diff --git a/addons/l10n_it_edi/models/account_edi_format.py b/addons/l10n_it_edi/models/account_edi_format.py
index 090e848edd5..9e2cf337281 100644
--- a/addons/l10n_it_edi/models/account_edi_format.py
+++ b/addons/l10n_it_edi/models/account_edi_format.py
@@ -330,7 +330,7 @@ class AccountEdiFormat(models.Model):
                     _logger.error('Error while receiving file from SdiCoop: %s', e)
 
     def _check_filename_is_fattura_pa(self, filename):
-        return re.search("([A-Z]{2}[A-Za-z0-9]{2,28}_[A-Za-z0-9]{0,5}.(xml.p7m|xml))", filename)
+        return re.search("[A-Z]{2}[A-Za-z0-9]{2,28}_[A-Za-z0-9]{0,5}.((?i:xml.p7m|xml))", filename)
 
     def _is_fattura_pa(self, filename, tree):
         return self.code == 'fattura_pa' and self._check_filename_is_fattura_pa(filename)