diff --git a/lib/open_project/costs/engine.rb b/lib/open_project/costs/engine.rb
index 29d8c51ab9..e436f98c0a 100644
--- a/lib/open_project/costs/engine.rb
+++ b/lib/open_project/costs/engine.rb
@@ -173,16 +173,19 @@ module OpenProject::Costs
       property :labor_costs,
                exec_context: :decorator,
                if: ->(*) { labor_costs_visible? },
+               skip_parse: true,
                render_nil: true
 
       property :material_costs,
                exec_context: :decorator,
                if: ->(*) { material_costs_visible? },
+               skip_parse: true,
                render_nil: true
 
       property :overall_costs,
                exec_context: :decorator,
                if: ->(*) { overall_costs_visible? },
+               skip_parse: true,
                render_nil: true
 
       resource :costsByType,