diff --git a/app/models/organisation.rb b/app/models/organisation.rb
index e3e7f05c2..95f2b4a48 100644
--- a/app/models/organisation.rb
+++ b/app/models/organisation.rb
@@ -43,7 +43,7 @@ class Organisation < ApplicationRecord
 
   def local_authority_names
     names = local_authorities.map { |ons_code| LocalAuthority.ons_code_mappings[ons_code] }
-    names.present? ? names : ["All"]
+    names.presence || %w[All]
   end
 
   def rent_periods
@@ -52,7 +52,7 @@ class Organisation < ApplicationRecord
 
   def rent_period_labels
     labels = rent_periods.map { |period| RentPeriod.rent_period_mappings[period.to_s]["value"] }
-    labels.present? ? labels : ["All"]
+    labels.presence || %w[All]
   end
 
   def display_attributes
diff --git a/app/models/validations/financial_validations.rb b/app/models/validations/financial_validations.rb
index a95cf25c1..857ceb45a 100644
--- a/app/models/validations/financial_validations.rb
+++ b/app/models/validations/financial_validations.rb
@@ -80,6 +80,17 @@ module Validations::FinancialValidations
     validate_rent_range(record)
   end
 
+  def validate_rent_period(record)
+    if record.owning_organisation.present? && record.owning_organisation.rent_periods.present? &&
+        record.period && !record.owning_organisation.rent_periods.include?(record.period)
+      record.errors.add :period, I18n.t(
+        "validations.financial.rent_period.invalid_for_org",
+        org_name: record.owning_organisation.name,
+        rent_period: record.form.get_question("period", record).label_from_value(record.period).downcase,
+      )
+    end
+  end
+
 private
 
   CHARGE_MAXIMUMS = {
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 2d66ac916..ab1c95918 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -138,6 +138,8 @@ en:
         complete_1_of_3: "Answer either the ‘household rent and charges’ question or 'is this accommodation a care home', or select ‘no’ for ‘does the household pay rent or charges for the accommodation?’"
       tcharge:
         under_10: "Total charge must be at least £10 per week"
+      rent_period:
+        invalid_for_org: "%{org_name} does not charge rent %{rent_period}"
 
     household:
       reasonpref:
diff --git a/spec/factories/organisation.rb b/spec/factories/organisation.rb
index 7da708cae..981217736 100644
--- a/spec/factories/organisation.rb
+++ b/spec/factories/organisation.rb
@@ -18,7 +18,7 @@ FactoryBot.define do
 
   factory :organisation_rent_period do
     organisation
-    rent_period { 1 }
+    rent_period { 2 }
     created_at { Time.zone.now }
     updated_at { Time.zone.now }
   end
diff --git a/spec/models/case_log_spec.rb b/spec/models/case_log_spec.rb
index 3633fba51..852b2eaec 100644
--- a/spec/models/case_log_spec.rb
+++ b/spec/models/case_log_spec.rb
@@ -125,6 +125,10 @@ RSpec.describe CaseLog do
       expect(validator).to receive(:validate_outstanding_rent_amount)
     end
 
+    it "validates the rent period" do
+      expect(validator).to receive(:validate_rent_period)
+    end
+
     it "validates housing benefit rent shortfall" do
       expect(validator).to receive(:validate_tshortfall)
     end
diff --git a/spec/models/validations/financial_validations_spec.rb b/spec/models/validations/financial_validations_spec.rb
index 68b5f4629..7f4eb438c 100644
--- a/spec/models/validations/financial_validations_spec.rb
+++ b/spec/models/validations/financial_validations_spec.rb
@@ -86,6 +86,28 @@ RSpec.describe Validations::FinancialValidations do
     end
   end
 
+  describe "rent period validations" do
+    let(:organisation) { FactoryBot.create(:organisation) }
+    let(:record) { FactoryBot.create(:case_log, owning_organisation: organisation) }
+
+    before do
+      FactoryBot.create(:organisation_rent_period, organisation:, rent_period: 2)
+    end
+
+    context "when the organisation only uses specific rent periods" do
+      it "validates that the selected rent period is used by the organisation" do
+        record.period = 3
+        financial_validator.validate_rent_period(record)
+        expect(record.errors["period"])
+          .to include(match I18n.t(
+            "validations.financial.rent_period.invalid_for_org",
+            org_name: organisation.name,
+            rent_period: "every 2 weeks",
+          ))
+      end
+    end
+  end
+
   describe "housing benefit rent shortfall validations" do
     context "when shortfall is yes" do
       it "validates that housing benefit is not none" do
@@ -121,7 +143,7 @@ RSpec.describe Validations::FinancialValidations do
     end
   end
 
-  describe "Net income validations" do
+  describe "net income validations" do
     it "validates that the net income is within the expected range for the tenant's employment status" do
       record.earnings = 200
       record.incfreq = 1