diff --git a/rdmo/projects/static/projects/js/project_questions/services.js b/rdmo/projects/static/projects/js/project_questions/services.js
index f98236b6f9..f7079016d5 100644
--- a/rdmo/projects/static/projects/js/project_questions/services.js
+++ b/rdmo/projects/static/projects/js/project_questions/services.js
@@ -796,9 +796,11 @@ angular.module('project_questions')
             if (question === null) {
                 // this is the id of a new valueset
                 value.value_type = 'text';
+                value.widget_type = 'text';
                 value.unit = '';
             } else {
                 value.value_type = question.value_type;
+                value.widget_type = question.widget_type;
                 value.unit = question.unit;
             }
 
diff --git a/rdmo/projects/tests/test_validator_conflict.py b/rdmo/projects/tests/test_validator_conflict.py
index e48191c6ce..c6b97761b4 100644
--- a/rdmo/projects/tests/test_validator_conflict.py
+++ b/rdmo/projects/tests/test_validator_conflict.py
@@ -13,11 +13,15 @@
 
 
 def test_serializer_create(db):
+    value = Value.objects.get(project_id=project_id, snapshot=None, attribute__path=attribute_path)
+
+    class MockedRequest:
+        data = {}
+
     class MockedView:
+        request = MockedRequest()
         project = Project.objects.get(id=project_id)
 
-    value = Value.objects.get(project_id=project_id, snapshot=None, attribute__path=attribute_path)
-
     validator = ValueConflictValidator()
     serializer = ValueSerializer()
     serializer.context['view'] = MockedView()
@@ -31,11 +35,15 @@ class MockedView:
 
 
 def test_serializer_create_error(db):
+    value = Value.objects.get(project_id=project_id, snapshot=None, attribute__path=attribute_path)
+
+    class MockedRequest:
+        data = {}
+
     class MockedView:
+        request = MockedRequest()
         project = Project.objects.get(id=project_id)
 
-    value = Value.objects.get(project_id=project_id, snapshot=None, attribute__path=attribute_path)
-
     validator = ValueConflictValidator()
     serializer = ValueSerializer()
     serializer.context['view'] = MockedView()
@@ -121,3 +129,100 @@ class MockedView:
         'set_index': value.set_index,
         'collection_index': value.collection_index,
     }, serializer)
+
+
+def test_serializer_create_checkbox(db):
+    value = Value.objects.get(
+        project_id=project_id,
+        snapshot=None,
+        attribute__path='individual/collection/checkbox',
+        collection_index=0
+    )
+    value2 = Value.objects.get(
+        project_id=project_id,
+        snapshot=None,
+        attribute__path='individual/collection/checkbox',
+        collection_index=2
+    )
+
+    class MockedRequest:
+        data = {
+            'widget_type': 'checkbox'
+        }
+
+    class MockedView:
+        request = MockedRequest()
+        project = Project.objects.get(id=project_id)
+
+    validator = ValueConflictValidator()
+    serializer = ValueSerializer()
+    serializer.context['view'] = MockedView()
+
+    validator({
+        'attribute': value.attribute,
+        'set_prefix': value.set_prefix,
+        'set_index': value.set_index,
+        'collection_index': value.collection_index,
+        'option': value2.option
+    }, serializer)
+
+
+def test_serializer_create_checkbox_error(db):
+    value = Value.objects.get(
+        project_id=project_id,
+        snapshot=None,
+        attribute__path='individual/collection/checkbox',
+        collection_index=0
+    )
+
+    class MockedRequest:
+        data = {
+            'widget_type': 'checkbox'
+        }
+
+    class MockedView:
+        request = MockedRequest()
+        project = Project.objects.get(id=project_id)
+
+    validator = ValueConflictValidator()
+    serializer = ValueSerializer()
+    serializer.context['view'] = MockedView()
+
+    with pytest.raises(RestFameworkValidationError):
+        validator({
+            'attribute': value.attribute,
+            'set_prefix': value.set_prefix,
+            'set_index': value.set_index,
+            'collection_index': value.collection_index,
+            'option': value.option
+        }, serializer)
+
+
+def test_serializer_create_checkbox_text(db):
+    value = Value.objects.get(
+        project_id=project_id,
+        snapshot=None,
+        attribute__path='individual/collection/checkbox',
+        collection_index=0
+    )
+
+    class MockedRequest:
+        data = {
+            'widget_type': 'text'
+        }
+
+    class MockedView:
+        request = MockedRequest()
+        project = Project.objects.get(id=project_id)
+
+    validator = ValueConflictValidator()
+    serializer = ValueSerializer()
+    serializer.context['view'] = MockedView()
+
+    with pytest.raises(RestFameworkValidationError):
+        validator({
+            'attribute': value.attribute,
+            'set_prefix': value.set_prefix,
+            'set_index': value.set_index,
+            'collection_index': value.collection_index
+        }, serializer)
diff --git a/rdmo/projects/validators.py b/rdmo/projects/validators.py
index 77c7495f3f..714b1c1287 100644
--- a/rdmo/projects/validators.py
+++ b/rdmo/projects/validators.py
@@ -28,13 +28,21 @@ def __call__(self, data, serializer):
                     })
         else:
             # for a new value, check if there is already a value with the same attribute and indexes
+            get_kwargs = {
+                'attribute': data.get('attribute'),
+                'set_prefix': data.get('set_prefix'),
+                'set_index': data.get('set_index'),
+                'collection_index': data.get('collection_index')
+            }
+
+            # for checkboxes, check only values with the same option
+            # get the widget_type from the put request
+            widget_type = serializer.context['view'].request.data.get('widget_type')
+            if widget_type == 'checkbox':
+                get_kwargs['option'] = data.get('option')
+
             try:
-                serializer.context['view'].project.values.filter(snapshot=None).get(
-                    attribute=data.get('attribute'),
-                    set_prefix=data.get('set_prefix'),
-                    set_index=data.get('set_index'),
-                    collection_index=data.get('collection_index')
-                )
+                serializer.context['view'].project.values.filter(snapshot=None).get(**get_kwargs)
             except ObjectDoesNotExist:
                 return
             except MultipleObjectsReturned: