diff --git a/app/javascript/controllers/format_controller.ts b/app/javascript/controllers/format_controller.ts
index da1dcacce..f5ce0227d 100644
--- a/app/javascript/controllers/format_controller.ts
+++ b/app/javascript/controllers/format_controller.ts
@@ -54,6 +54,6 @@ export class FormatController extends ApplicationController {
     const decimalSeparator =
       value.lastIndexOf(',') > value.lastIndexOf('.') ? ',' : '.';
 
-    return value.replace(new RegExp(`[^\\d${decimalSeparator}]`, 'g'), '');
+    return value.replace(new RegExp(`[^-?\\d${decimalSeparator}]`, 'g'), '');
   }
 }
diff --git a/spec/system/users/brouillon_spec.rb b/spec/system/users/brouillon_spec.rb
index f0cb9c2c4..d5ca28594 100644
--- a/spec/system/users/brouillon_spec.rb
+++ b/spec/system/users/brouillon_spec.rb
@@ -199,6 +199,11 @@ describe 'The user' do
     wait_until {
       champ_value_for('nombre décimal') == '1234.56'
     }
+
+    fill_in('nombre décimal', with: '-1,234.56')
+    wait_until {
+      champ_value_for('nombre décimal') == '-1234.56'
+    }
   end
 
   scenario 'extends dossier experation date more than one time, ', js: true, retry: 3 do