)]
+    [Index(IndexTypes.NonClustered, Name = "IX_" + TableName + "_" + ContentTypeIdColumnName)]
     public int ContentTypeId { get; set; }
 
     /// <summary>