diff --git a/src/EFCore.Relational/Metadata/Internal/RelationalModel.cs b/src/EFCore.Relational/Metadata/Internal/RelationalModel.cs
index c2cc06d124c..839b990028e 100644
--- a/src/EFCore.Relational/Metadata/Internal/RelationalModel.cs
+++ b/src/EFCore.Relational/Metadata/Internal/RelationalModel.cs
@@ -547,6 +547,23 @@ private static void CreateTableMapping(
 
         foreach (var complexProperty in mappedType.GetComplexProperties())
         {
+            // For TPT: skip complex properties declared on base entity types that have their own table.
+            // Those complex properties will be processed when mapping the declaring entity type's own table.
+            // For TPC, all properties (including inherited) must be included in each concrete table, so skip this check.
+            if (mappedType is IEntityType mappedEntityType
+                && mappedEntityType.GetMappingStrategy() != RelationalAnnotationNames.TpcMappingStrategy
+                && complexProperty.DeclaringType is IEntityType complexPropertyDeclaringEntityType
+                && complexPropertyDeclaringEntityType != mappedEntityType)
+            {
+                var declaringTableName = complexPropertyDeclaringEntityType.GetTableName();
+                if (declaringTableName != null
+                    && (declaringTableName != mappedTable.Name
+                        || complexPropertyDeclaringEntityType.GetSchema() != mappedTable.Schema))
+                {
+                    continue;
+                }
+            }
+
             var complexType = complexProperty.ComplexType;
 
             var complexTableMappings =
diff --git a/test/EFCore.Relational.Tests/Metadata/RelationalModelTest.cs b/test/EFCore.Relational.Tests/Metadata/RelationalModelTest.cs
index 13c2322687d..e4ec9d5d600 100644
--- a/test/EFCore.Relational.Tests/Metadata/RelationalModelTest.cs
+++ b/test/EFCore.Relational.Tests/Metadata/RelationalModelTest.cs
@@ -3322,6 +3322,27 @@ public void Complex_property_json_column_is_nullable_in_TPH_hierarchy()
             Assert.IsType<JsonColumn>(jsonColumn);
         }
 
+        [ConditionalFact]
+        public void Complex_property_json_column_is_not_duplicated_in_TPT_child_tables()
+        {
+            var modelBuilder = CreateConventionModelBuilder();
+
+            modelBuilder.Entity<TptBaseEntityWithComplexProperty>()
+                .UseTptMappingStrategy()
+                .ComplexProperty(e => e.ComplexProperty, b => b.ToJson());
+            modelBuilder.Entity<TptDerivedEntityWithoutComplexProperty>();
+
+            var model = modelBuilder.FinalizeModel();
+            var relationalModel = model.GetRelationalModel();
+
+            var baseTable = relationalModel.Tables.Single(t => t.Name == nameof(TptBaseEntityWithComplexProperty));
+            var childTable = relationalModel.Tables.Single(t => t.Name == nameof(TptDerivedEntityWithoutComplexProperty));
+
+            // The JSON column for the base complex property must appear only in the base table
+            Assert.Contains(baseTable.Columns, c => c.Name == nameof(TptBaseEntityWithComplexProperty.ComplexProperty));
+            Assert.DoesNotContain(childTable.Columns, c => c.Name == nameof(TptBaseEntityWithComplexProperty.ComplexProperty));
+        }
+
         [ConditionalFact]
         public void Can_use_relational_model_with_functions_and_json_owned_types()
         {
@@ -3497,6 +3518,14 @@ private class TphEntityWithComplexProperty : TphBaseEntity
             public ComplexData ComplexProperty { get; set; }
         }
 
+        private abstract class TptBaseEntityWithComplexProperty
+        {
+            public int Id { get; set; }
+            public ComplexData ComplexProperty { get; set; }
+        }
+
+        private class TptDerivedEntityWithoutComplexProperty : TptBaseEntityWithComplexProperty;
+
         [ComplexType]
         private class ComplexData
         {