diff --git a/app/services/bulk_upload/sales/year2023/row_parser.rb b/app/services/bulk_upload/sales/year2023/row_parser.rb
index 57de4300e..93f15395f 100644
--- a/app/services/bulk_upload/sales/year2023/row_parser.rb
+++ b/app/services/bulk_upload/sales/year2023/row_parser.rb
@@ -243,13 +243,13 @@ class BulkUpload::Sales::Year2023::RowParser
   attribute :field_75, :integer
   attribute :field_76, :integer
   attribute :field_77, :integer
-  attribute :field_78, :integer
+  attribute :field_78, :string
   attribute :field_79, :integer
-  attribute :field_80, :integer
+  attribute :field_80, :string
 
   attribute :field_81, :integer
   attribute :field_82, :integer
-  attribute :field_83, :integer
+  attribute :field_83, :string
   attribute :field_84, :integer
   attribute :field_85, :integer
   attribute :field_86, :integer
@@ -841,17 +841,17 @@ private
     attributes["ethnic"] = field_32
     attributes["national"] = field_33
 
-    attributes["income1nk"] = field_78.present? ? 0 : 1
-    attributes["income1"] = field_78
+    attributes["income1nk"] = field_78 == "R" ? 1 : 0
+    attributes["income1"] = field_78.to_i if attributes["income1nk"]&.zero? && field_78&.match(/\A\d+\z/)
 
-    attributes["income2nk"] = field_80.present? ? 0 : 1
-    attributes["income2"] = field_80
+    attributes["income2nk"] = field_80 == "R" ? 1 : 0
+    attributes["income2"] = field_80.to_i if attributes["income2nk"]&.zero? && field_80&.match(/\A\d+\z/)
 
     attributes["inc1mort"] = field_79
     attributes["inc2mort"] = field_81
 
-    attributes["savingsnk"] = field_83.present? ? 0 : 1
-    attributes["savings"] = field_83
+    attributes["savingsnk"] = field_83 == "R" ? 1 : 0
+    attributes["savings"] = field_83.to_i if attributes["savingsnk"]&.zero? && field_83&.match(/\A\d+\z/)
     attributes["prevown"] = field_84
 
     attributes["prevten"] = field_62
diff --git a/spec/services/bulk_upload/sales/year2023/row_parser_spec.rb b/spec/services/bulk_upload/sales/year2023/row_parser_spec.rb
index 6f617b584..1056d4402 100644
--- a/spec/services/bulk_upload/sales/year2023/row_parser_spec.rb
+++ b/spec/services/bulk_upload/sales/year2023/row_parser_spec.rb
@@ -182,6 +182,54 @@ RSpec.describe BulkUpload::Sales::Year2023::RowParser do
     end
   end
 
+  describe "income and savings fields" do
+    context "when set to R" do
+      let(:attributes) do
+        {
+          bulk_upload:,
+          field_78: "R", # income 1
+          field_80: "R", # income 2
+          field_83: "R", # savings
+        }
+      end
+
+      it "sets the not known field as not known" do
+        expect(parser.log.income1nk).to be(1)
+        expect(parser.log.income2nk).to be(1)
+        expect(parser.log.savingsnk).to be(1)
+      end
+
+      it "leaves the value field nil" do
+        expect(parser.log.income1).to be_nil
+        expect(parser.log.income2).to be_nil
+        expect(parser.log.savings).to be_nil
+      end
+    end
+
+    context "when set to a number" do
+      let(:attributes) do
+        {
+          bulk_upload:,
+          field_78: "30000", # income 1
+          field_80: "0", # income 2
+          field_83: "12420", # savings
+        }
+      end
+
+      it "sets the not known field as known" do
+        expect(parser.log.income1nk).to be(0)
+        expect(parser.log.income2nk).to be(0)
+        expect(parser.log.savingsnk).to be(0)
+      end
+
+      it "sets the values" do
+        expect(parser.log.income1).to be(30_000)
+        expect(parser.log.income2).to be(0)
+        expect(parser.log.savings).to be(12_420)
+      end
+    end
+  end
+
   describe "validations" do
     before do
       stub_request(:get, /api.postcodes.io/)