diff --git a/packages/repository/src/__tests__/unit/model/model.unit.ts b/packages/repository/src/__tests__/unit/model/model.unit.ts
index f924d51ed920..abe2df4c32cb 100644
--- a/packages/repository/src/__tests__/unit/model/model.unit.ts
+++ b/packages/repository/src/__tests__/unit/model/model.unit.ts
@@ -46,6 +46,8 @@ describe('model', () => {
   const flexibleDef = new ModelDefinition('Flexible');
   flexibleDef
     .addProperty('id', {type: 'string', id: true})
+    .addProperty('createdAt', Date)
+    .addSetting('hiddenProperties', ['createdAt'])
     .addSetting('strict', false);
 
   const addressDef = new ModelDefinition('Address');
@@ -121,8 +123,8 @@ describe('model', () => {
 
   class Flexible extends Entity {
     static definition = flexibleDef;
-
     id: string;
+    createdAt?: Date;
 
     constructor(data?: Partial<Flexible>) {
       super(data);
@@ -460,6 +462,16 @@ describe('model', () => {
     });
   });
 
+  it('excludes hidden properties from toJSON() output with strict false', () => {
+    const flexible = new Flexible({
+      id: '123a',
+      createdAt: new Date(),
+    });
+    expect(flexible.toJSON()).to.eql({
+      id: '123a',
+    });
+  });
+
   describe('rejectNavigationalPropertiesInData', () => {
     class Order extends Entity {
       static definition = new ModelDefinition('Order')
diff --git a/packages/repository/src/model.ts b/packages/repository/src/model.ts
index d0be36a56b23..d6e33e891141 100644
--- a/packages/repository/src/model.ts
+++ b/packages/repository/src/model.ts
@@ -265,17 +265,20 @@ export abstract class Model {
    * See function `asObject` for each property's conversion rules.
    */
   toObject(options?: Options): Object {
+    const def = (this.constructor as typeof Model).definition;
     const obj: AnyObject = {};
 
     if (options && options.ignoreUnknownProperties === false) {
+      const hiddenProperties: string[] = def?.settings.hiddenProperties || [];
       for (const p in this) {
-        const val = (this as AnyObject)[p];
-        obj[p] = asObject(val, options);
+        if (!hiddenProperties.includes(p)) {
+          const val = (this as AnyObject)[p];
+          obj[p] = asObject(val, options);
+        }
       }
       return obj;
     }
 
-    const def = (this.constructor as typeof Model).definition;
     const props = def.properties;
     const keys = Object.keys(props);