diff --git a/app/services/bulk_upload/lettings/validator.rb b/app/services/bulk_upload/lettings/validator.rb
index 1a0e6ecf5..e78c1138b 100644
--- a/app/services/bulk_upload/lettings/validator.rb
+++ b/app/services/bulk_upload/lettings/validator.rb
@@ -9,8 +9,8 @@ class BulkUpload::Lettings::Validator
   attr_reader :bulk_upload, :path
 
   validate :validate_file_not_empty
-  validate :validate_min_columns
-  validate :validate_max_columns
+  validate :validate_field_numbers_count
+  validate :validate_max_columns_count_if_no_headers
 
   def initialize(bulk_upload:, path:)
     @bulk_upload = bulk_upload
@@ -129,20 +129,16 @@ private
     end
   end
 
-  def validate_min_columns
+  def validate_field_numbers_count
     return if halt_validations?
 
-    column_count = rows.map(&:size).min
-
-    errors.add(:base, :under_min_column_count) if column_count < csv_parser.class::MIN_COLUMNS
+    errors.add(:base, :wrong_field_numbers_count) if csv_parser.incorrect_field_count?
   end
 
-  def validate_max_columns
+  def validate_max_columns_count_if_no_headers
     return if halt_validations?
 
-    column_count = rows.map(&:size).max
-
-    errors.add(:base, :over_max_column_count) if column_count > csv_parser.class::MAX_COLUMNS
+    errors.add(:base, :over_max_column_count) if csv_parser.too_many_columns?
   end
 
   def halt_validations!
diff --git a/app/services/bulk_upload/lettings/year2022/csv_parser.rb b/app/services/bulk_upload/lettings/year2022/csv_parser.rb
index c0d8d8900..3e6aaa640 100644
--- a/app/services/bulk_upload/lettings/year2022/csv_parser.rb
+++ b/app/services/bulk_upload/lettings/year2022/csv_parser.rb
@@ -1,8 +1,8 @@
 require "csv"
 
 class BulkUpload::Lettings::Year2022::CsvParser
-  MIN_COLUMNS = 134
-  MAX_COLUMNS = 136
+  FIELDS = 134
+  MAX_COLUMNS = 135
 
   attr_reader :path
 
@@ -11,7 +11,11 @@ class BulkUpload::Lettings::Year2022::CsvParser
   end
 
   def row_offset
-    with_headers? ? 5 : 0
+    if with_headers?
+      rows.find_index { |row| row[0].match(/field number/i) } + 1
+    else
+      0
+    end
   end
 
   def col_offset
@@ -25,8 +29,7 @@ class BulkUpload::Lettings::Year2022::CsvParser
   def row_parsers
     @row_parsers ||= body_rows.map do |row|
       stripped_row = row[col_offset..]
-      headers = ("field_1".."field_134").to_a
-      hash = Hash[headers.zip(stripped_row)]
+      hash = Hash[field_numbers.zip(stripped_row)]
 
       BulkUpload::Lettings::Year2022::RowParser.new(hash)
     end
@@ -41,17 +44,39 @@ class BulkUpload::Lettings::Year2022::CsvParser
   end
 
   def column_for_field(field)
-    cols[headers.find_index(field) + col_offset]
+    cols[field_numbers.find_index(field) + col_offset]
+  end
+
+  def incorrect_field_count?
+    valid_field_numbers_count = field_numbers.count { |f| f != "field_blank" }
+
+    valid_field_numbers_count != FIELDS
+  end
+
+  def too_many_columns?
+    return if with_headers?
+
+    max_columns_count = body_rows.map(&:size).max - col_offset
+
+    max_columns_count > MAX_COLUMNS
   end
 
 private
 
-  def headers
-    @headers ||= ("field_1".."field_134").to_a
+  def default_field_numbers
+    ("field_1".."field_#{FIELDS}").to_a
+  end
+
+  def field_numbers
+    @field_numbers ||= if with_headers?
+                         rows[row_offset - 1][col_offset..].map { |h| h.present? && h.match?(/^[0-9]+$/) ? "field_#{h}" : "field_blank" }
+                       else
+                         default_field_numbers
+                       end
   end
 
   def with_headers?
-    rows[0][0]&.match?(/\D+/)
+    rows.map { |r| r[0] }.any? { |cell| cell&.match?(/field number/i) }
   end
 
