diff --git a/tienda_ilusion/don_confiao/migrations/0040_customer_external_id.py b/tienda_ilusion/don_confiao/migrations/0040_customer_external_id.py
new file mode 100644
index 0000000..77d36aa
--- /dev/null
+++ b/tienda_ilusion/don_confiao/migrations/0040_customer_external_id.py
@@ -0,0 +1,18 @@
+# Generated by Django 5.0.6 on 2025-07-19 22:27
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('don_confiao', '0039_sale_external_id'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='customer',
+            name='external_id',
+            field=models.CharField(blank=True, max_length=100, null=True),
+        ),
+    ]
diff --git a/tienda_ilusion/don_confiao/models.py b/tienda_ilusion/don_confiao/models.py
index 1b30425..180e3af 100644
--- a/tienda_ilusion/don_confiao/models.py
+++ b/tienda_ilusion/don_confiao/models.py
@@ -17,6 +17,7 @@ class Customer(models.Model):
     address = models.CharField(max_length=100, null=True, blank=True)
     email = models.CharField(max_length=100, null=True, blank=True)
     phone = models.CharField(max_length=100, null=True, blank=True)
+    external_id = models.CharField(max_length=100, null=True, blank=True)
 
     def __str__(self):
         return self.name
diff --git a/tienda_ilusion/don_confiao/tests/test_party.py b/tienda_ilusion/don_confiao/tests/test_party.py
index 25d78e2..72c8a6f 100644
--- a/tienda_ilusion/don_confiao/tests/test_party.py
+++ b/tienda_ilusion/don_confiao/tests/test_party.py
@@ -14,6 +14,7 @@ class TestCustomer(TestCase):
         customer.save()
 
         self.assertIsInstance(customer, Customer)
+        self.assertIsNone(customer.external_id)
 
     def test_don_create_customer_without_name(self):
         customer = Customer()