diff --git a/app/scodoc/sco_excel.py b/app/scodoc/sco_excel.py
index 6904062c..9698256f 100644
--- a/app/scodoc/sco_excel.py
+++ b/app/scodoc/sco_excel.py
@@ -35,7 +35,7 @@ from enum import Enum
 from tempfile import NamedTemporaryFile
 
 import openpyxl.utils.datetime
-from openpyxl.styles.numbers import FORMAT_NUMBER_00, FORMAT_GENERAL
+from openpyxl.styles.numbers import FORMAT_NUMBER_00, FORMAT_GENERAL, FORMAT_DATE_DDMMYY
 from openpyxl.comments import Comment
 from openpyxl import Workbook, load_workbook
 from openpyxl.cell import WriteOnlyCell
@@ -283,10 +283,6 @@ class ScoExcelSheet:
         style -- style par défaut (dictionnaire cf. excel_make_style) de la feuille si non spécifié
         """
         cell = WriteOnlyCell(self.ws, value or "")
-        if not (isinstance(value, int) or isinstance(value, float)):
-            cell.data_type = "s"
-        # if style is not None and "fill" in style:
-        #     toto()
         if style is None:
             style = self.default_style
         if "font" in style:
@@ -308,6 +304,14 @@ class ScoExcelSheet:
             lines = comment.splitlines()
             cell.comment.width = 7 * max([len(line) for line in lines])
             cell.comment.height = 20 * len(lines)
+        # test datatype at the end so that datetime format may be overwritten
+        if isinstance(value, datetime.date):
+            cell.data_type = "d"
+            cell.number_format = FORMAT_DATE_DDMMYY
+        elif isinstance(value, int) or isinstance(value, float):
+            cell.data_type = "n"
+        else:
+            cell.data_type = "s"
         return cell
 
     def make_row(self, values: list, style=None, comments=None):