diff --git a/grocy_importer.py b/grocy_importer.py
index 8f9cd6c..3eecde2 100755
--- a/grocy_importer.py
+++ b/grocy_importer.py
@@ -393,6 +393,16 @@ def get_user_fields(self, entity: str, object_id: int) -> GrocyUserFields:
         self.assert_valid_response(response)
         return cast(GrocyUserFields, response.json())
 
+    def set_userfields(self, entity: str, object_id: int,
+                       user_fields: dict[str, object]) -> None:
+        ''' Sets a Grocy user field '''
+        call = f'/userfields/{entity}/{object_id}'
+        response = requests.put(self.base_url + call,
+                                headers=self.headers,
+                                timeout=self.timeout,
+                                data=json.dumps(user_fields))
+        self.assert_valid_response(response)
+
 
 @dataclass
 class AppArgs:
@@ -420,6 +430,7 @@ class CliArgs(AppArgs):
     days: int
     at: Optional[GrocyDateTime]
     keep: Literal['later', 'earlier', 'old', 'new']
+    entity: str
 
 
 @dataclass
@@ -1270,6 +1281,26 @@ def todotxt_chore_push(args: TodotxtArgs,
                       f' on {response["tracked_time"]}')
 
 
+def userfield_cmd(args: CliArgs,
+                  _: AppConfig,
+                  grocy: GrocyApi) -> None:
+    ''' Quickly add userfields '''
+    try:
+        for item in yaml.safe_load(args.file):
+            try:
+                item_id = item['id']
+                del item['id']
+                grocy.set_userfields(args.entity, item_id, item)
+                print(f'{args.entity} {item_id}')
+            except KeyError:
+                print('Error: missing id-field for entity in yaml file.',
+                      file=sys.stderr)
+    except TypeError:
+        print('Error: list missing in yaml file.', file=sys.stderr)
+    except yaml.scanner.ScannerError:
+        print('Error: yaml invalid.', file=sys.stderr)
+
+
 def chore_show_cmd(args: AppArgs,
                    _: AppConfig,
                    grocy: GrocyApi,
@@ -1456,6 +1487,20 @@ def get_argparser_cli(stores: Iterable[Store]) -> ArgumentParser:
                                   help='Show given chore')
     chore_show.set_defaults(func=chore_show_cmd)
     add_chore_show_arguments(chore_show)
+    userfield = subparsers.add_parser('userfield',
+                                      description='Add userfield(s) to'
+                                                  ' (usally) many grocy'
+                                                  ' entities from a yaml'
+                                                  ' file.',
+                                      help='Quickly add userfields')
+    userfield.set_defaults(func=userfield_cmd)
+    userfield.add_argument('entity',
+                           help='the type of entity that the user fields'
+                                ' should be added to. E.g. batteries, chores,'
+                                ' chores_log, ...')
+    userfield.add_argument('file',
+                           type=FileType('r', encoding='utf-8'),
+                           help='a yaml file with the user fields to set')
     return parser
 
 
diff --git a/tests/README.rst b/tests/README.rst
index 5a7179b..dc3ce2a 100644
--- a/tests/README.rst
+++ b/tests/README.rst
@@ -11,17 +11,19 @@ we only include cases that are not useful there.
 
     $ grocy_importer.py --help
     usage: grocy_importer.py [-h] [--timeout N] [--dry-run]
-                             {whereis,shopping-list,recipe,purchase,chore} ...
+                             {whereis,shopping-list,recipe,purchase,chore,userfield}
+                             ...
     
     Help importing into Grocy
     
     positional arguments:
-      {whereis,shopping-list,recipe,purchase,chore}
+      {whereis,shopping-list,recipe,purchase,chore,userfield}
         whereis             show location of a product
         shopping-list       export shopping list in todo.txt format
         recipe              assist importing recipes from the web
         purchase            import purchases
         chore               Prompt to do each overdue chore
+        userfield           Quickly add userfields
     
     options:
       -h, --help            show this help message and exit
@@ -73,3 +75,77 @@ Recipe
     
     Unknown unit convertion:
     
+
+Userfields
+----------
+
+.. code::
+
+    $ grocy_importer.py userfield --help
+    usage: grocy_importer.py userfield [-h] entity file
+    
+    Add userfield(s) to (usally) many grocy entities from a yaml file.
+    
+    positional arguments:
+      entity      the type of entity that the user fields should be added to. E.g.
+                  batteries, chores, chores_log, ...
+      file        a yaml file with the user fields to set
+    
+    options:
+      -h, --help  show this help message and exit
+
+.. code::
+
+    $ cat tests/userfields.yml
+    ---
+    - id: 1
+      customfield1: Changed entity1, field 1
+    - id: 2
+      customfield1: Changed entity2, field 2
+      customfield2: Changed entity2, field 2
+
+In addition to the user fields that should be set only the id of the entity for the fields needs to be specified.
+
+.. code::
+
+    $ grocy_importer.py userfield userentity-exampleuserentity tests/userfields.yml
+    userentity-exampleuserentity 1
+    userentity-exampleuserentity 2
+
+In case the userfields doesn't match the entity an error will be printed:
+
+.. code::
+
+    $ grocy_importer.py userfield chores tests/userfields.yml
+    Error: Connection to Grocy failed with Bad Request: Field customfield1 is not a valid userfield of the given entity
+
+In case the entity id doesn't exist, we would hope that grocy would complain with an error. Instead it just saves the userfields.
+
+.. code::
+
+    $ grocy_importer.py userfield userentity-exampleuserentity tests/userfields-missing-entity.yml
+    userentity-exampleuserentity 10001
+    userentity-exampleuserentity 2
+
+In case the given file isn't a yml an error will be printed:
+
+.. code::
+
+    $ grocy_importer.py userfield userentity-exampleuserentity tests/README.rst
+    Error: yaml invalid.
+
+In case the id of an item is missing an error will be printed:
+
+.. code::
+
+    $ grocy_importer.py userfield userentity-exampleuserentity tests/userfields-missing-id.yml
+    Error: missing id-field for entity in yaml file.
+    userentity-exampleuserentity 2
+
+In case the given list is empty
+
+.. code::
+
+    $ grocy_importer.py userfield userentity-exampleuserentity /dev/null
+    Error: list missing in yaml file.
+
diff --git a/tests/userfields-missing-entity.yml b/tests/userfields-missing-entity.yml
new file mode 100644
index 0000000..4366f1f
--- /dev/null
+++ b/tests/userfields-missing-entity.yml
@@ -0,0 +1,6 @@
+---
+- id: 10001
+  customfield1: ignored as entity-id missing
+- id: 2
+  customfield1: Changed entity2, field 2
+  customfield2: Changed entity2, field 2
diff --git a/tests/userfields-missing-id.yml b/tests/userfields-missing-id.yml
new file mode 100644
index 0000000..bb21174
--- /dev/null
+++ b/tests/userfields-missing-id.yml
@@ -0,0 +1,5 @@
+---
+- customfield1: Changed entity1, field 1
+- id: 2
+  customfield1: Changed entity2, field 2
+  customfield2: Changed entity2, field 2
diff --git a/tests/userfields.yml b/tests/userfields.yml
new file mode 100644
index 0000000..80772f4
--- /dev/null
+++ b/tests/userfields.yml
@@ -0,0 +1,6 @@
+---
+- id: 1
+  customfield1: Changed entity1, field 1
+- id: 2
+  customfield1: Changed entity2, field 2
+  customfield2: Changed entity2, field 2