diff --git a/app/models/invite.rb b/app/models/invite.rb
index e0bd78ad6ff..2aa7c91f6fd 100644
--- a/app/models/invite.rb
+++ b/app/models/invite.rb
@@ -32,8 +32,9 @@ class Invite < ActiveRecord::Base
   has_many :topics, through: :topic_invites, source: :topic
 
   validates_presence_of :invited_by_id
-  validates :email, email: true, allow_blank: true
+  validates :email, email: true, allow_blank: true, length: { maximum: 500 }
   validates :custom_message, length: { maximum: 1000 }
+  validates :domain, length: { maximum: 500 }
   validate :ensure_max_redemptions_allowed
   validate :valid_redemption_count
   validate :valid_domain, if: :will_save_change_to_domain?
@@ -350,7 +351,7 @@ class Invite < ActiveRecord::Base
     self.domain.downcase!
 
     if self.domain !~ Invite::DOMAIN_REGEX
-      self.errors.add(:base, I18n.t("invite.domain_not_allowed"))
+      self.errors.add(:base, I18n.t("invite.domain_not_allowed_admin"))
     end
   end
 
diff --git a/config/locales/server.en.yml b/config/locales/server.en.yml
index 3a815f4d86d..3cd66cc11de 100644
--- a/config/locales/server.en.yml
+++ b/config/locales/server.en.yml
@@ -342,6 +342,7 @@ en:
     requires_groups: "Invite was not saved because the specified topic is inaccessible. Add one of the following groups: %{groups}."
     max_invite_emails_limit_exceeded: "Request failed because number of emails exceeded the maximum (%{max})."
     domain_not_allowed: "Your email cannot be used to redeem this invite."
+    domain_not_allowed_admin: "This domain cannot be used for invites."
     max_redemptions_allowed_one: "for email invites should be 1."
     redemption_count_less_than_max: "should be less than %{max_redemptions_allowed}."
     email_xor_domain: "Email and domain fields are not allowed at the same time"
diff --git a/spec/requests/invites_controller_spec.rb b/spec/requests/invites_controller_spec.rb
index 534d11354d1..2fd40b192de 100644
--- a/spec/requests/invites_controller_spec.rb
+++ b/spec/requests/invites_controller_spec.rb
@@ -433,6 +433,18 @@ RSpec.describe InvitesController do
         end
       end
 
+      context "when email address is too long" do
+        let(:email) { "a" * 495 + "@example.com" }
+
+        it "fails" do
+          create_invite
+          expect(response).to have_http_status :unprocessable_entity
+          expect(response.parsed_body["errors"]).to be_present
+          error_message = response.parsed_body["errors"].first
+          expect(error_message).to eq("Email is too long (maximum is 500 characters)")
+        end
+      end
+
       context "when providing an email belonging to an existing user" do
         let(:email) { user.email }
 
@@ -460,6 +472,46 @@ RSpec.describe InvitesController do
       end
     end
 
+    context "with domain invite" do
+      it "works" do
+        sign_in(admin)
+
+        post "/invites.json", params: { domain: "example.com" }
+        expect(response).to have_http_status :ok
+      end
+
+      it "fails when domain is invalid" do
+        sign_in(admin)
+
+        post "/invites.json", params: { domain: "example" }
+
+        expect(response).to have_http_status :unprocessable_entity
+
+        error_message = response.parsed_body["errors"].first
+        expect(error_message).to eq(I18n.t("invite.domain_not_allowed_admin"))
+      end
+
+      it "fails when domain is too long" do
+        sign_in(admin)
+
+        post "/invites.json", params: { domain: "a" * 500 + ".ca" }
+        expect(response).to have_http_status :unprocessable_entity
+
+        error_message = response.parsed_body["errors"].first
+        expect(error_message).to eq("Domain is too long (maximum is 500 characters)")
+      end
+
+      it "fails when custom message is too long" do
+        sign_in(admin)
+
+        post "/invites.json", params: { custom_message: "b" * 1001, domain: "example.com" }
+        expect(response).to have_http_status :unprocessable_entity
+
+        error_message = response.parsed_body["errors"].first
+        expect(error_message).to eq("Custom message is too long (maximum is 1000 characters)")
+      end
+    end
+
     context "with link invite" do
       it "works" do
         sign_in(admin)