diff --git a/app/models/validations/sales/sale_information_validations.rb b/app/models/validations/sales/sale_information_validations.rb
index f34eec790..378943f3a 100644
--- a/app/models/validations/sales/sale_information_validations.rb
+++ b/app/models/validations/sales/sale_information_validations.rb
@@ -134,6 +134,12 @@ module Validations::Sales::SaleInformationValidations
     end
   end
 
+  def validate_purchase_amount(record)
+    return unless record.value && record.value > 999_999
+
+    record.errors.add :value, I18n.t("validations.sales.sale_information.value.purchase_price_out_of_range")
+  end
+
   def validate_grant_amount(record)
     return unless record.saledate && record.form.start_year_2024_or_later?
     return unless record.grant && (record.type == 8 || record.type == 21)
@@ -143,6 +149,12 @@ module Validations::Sales::SaleInformationValidations
     end
   end
 
+  def validate_mortgage_amount(record)
+    return unless record.mortgage && record.mortgage > 999_999
+
+    record.errors.add :mortgage, I18n.t("validations.sales.sale_information.mortgage.mortgage_out_of_range")
+  end
+
   def validate_stairbought(record)
     return unless record.stairbought && record.type
     return unless record.saledate && record.form.start_year_2024_or_later?
diff --git a/config/locales/validations/sales/sale_information.en.yml b/config/locales/validations/sales/sale_information.en.yml
index 3c39608cc..ff2721bbc 100644
--- a/config/locales/validations/sales/sale_information.en.yml
+++ b/config/locales/validations/sales/sale_information.en.yml
@@ -53,6 +53,7 @@ en:
           staircasing_mortgage:
             mortgage_used: "The mortgage (%{mortgage}) and cash deposit (%{deposit}) added together is %{mortgage_and_deposit_total}.</br></br>The full purchase price (%{value}) multiplied by the percentage bought is %{stairbought_part_of_value}.</br></br>These two amounts should be the same."
             mortgage_used_socialhomebuy: "The mortgage amount (%{mortgage}), cash deposit (%{deposit}), and cash discount (%{cashdis}) added together is %{mortgage_deposit_and_discount_total}.</br></br>The full purchase price (%{value}) multiplied by the percentage bought (%{stairbought}) is %{stairbought_part_of_value}.</br></br>These two amounts should be the same."
+          mortgage_out_of_range: "Mortgage amount must be between £0 and £999,999."
         value:
           discounted_ownership_value: "The mortgage%{mortgage}%{deposit_and_grant_sentence} added together is %{mortgage_deposit_and_grant_total}.</br></br>The full purchase price%{discount_sentence} is %{value_with_discount}.</br></br>These two amounts should be the same."
           outright_sale_value: "The mortgage%{mortgage} and cash deposit (%{deposit}) when added together is %{mortgage_and_deposit_total}.</br></br>The full purchase price is %{value}.</br></br>These two amounts should be the same."
@@ -68,6 +69,7 @@ en:
             mortgage_not_used: "The cash deposit is %{deposit}.</br></br>The full purchase price (%{value}) multiplied by the percentage bought is %{stairbought_part_of_value}.</br></br>These two amounts should be the same."
             mortgage_used_socialhomebuy: "The mortgage amount (%{mortgage}), cash deposit (%{deposit}), and cash discount (%{cashdis}) added together is %{mortgage_deposit_and_discount_total}.</br></br>The full purchase price (%{value}) multiplied by the percentage bought (%{stairbought}) is %{stairbought_part_of_value}.</br></br>These two amounts should be the same."
             mortgage_not_used_socialhomebuy: "The cash deposit (%{deposit}) and cash discount (%{cashdis}) added together is %{deposit_and_discount_total}.</br></br>The full purchase price (%{value}) multiplied by the percentage bought (%{stairbought}) is %{stairbought_part_of_value}.</br></br>These two amounts should be the same."
+          purchase_price_out_of_range: "Purchase price must be between £0 and £999,999."
         deposit:
           discounted_ownership_value: "The mortgage%{mortgage}%{deposit_and_grant_sentence} added together is %{mortgage_deposit_and_grant_total}.</br></br>The full purchase price%{discount_sentence} is %{value_with_discount}.</br></br>These two amounts should be the same."
           outright_sale_value: "The mortgage%{mortgage} and cash deposit (%{deposit}) when added together is %{mortgage_and_deposit_total}.</br></br>The full purchase price is %{value}.</br></br>These two amounts should be the same."