diff --git a/taiga/projects/contact/permissions.py b/taiga/projects/contact/permissions.py
index 678aede9..2898e347 100644
--- a/taiga/projects/contact/permissions.py
+++ b/taiga/projects/contact/permissions.py
@@ -22,7 +22,13 @@ from taiga.base.api.permissions import TaigaResourcePermission
 
 class IsContactActivated(PermissionComponent):
     def check_permissions(self, request, view, obj=None):
-        return request.user.is_authenticated() and obj.project.is_contact_activated
+        if not request.user.is_authenticated() or not obj.project.is_contact_activated:
+            return False
+
+        if obj.project.is_private:
+            return obj.project.cached_memberships_for_user(request.user)
+
+        return True
 
 
 class ContactPermission(TaigaResourcePermission):
diff --git a/tests/integration/resources_permissions/test_contact.py b/tests/integration/resources_permissions/test_contact.py
index 7b5a1bec..c21adbc8 100644
--- a/tests/integration/resources_permissions/test_contact.py
+++ b/tests/integration/resources_permissions/test_contact.py
@@ -32,7 +32,7 @@ pytestmark = pytest.mark.django_db
 def data():
     m = type("Models", (object,), {})
     m.user = f.UserFactory.create()
-    m.project = f.ProjectFactory.create()
+    m.project = f.ProjectFactory.create(is_private=False)
     f.MembershipFactory(user=m.project.owner, project=m.project, is_admin=True)
 
     return m
diff --git a/tests/integration/test_contact.py b/tests/integration/test_contact.py
index 600b40f7..cb774afa 100644
--- a/tests/integration/test_contact.py
+++ b/tests/integration/test_contact.py
@@ -28,12 +28,15 @@ import pytest
 pytestmark = pytest.mark.django_db
 
 
-def test_create_comment(client):
+# Members can comment on a private project
+# if the project has the contact activated
+def test_member_create_comment_on_private_project(client):
     user = f.UserFactory.create()
-    project = f.ProjectFactory.create()
+    project = f.ProjectFactory.create(is_private=True)
+    project.is_contact_activated = True
     m1 = f.MembershipFactory(user=project.owner, project=project)
     m2 = f.MembershipFactory(project=project, is_admin=True)
-    m3 = f.MembershipFactory(project=project, is_admin=False)
+    m3 = f.MembershipFactory(user=user, project=project, is_admin=False)
 
     url = reverse("contact-list")
 
@@ -51,7 +54,53 @@ def test_create_comment(client):
     assert set(mail.outbox[0].to[0].split(", ")) == set([project.owner.email, m2.user.email])
 
 
+# Non members user cannot comment on a private project
+# even if the project has the contact activated
+def test_guest_create_comment_on_private_project(client):
+    user = f.UserFactory.create()
+    project = f.ProjectFactory.create(is_private=True)
+    project.is_contact_activated = True
 
+    url = reverse("contact-list")
+
+    contact_data = json.dumps({
+        "project": project.id,
+        "comment": "Testing comment"
+    })
+
+    client.login(user)
+
+    response = client.post(url, contact_data, content_type="application/json")
+    assert response.status_code == 403
+    assert len(mail.outbox) == 0
+
+
+# All user can comment on a public project
+# if the project has the contact activated
+def test_create_comment_on_public_project(client):
+    user = f.UserFactory.create()
+    project = f.ProjectFactory.create(is_private=False)
+    project.is_contact_activated = True
+    m1 = f.MembershipFactory(user=project.owner, project=project)
+    m2 = f.MembershipFactory(project=project, is_admin=True)
+    url = reverse("contact-list")
+
+    contact_data = json.dumps({
+        "project": project.id,
+        "comment": "Testing comment"
+    })
+
+    client.login(user)
+
+    assert len(mail.outbox) == 0
+    response = client.post(url, contact_data, content_type="application/json")
+    assert response.status_code == 201
+    assert len(mail.outbox) == 1
+    assert set(mail.outbox[0].to[0].split(", ")) == set([project.owner.email, m2.user.email])
+
+
+# No user can comment on a project
+# if the project does not have the contact activated
 def test_create_comment_disabled(client):
     user = f.UserFactory.create()
     project = f.ProjectFactory.create()