diff --git a/app/models/derived_variables/sales_log_variables.rb b/app/models/derived_variables/sales_log_variables.rb
index 2b3542813..88bad228f 100644
--- a/app/models/derived_variables/sales_log_variables.rb
+++ b/app/models/derived_variables/sales_log_variables.rb
@@ -1,5 +1,10 @@
 module DerivedVariables::SalesLogVariables
   def set_derived_fields!
     self.ethnic = 17 if ethnic_refused?
+    if exdate.present?
+      self.exday = exdate.day
+      self.exmonth = exdate.month
+      self.exyear = exdate.year
+    end
   end
 end
diff --git a/app/models/form/sales/pages/exchange_date.rb b/app/models/form/sales/pages/exchange_date.rb
index 93b2e4742..59e23ab01 100644
--- a/app/models/form/sales/pages/exchange_date.rb
+++ b/app/models/form/sales/pages/exchange_date.rb
@@ -6,7 +6,7 @@ class Form::Sales::Pages::ExchangeDate < ::Form::Page
     @description = ""
     @subsection = subsection
     @depends_on = [{
-      "resale" => 2
+      "resale" => 2,
     }]
   end
 
diff --git a/spec/models/form/sales/pages/exchange_date_spec.rb b/spec/models/form/sales/pages/exchange_date_spec.rb
index d48a4b383..21c4c3aab 100644
--- a/spec/models/form/sales/pages/exchange_date_spec.rb
+++ b/spec/models/form/sales/pages/exchange_date_spec.rb
@@ -29,7 +29,7 @@ RSpec.describe Form::Sales::Pages::ExchangeDate, type: :model do
 
   it "has the correct depends_on" do
     expect(page.depends_on).to eq([{
-      "resale" => 2
+      "resale" => 2,
     }])
   end
 end
diff --git a/spec/models/sales_log_spec.rb b/spec/models/sales_log_spec.rb
index 3ee033971..9e618a10e 100644
--- a/spec/models/sales_log_spec.rb
+++ b/spec/models/sales_log_spec.rb
@@ -90,4 +90,19 @@ RSpec.describe SalesLog, type: :model do
       expect(described_class.filter_by_organisation([organisation_3]).count).to eq(0)
     end
   end
+
+  describe "derived variables" do
+    let!(:sales_log) do
+      described_class.create({
+        exdate: Time.gm(2022, 5, 4),
+      })
+    end
+
+    it "correctly derives and saves exday, exmonth and exyear" do
+      record_from_db = ActiveRecord::Base.connection.execute("select exday, exmonth, exyear from sales_logs where id=#{sales_log.id}").to_a[0]
+      expect(record_from_db["exday"]).to eq(4)
+      expect(record_from_db["exmonth"]).to eq(5)
+      expect(record_from_db["exyear"]).to eq(2022)
+    end
+  end
 end