diff --git a/accountant/api/views/accounts.py b/accountant/api/views/accounts.py
index 1eebb9c..c805f99 100644
--- a/accountant/api/views/accounts.py
+++ b/accountant/api/views/accounts.py
@@ -100,7 +100,7 @@ class AccountResource(Resource):
                 **kwargs
             ).filter(
                 Account.id == id
-            ).one()
+            ).one(), 200
         except NoResultFound:
             return None, 404
 
@@ -127,7 +127,7 @@ class AccountResource(Resource):
         # Return account with solds.
         return Account.query().filter(
             Account.id == id
-        ).one()
+        ).one(), 200
 
     @requires_auth
     @marshal_with_field(Object(resource_fields))
@@ -166,7 +166,7 @@ class CategoriesResource(Resource):
     def get(self):
         kwargs = range_parser.parse_args()
 
-        return Operation.get_categories_for_range(**kwargs).all()
+        return Operation.get_categories_for_range(**kwargs).all(), 200
 
 
 ohlc_resource_fields = {
@@ -184,7 +184,7 @@ class SoldsResource(Resource):
     def get(self):
         kwargs = range_parser.parse_args()
 
-        return Operation.get_ohlc_per_day_for_range(**kwargs).all()
+        return Operation.get_ohlc_per_day_for_range(**kwargs).all(), 200
 
 
 api_api.add_resource(CategoriesResource, "/categories")
diff --git a/accountant/api/views/operations.py b/accountant/api/views/operations.py
index 196a22e..36cea7d 100644
--- a/accountant/api/views/operations.py
+++ b/accountant/api/views/operations.py
@@ -74,7 +74,7 @@ class OperationListResource(Resource):
             end=kwargs['end'],
         ).filter(
             Operation.account_id == kwargs['account']
-        ).all()
+        ).all(), 200
 
     @requires_auth
     @marshal_with_field(Object(resource_fields))
@@ -85,7 +85,7 @@ class OperationListResource(Resource):
 
         db.session.add(operation)
 
-        return operation
+        return operation, 201
 
 
 class OperationResource(Resource):
@@ -100,7 +100,7 @@ class OperationResource(Resource):
         if not operation:
             return None, 404
 
-        return operation
+        return operation, 200
 
     @requires_auth
     @marshal_with_field(Object(resource_fields))
@@ -121,7 +121,7 @@ class OperationResource(Resource):
 
         db.session.merge(operation)
 
-        return operation
+        return operation, 200
 
     @requires_auth
     @marshal_with_field(Object(resource_fields))
@@ -133,7 +133,7 @@ class OperationResource(Resource):
 
         db.session.delete(operation)
 
-        return operation
+        return None, 204
 
 
 api_api.add_resource(OperationListResource, "/operations")
diff --git a/accountant/api/views/scheduled_operations.py b/accountant/api/views/scheduled_operations.py
index 8b487ba..1f6ff77 100644
--- a/accountant/api/views/scheduled_operations.py
+++ b/accountant/api/views/scheduled_operations.py
@@ -69,7 +69,7 @@ class ScheduledOperationListResource(Resource):
 
         return ScheduledOperation.query().filter(
             ScheduledOperation.account_id == kwargs.account
-        ).all()
+        ).all(), 200
 
     @marshal_with_field(Object(resource_fields))
     def post(self):
@@ -98,7 +98,7 @@ class ScheduledOperationResource(Resource):
         try:
             return ScheduledOperation.query().filter(
                 ScheduledOperation.id == id
-            ).one()
+            ).one(), 200
         except NoResultFound:
             return None, 404
 
@@ -129,7 +129,7 @@ class ScheduledOperationResource(Resource):
 
         db.session.flush()
 
-        return scheduled_operation
+        return scheduled_operation, 200
 
     @marshal_with_field(Object(resource_fields))
     def delete(self, id):