diff --git a/app/scodoc/sco_groups.py b/app/scodoc/sco_groups.py
index 7a31b995b..120db6a43 100644
--- a/app/scodoc/sco_groups.py
+++ b/app/scodoc/sco_groups.py
@@ -806,8 +806,21 @@ def partition_create(
         )
 
     cnx = ndb.GetDBConnexion()
+    if numero is None:
+        numero = (
+            ndb.SimpleQuery(
+                "SELECT MAX(id) FROM partition WHERE formsemestre_id=%(formsemestre_id)s",
+                {"formsemestre_id": formsemestre_id},
+            ).fetchone()[0]
+            or 0
+        )
     partition_id = partitionEditor.create(
-        cnx, {"formsemestre_id": formsemestre_id, "partition_name": partition_name}
+        cnx,
+        {
+            "formsemestre_id": formsemestre_id,
+            "partition_name": partition_name,
+            "numero": numero,
+        },
     )
     log("createPartition: created partition_id=%s" % partition_id)
     #
@@ -1041,7 +1054,7 @@ def partition_move(partition_id, after=0, redirect=1):
     others = get_partitions_list(formsemestre_id)
     if len(others) > 1:
         pidx = [p["partition_id"] for p in others].index(partition_id)
-        log("partition_move: after=%s pidx=%s" % (after, pidx))
+        # log("partition_move: after=%s pidx=%s" % (after, pidx))
         neigh = None  # partition to swap with
         if after == 0 and pidx > 0:
             neigh = others[pidx - 1]
@@ -1049,8 +1062,20 @@ def partition_move(partition_id, after=0, redirect=1):
             neigh = others[pidx + 1]
         if neigh:  #
             # swap numero between partition and its neighbor
-            log("moving partition %s" % partition_id)
+            # log("moving partition %s" % partition_id)
             cnx = ndb.GetDBConnexion()
+            # Si aucun numéro n'a été affecté, le met au minimum
+            min_numero = (
+                ndb.SimpleQuery(
+                    "SELECT MIN(numero) FROM partition WHERE formsemestre_id=%(formsemestre_id)s",
+                    {"formsemestre_id": formsemestre_id},
+                ).fetchone()[0]
+                or 0
+            )
+            if neigh["numero"] is None:
+                neigh["numero"] = min_numero - 1
+            if partition["numero"] is None:
+                partition["numero"] = min_numero - 1 - after
             partition["numero"], neigh["numero"] = neigh["numero"], partition["numero"]
             partitionEditor.edit(cnx, partition)
             partitionEditor.edit(cnx, neigh)