diff --git a/app/models/system_notification.rb b/app/models/system_notification.rb
index 6ebf69ff6..986cf5105 100644
--- a/app/models/system_notification.rb
+++ b/app/models/system_notification.rb
@@ -20,9 +20,12 @@ class SystemNotification < ApplicationRecord
             :source_created_at, :source_id, :last_time_changed_at,
             presence: true
 
-  validates :title, :description,
+  validates :title, :description, :modal_title,
             length: { maximum: Constants::NAME_MAX_LENGTH }
 
+  validates :modal_body,
+            length: { maximum: Constants::RICH_TEXT_MAX_LENGTH }
+
   def self.last_notifications(
     user,
     query = nil
diff --git a/spec/factories/system_notifications.rb b/spec/factories/system_notifications.rb
index 86e3c43e2..db2c23d14 100644
--- a/spec/factories/system_notifications.rb
+++ b/spec/factories/system_notifications.rb
@@ -3,7 +3,7 @@
 FactoryBot.define do
   factory :system_notification do
     sequence(:title) { |n| "System notification #{n}" }
-    description { Faker::ChuckNorris.fact }
+    description { Faker::ChuckNorris.fact[0..255] }
     modal_title { Faker::Name.first_name }
     modal_body { Faker::Lorem.paragraphs(4).map { |pr| "<p>#{pr}</p>" }.join }
     source_created_at { Faker::Time.between(3.days.ago, Date.today) }
diff --git a/spec/models/system_notification_spec.rb b/spec/models/system_notification_spec.rb
index 4410812f6..db03fadf4 100644
--- a/spec/models/system_notification_spec.rb
+++ b/spec/models/system_notification_spec.rb
@@ -13,18 +13,22 @@ describe SystemNotification do
   describe 'Validations' do
     describe '#title' do
       it { is_expected.to validate_presence_of(:title) }
+      it { is_expected.to validate_length_of(:title).is_at_most(255) }
     end
 
     describe '#modal_title' do
       it { is_expected.to validate_presence_of(:modal_title) }
+      it { is_expected.to validate_length_of(:modal_title).is_at_most(255) }
     end
 
     describe '#modal_body' do
       it { is_expected.to validate_presence_of(:modal_body) }
+      it { is_expected.to validate_length_of(:modal_body).is_at_most(50000) }
     end
 
     describe '#description' do
       it { is_expected.to validate_presence_of(:description) }
+      it { is_expected.to validate_length_of(:description).is_at_most(255) }
     end
 
     describe '#source_id' do