   def row_sep
diff --git a/app/services/bulk_upload/lettings/year2022/row_parser.rb b/app/services/bulk_upload/lettings/year2022/row_parser.rb
index 5b88ebdbe..b6ba93dc5 100644
--- a/app/services/bulk_upload/lettings/year2022/row_parser.rb
+++ b/app/services/bulk_upload/lettings/year2022/row_parser.rb
@@ -142,6 +142,8 @@ class BulkUpload::Lettings::Year2022::RowParser
   attribute :bulk_upload
   attribute :block_log_creation, :boolean, default: -> { false }
 
+  attribute :field_blank
+
   attribute :field_1, :integer
   attribute :field_2
   attribute :field_3
@@ -366,7 +368,7 @@ class BulkUpload::Lettings::Year2022::RowParser
   def blank_row?
     attribute_set
       .to_hash
-      .reject { |k, _| %w[bulk_upload block_log_creation].include?(k) }
+      .reject { |k, _| %w[bulk_upload block_log_creation field_blank].include?(k) }
       .values
       .reject(&:blank?)
       .compact
diff --git a/app/services/bulk_upload/lettings/year2023/csv_parser.rb b/app/services/bulk_upload/lettings/year2023/csv_parser.rb
index 6f661922c..cc351d603 100644
--- a/app/services/bulk_upload/lettings/year2023/csv_parser.rb
+++ b/app/services/bulk_upload/lettings/year2023/csv_parser.rb
@@ -1,8 +1,8 @@
 require "csv"
 
 class BulkUpload::Lettings::Year2023::CsvParser
-  MIN_COLUMNS = 141
-  MAX_COLUMNS = 143
+  FIELDS = 134
+  MAX_COLUMNS = 142
 
   attr_reader :path
 
@@ -47,15 +47,29 @@ class BulkUpload::Lettings::Year2023::CsvParser
     cols[field_numbers.find_index(field) + col_offset]
   end
 
+  def incorrect_field_count?
+    valid_field_numbers_count = field_numbers.count { |f| f != "field_blank" }
+
+    valid_field_numbers_count != FIELDS
+  end
+
+  def too_many_columns?
+    return if with_headers?
+
+    max_columns_count = body_rows.map(&:size).max - col_offset
+
+    max_columns_count > MAX_COLUMNS
+  end
+
 private
 
   def default_field_numbers
-    [5, nil, nil, 15, 16, nil, 13, 40, 41, 42, 43, 46, 52, 56, 60, 64, 68, 72, 76, 47, 53, 57, 61, 65, 69, 73, 77, 51, 55, 59, 63, 67, 71, 75, 50, 54, 58, 62, 66, 70, 74, 78, 48, 49, 79, 81, 82, 123, 124, 122, 120, 102, 103, nil, 83, 84, 85, 86, 87, 88, 104, 109, 107, 108, 106, 100, 101, 105, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 126, 128, 129, 130, 131, 132, 127, 125, 133, 134, 33, 34, 35, 36, 37, 38, nil, 7, 8, 9, 28, 14, 32, 29, 30, 31, 26, 27, 25, 23, 24, nil, 1, 3, 2, 80, nil, 121, 44, 89, 98, 92, 95, 90, 91, 93, 94, 97, 96, 99, 10, 11, 12, 45, 39, 6, 4, 17, 18, 19, 20, 21, 22].map { |h| h.present? ? "field_#{h}" : "field_blank" }
+    [5, nil, nil, 15, 16, nil, 13, 40, 41, 42, 43, 46, 52, 56, 60, 64, 68, 72, 76, 47, 53, 57, 61, 65, 69, 73, 77, 51, 55, 59, 63, 67, 71, 75, 50, 54, 58, 62, 66, 70, 74, 78, 48, 49, 79, 81, 82, 123, 124, 122, 120, 102, 103, nil, 83, 84, 85, 86, 87, 88, 104, 109, 107, 108, 106, 100, 101, 105, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 126, 128, 129, 130, 131, 132, 127, 125, 133, 134, 33, 34, 35, 36, 37, 38, nil, 7, 8, 9, 28, 14, 32, 29, 30, 31, 26, 27, 25, 23, 24, nil, 1, 3, 2, 80, nil, 121, 44, 89, 98, 92, 95, 90, 91, 93, 94, 97, 96, 99, 10, 11, 12, 45, 39, 6, 4, 17, 18, 19, 20, 21, 22].map { |h| h.present? && h.to_s.match?(/^[0-9]+$/) ? "field_#{h}" : "field_blank" }
   end
 
