diff --git a/aleksis/core/preferences.py b/aleksis/core/preferences.py
index 4de9d9e411fc9ee888d5650d48b0f4adfa916d87..fe29f220f211616bf57d08c04e87a95b60c84365 100644
--- a/aleksis/core/preferences.py
+++ b/aleksis/core/preferences.py
@@ -41,6 +41,7 @@ class SiteTitle(StringPreference):
     name = "title"
     default = "AlekSIS"
     verbose_name = _("Site title")
+    required = True
 
 
 @site_preferences_registry.register
@@ -63,6 +64,7 @@ class ColourPrimary(StringPreference):
     default = "#0d5eaf"
     verbose_name = _("Primary colour")
     widget = ColorWidget
+    required = True
 
 
 @site_preferences_registry.register
@@ -74,6 +76,7 @@ class ColourSecondary(StringPreference):
     default = "#0d5eaf"
     verbose_name = _("Secondary colour")
     widget = ColorWidget
+    required = True
 
 
 @site_preferences_registry.register
@@ -84,6 +87,7 @@ class Logo(PublicFilePreferenceMixin, FilePreference):
     field_class = ImageField
     name = "logo"
     verbose_name = _("Logo")
+    required = False
 
 
 @site_preferences_registry.register
@@ -94,6 +98,7 @@ class Favicon(PublicFilePreferenceMixin, FilePreference):
     field_class = ImageField
     name = "favicon"
     verbose_name = _("Favicon")
+    required = False
 
 
 @site_preferences_registry.register
@@ -104,6 +109,7 @@ class PWAIcon(PublicFilePreferenceMixin, FilePreference):
     field_class = ImageField
     name = "pwa_icon"
     verbose_name = _("PWA-Icon")
+    required = False
 
 
 @site_preferences_registry.register
@@ -114,6 +120,7 @@ class MailOutName(StringPreference):
     name = "name"
     default = "AlekSIS"
     verbose_name = _("Mail out name")
+    required = True
 
 
 @site_preferences_registry.register
@@ -125,6 +132,7 @@ class MailOut(StringPreference):
     default = settings.DEFAULT_FROM_EMAIL
     verbose_name = _("Mail out address")
     field_class = EmailField
+    required = True
 
 
 @site_preferences_registry.register
@@ -163,6 +171,7 @@ class AdressingNameFormat(ChoicePreference):
         ("first_last", "John Doe"),
         ("last_fist", "Doe, John"),
     )
+    required = True
 
 
 @person_preferences_registry.register
@@ -308,6 +317,7 @@ class AvailableLanguages(MultipleChoicePreference):
     verbose_name = _("Available languages")
     field_attribute = {"initial": []}
     choices = settings.LANGUAGES
+    required = True
 
 
 @site_preferences_registry.register