diff --git a/app/domain/people/data_quality_checker.rb b/app/domain/people/data_quality_checker.rb
new file mode 100644
index 000000000..d59c85aec
--- /dev/null
+++ b/app/domain/people/data_quality_checker.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+#  Copyright (c) 2024, Schweizer Alpen-Club. This file is part of
+#  hitobito_sac_cas and licensed under the Affero General Public License version 3
+#  or later. See the COPYING file at the top-level directory or at
+#  https://github.com/hitobito/hitobito_sac_cas
+
+class People::DataQualityChecker
+  ATTRIBUTES_TO_CHECK = %w[email street zip_code town first_name last_name
+    company_name phone_numbers birthday]
+
+  def initialize(person)
+    @person = person
+
+    check_invoice_recipient if @person.sac_membership_invoice?
+    check_stammsektion if @person.roles.exists?(type: SacCas::STAMMSEKTION_ROLES)
+
+    if @person.company?
+      check("warning", "company_name", "ist leer", invalid: @person.company_name.blank?)
+    else
+      check("error", "first_name", "ist leer", invalid: @person.first_name.blank?)
+      check("error", "last_name", "ist leer", invalid: @person.last_name.blank?)
+    end
+  end
+
+  private
+
+  def check_invoice_recipient
+    check("error", "street", "ist leer", invalid: @person.street.blank?)
+    check("error", "zip_code", "ist leer", invalid: @person.zip_code.blank?)
+    check("error", "town", "ist leer", invalid: @person.town.blank?)
+    check("warning", "email", "ist leer", invalid: @person.email.blank?)
+    check("warning", "phone_numbers", "sind leer", invalid: @person.phone_numbers.blank?)
+  end
+
+  def check_stammsektion
+    join_date = @person.roles.find_by(type: SacCas::STAMMSEKTION_ROLES).created_at
+
+    check("error", "birthday", "ist leer", invalid: @person.birthday.blank?)
+    check("warning", "birthday", "liegt weniger als 6 Jahre vor dem SAC-Eintritt",
+      invalid: @person.birthday.present? && (@person.birthday > join_date - 6.years))
+  end
+
+  def check(severity, attr, key, invalid: false)
+    if invalid
+      issue = @person.data_quality_issues.new(severity: severity, attr: attr, key: key)
+      issue.save! if issue.valid?
+    else
+      @person.data_quality_issues.find_by(severity: severity, attr: attr, key: key)&.destroy!
+    end
+  end
+end
diff --git a/app/models/person/data_quality_issue.rb b/app/models/person/data_quality_issue.rb
index 801c62167..6238b3d87 100644
--- a/app/models/person/data_quality_issue.rb
+++ b/app/models/person/data_quality_issue.rb
@@ -23,6 +23,8 @@
 #  index_person_data_quality_issues_on_person_and_attribute_and_key (key) UNIQUE
 
 class Person::DataQualityIssue < ApplicationRecord
+  VALID_ATTRIBUTES = Person.column_names + ["phone_numbers"]
+
   belongs_to :person
 
   enum severity: {info: 1, warning: 2, error: 3}
@@ -43,6 +45,6 @@ def message
   private
 
   def person_attribute_exists
-    errors.add(:attr, :invalid) unless Person.column_names.include?(attr)
+    errors.add(:attr, :invalid) unless VALID_ATTRIBUTES.include?(attr)
   end
 end
diff --git a/app/models/sac_cas/person.rb b/app/models/sac_cas/person.rb
index 3ea1ac175..bcd0a9aee 100644
--- a/app/models/sac_cas/person.rb
+++ b/app/models/sac_cas/person.rb
@@ -44,6 +44,7 @@ module SacCas::Person
     validates(*Person::SAC_REMARKS, format: {with: /\A[^\n\r]*\z/})
 
     before_save :set_digital_correspondence, if: :password_initialized?
+    after_save :check_data_quality
 
     delegate :salutation_label, to: :class
 
@@ -105,4 +106,12 @@ def data_quality
   def data_quality=(value)
     super(value.is_a?(Integer) ? value : DATA_QUALITIES.index(value.to_s))
   end
+
+  private
+
+  def check_data_quality
+    return if (People::DataQualityChecker::ATTRIBUTES_TO_CHECK & saved_changes.keys).empty?
+
+    People::DataQualityChecker.new(self)
+  end
 end