   def field_numbers
     @field_numbers ||= if with_headers?
-                         rows[row_offset - 1][col_offset..].map { |h| h.present? ? "field_#{h}" : "field_blank" }
+                         rows[row_offset - 1][col_offset..].map { |h| h.present? && h.match?(/^[0-9]+$/) ? "field_#{h}" : "field_blank" }
                        else
                          default_field_numbers
                        end
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 12738ad93..7bf8839a9 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -44,8 +44,8 @@ en:
         bulk_upload/lettings/validator:
           attributes:
             base:
+              wrong_field_numbers_count: "incorrect number of fields, please ensure you have used the correct template"
               over_max_column_count: "too many columns, please ensure you have used the correct template"
-              under_min_column_count: "too few columns, please ensure you have used the correct template"
         forms/bulk_upload_lettings/year:
           attributes:
             year:
diff --git a/spec/services/bulk_upload/lettings/validator_spec.rb b/spec/services/bulk_upload/lettings/validator_spec.rb
index 5eeb32c4a..679602ec0 100644
--- a/spec/services/bulk_upload/lettings/validator_spec.rb
+++ b/spec/services/bulk_upload/lettings/validator_spec.rb
@@ -5,6 +5,7 @@ RSpec.describe BulkUpload::Lettings::Validator do
 
   let(:organisation) { create(:organisation, old_visible_id: "3") }
   let(:user) { create(:user, organisation:) }
+  let(:log) { build(:lettings_log, :completed) }
   let(:bulk_upload) { create(:bulk_upload, user:) }
   let(:path) { file.path }
   let(:file) { Tempfile.new }
@@ -16,31 +17,181 @@ RSpec.describe BulkUpload::Lettings::Validator do
       end
     end
 
-    context "when file has too many columns" do
-      before do
-        file.write("a," * 136)
-        file.write("\n")
-        file.rewind
+    context "when 2022" do
+      let(:bulk_upload) { create(:bulk_upload, user:, year: 2022) }
+
+      context "when file has no headers" do
+        context "and too many columns" do
+          before do
+            file.write(("a" * 136).chars.join(","))
+            file.write("\n")
+            file.rewind
+          end
+
+          it "is not valid" do
+            expect(validator).not_to be_valid
+            expect(validator.errors["base"]).to eql(["too many columns, please ensure you have used the correct template"])
+          end
+        end
+
+        context "and doesn't have too many columns" do
+          before do
+            file.write(("a" * 135).chars.join(","))
+            file.write("\n")
+            file.rewind
+          end
+
+          it "is valid" do
+            expect(validator).to be_valid
+          end
+        end
       end
 
-      it "is not valid" do
-        expect(validator).not_to be_valid
+      context "when file has headers" do
+        context "and file has extra invalid headers" do
+          let(:seed) { rand }
+          let(:log_to_csv) { BulkUpload::LogToCsv.new(log:) }
+          let(:field_numbers) { log_to_csv.default_2022_field_numbers + %w[invalid_field_number] }
+          let(:field_values) { log_to_csv.to_2022_row + %w[value_for_invalid_field_number] }
+
+          before do
+            file.write(log_to_csv.custom_field_numbers_row(seed:, field_numbers:))
+            file.write(log_to_csv.to_custom_csv_row(seed:, field_values:))
+            file.rewind
+          end
+
+          it "is valid" do
+            expect(validator).to be_valid
+          end
+        end
+
+        context "and file has too few valid headers" do
+          let(:seed) { rand }
+          let(:log_to_csv) { BulkUpload::LogToCsv.new(log:) }
+          let(:field_numbers) { log_to_csv.default_2022_field_numbers }
+          let(:field_values) { log_to_csv.to_2022_row }
+
+          before do
+            field_numbers.delete_at(20)
+            field_values.delete_at(20)
+            file.write(log_to_csv.custom_field_numbers_row(seed:, field_numbers:))
+            file.write(log_to_csv.to_custom_csv_row(seed:, field_values:))
+            file.rewind
+          end
+
+          it "is not valid" do
+            expect(validator).not_to be_valid
+            expect(validator.errors["base"]).to eql(["incorrect number of fields, please ensure you have used the correct template"])
+          end
+        end
+
+        context "and file has too many valid headers" do
+          let(:seed) { rand }
+          let(:log_to_csv) { BulkUpload::LogToCsv.new(log:) }
+          let(:field_numbers) { log_to_csv.default_2022_field_numbers + %w[23] }
+          let(:field_values) { log_to_csv.to_2022_row + %w[value] }
+
+          before do
+            file.write(log_to_csv.custom_field_numbers_row(seed:, field_numbers:))
+            file.write(log_to_csv.to_custom_csv_row(seed:, field_values:))
+            file.rewind
+          end
+
+          it "is not valid" do
+            expect(validator).not_to be_valid
+            expect(validator.errors["base"]).to eql(["incorrect number of fields, please ensure you have used the correct template"])
+          end
+        end
       end
     end
 
