diff --git a/addons/website_slides/models/slide_channel.py b/addons/website_slides/models/slide_channel.py
index 449551fd9ab..c733e176118 100644
--- a/addons/website_slides/models/slide_channel.py
+++ b/addons/website_slides/models/slide_channel.py
@@ -105,7 +105,7 @@ class ChannelUsersRelation(models.Model):
                 continue
 
             email_values.update(
-                author_id=self.channel_id.user_id.partner_id.id or self.env.company.partner_id.id,
+                author_id=record.channel_id.user_id.partner_id.id or self.env.company.partner_id.id,
                 auto_delete=True,
                 recipient_ids=[(4, pid) for pid in email_values['partner_ids']],
             )
diff --git a/addons/website_slides/tests/test_slide_utils.py b/addons/website_slides/tests/test_slide_utils.py
index 6510b26cbd0..9fa7893fd71 100644
--- a/addons/website_slides/tests/test_slide_utils.py
+++ b/addons/website_slides/tests/test_slide_utils.py
@@ -42,6 +42,42 @@ class TestSlidesManagement(slides_common.SlidesCase):
             else:
                 self.assertTrue(slide.is_published, "All slides should be unpublished when a channel is archived, except categories")
 
+    def test_mail_completed(self):
+        """ When the slide.channel is completed, an email is supposed to be sent to people that completed it. """
+        channel_2 = self.env['slide.channel'].create({
+            'name': 'Test Course 2',
+            'slide_ids': [(0, 0, {
+                'name': 'Test Slide 1'
+            })]
+        })
+        all_users = self.user_officer | self.user_emp | self.user_portal
+        all_channels = self.channel | channel_2
+        all_channels.sudo()._action_add_members(all_users.partner_id)
+        slide_slide_vals = []
+        for slide in all_channels.slide_content_ids:
+            for user in self.user_officer | self.user_emp:
+                slide_slide_vals.append({
+                    'slide_id': slide.id,
+                    'channel_id': self.channel.id,
+                    'partner_id': user.partner_id.id,
+                    'completed': True
+                })
+        self.env['slide.slide.partner'].create(slide_slide_vals)
+        created_mails = self.env['mail.mail'].search([])
+
+        # 2 'congratulations' emails are supposed to be sent to user_officer and user_emp
+        for user in self.user_officer | self.user_emp:
+            self.assertTrue(
+                any(mail.model == 'slide.channel.partner' and user.partner_id in mail.recipient_ids
+                    for mail in created_mails)
+            )
+        # user_portal has not finished the course, it should not receive anything
+        self.assertFalse(
+            any(mail.model == 'slide.channel.partner' and self.user_portal.partner_id in mail.recipient_ids
+                for mail in created_mails)
+        )
+
+
 class TestSequencing(slides_common.SlidesCase):
 
     @users('user_officer')