-    context "when file has too few columns" do
-      before do
-        file.write("a," * 132)
-        file.write("\n")
-        file.rewind
+    context "when 2023" do
+      let(:bulk_upload) { create(:bulk_upload, user:, year: 2023) }
+
+      context "when file has no headers" do
+        context "and too many columns" do
+          before do
+            file.write(("a" * 143).chars.join(","))
+            file.write("\n")
+            file.rewind
+          end
+
+          it "is not valid" do
+            expect(validator).not_to be_valid
+            expect(validator.errors["base"]).to eql(["too many columns, please ensure you have used the correct template"])
+          end
+        end
+
+        context "and doesn't have too many columns" do
+          before do
+            file.write(("a" * 142).chars.join(","))
+            file.write("\n")
+            file.rewind
+          end
+
+          it "is valid" do
+            expect(validator).to be_valid
+          end
+        end
       end
 
-      it "is not valid" do
-        expect(validator).not_to be_valid
+      context "when file has headers" do
+        context "and file has extra invalid headers" do
+          let(:seed) { rand }
+          let(:log_to_csv) { BulkUpload::LogToCsv.new(log:) }
+          let(:field_numbers) { log_to_csv.default_2023_field_numbers + %w[invalid_field_number] }
+          let(:field_values) { log_to_csv.to_2023_row + %w[value_for_invalid_field_number] }
+
+          before do
+            file.write(log_to_csv.custom_field_numbers_row(seed:, field_numbers:))
+            file.write(log_to_csv.to_custom_csv_row(seed:, field_values:))
+            file.rewind
+          end
+
+          it "is valid" do
+            expect(validator).to be_valid
+          end
+        end
+
+        context "and file has too few valid headers" do
+          let(:seed) { rand }
+          let(:log_to_csv) { BulkUpload::LogToCsv.new(log:) }
+          let(:field_numbers) { log_to_csv.default_2023_field_numbers }
+          let(:field_values) { log_to_csv.to_2023_row }
+
+          before do
+            field_numbers.delete_at(20)
+            field_values.delete_at(20)
+            file.write(log_to_csv.custom_field_numbers_row(seed:, field_numbers:))
+            file.write(log_to_csv.to_custom_csv_row(seed:, field_values:))
+            file.rewind
+          end
+
+          it "is not valid" do
+            expect(validator).not_to be_valid
+            expect(validator.errors["base"]).to eql(["incorrect number of fields, please ensure you have used the correct template"])
+          end
+        end
+
+        context "and file has too many valid headers" do
+          let(:seed) { rand }
+          let(:log_to_csv) { BulkUpload::LogToCsv.new(log:) }
+          let(:field_numbers) { log_to_csv.default_2023_field_numbers + %w[23] }
+          let(:field_values) { log_to_csv.to_2023_row + %w[value] }
+
+          before do
+            file.write(log_to_csv.custom_field_numbers_row(seed:, field_numbers:))
+            file.write(log_to_csv.to_custom_csv_row(seed:, field_values:))
+            file.rewind
+          end
+
+          it "is not valid" do
+            expect(validator).not_to be_valid
+            expect(validator.errors["base"]).to eql(["incorrect number of fields, please ensure you have used the correct template"])
+          end
+        end
       end
     end
-
-    context "when incorrect headers"
   end
 
   describe "#call" do
diff --git a/spec/services/bulk_upload/lettings/year2022/csv_parser_spec.rb b/spec/services/bulk_upload/lettings/year2022/csv_parser_spec.rb
index d396ad78e..10e722e9a 100644
--- a/spec/services/bulk_upload/lettings/year2022/csv_parser_spec.rb
+++ b/spec/services/bulk_upload/lettings/year2022/csv_parser_spec.rb
@@ -3,24 +3,86 @@ require "rails_helper"
 RSpec.describe BulkUpload::Lettings::Year2022::CsvParser do
   subject(:service) { described_class.new(path:) }
 
-  let(:path) { file_fixture("2022_23_lettings_bulk_upload.csv") }
+  let(:file) { Tempfile.new }
+  let(:path) { file.path }
+  let(:log) { build(:lettings_log, :completed) }
 
   context "when parsing csv with headers" do
+    before do
+      file.write(BulkUpload::LogToCsv.new(log:).default_2022_field_numbers_row)
+      file.write(BulkUpload::LogToCsv.new(log:).to_2022_csv_row)
+      file.rewind
+    end
+
     it "returns correct offsets" do
-      expect(service.row_offset).to eq(5)
+      expect(service.row_offset).to eq(1)
       expect(service.col_offset).to eq(1)
     end
 
     it "parses csv correctly" do
-      expect(service.row_parsers[0].field_12.to_i).to eq(55)
+      expect(service.row_parsers[0].field_12.to_i).to eq(35)
     end
   end
 
-  context "when parsing csv without headers" do
-    let(:file) { Tempfile.new }
-    let(:path) { file.path }
-    let(:log) { build(:lettings_log, :completed) }
+  context "when parsing csv with headers with extra rows" do
+    before do
+      file.write("Extra row\n")
+      file.write(BulkUpload::LogToCsv.new(log:).default_2022_field_numbers_row)
+      file.write(BulkUpload::LogToCsv.new(log:).to_2022_csv_row)
+      file.rewind
+    end
+
+    it "returns correct offsets" do
+      expect(service.row_offset).to eq(2)
+      expect(service.col_offset).to eq(1)
+    end
+
+    it "parses csv correctly" do
+      expect(service.row_parsers[0].field_12.to_i).to eq(35)
+    end
+  end
+
+  context "when parsing csv with headers in arbitrary order" do
+    let(:seed) { rand }
 
+    before do
+      file.write(BulkUpload::LogToCsv.new(log:).default_2022_field_numbers_row(seed:))
+      file.write(BulkUpload::LogToCsv.new(log:).to_2022_csv_row(seed:))
+      file.rewind
+    end
+
+    it "returns correct offsets" do
+      expect(service.row_offset).to eq(1)
+      expect(service.col_offset).to eq(1)
+    end
+
+    it "parses csv correctly" do
+      expect(service.row_parsers[0].field_12.to_i).to eq(35)
+    end
+  end
+
+  context "when parsing csv with extra invalid headers" do
+    let(:seed) { rand }
+    let(:log_to_csv) { BulkUpload::LogToCsv.new(log:) }
+    let(:field_numbers) { log_to_csv.default_2022_field_numbers + %w[invalid_field_number] }
+    let(:field_values) { log_to_csv.to_2022_row + %w[value_for_invalid_field_number] }
+
+    before do
+      file.write(log_to_csv.custom_field_numbers_row(seed:, field_numbers:))
+      file.write(log_to_csv.to_custom_csv_row(seed:, field_values:))
+      file.rewind
+    end
+
+    it "parses csv correctly" do
+      expect(service.row_parsers[0].field_12.to_i).to eq(35)
+    end
+
+    it "counts the number of valid field numbers correctly" do
+      expect(service.incorrect_field_count?).to be false
+    end
+  end
+
+  context "when parsing csv without headers" do
     before do
       file.write(BulkUpload::LogToCsv.new(log:, col_offset: 0).to_2022_csv_row)
       file.rewind
@@ -32,59 +94,55 @@ RSpec.describe BulkUpload::Lettings::Year2022::CsvParser do
     end
 
     it "parses csv correctly" do
-      expect(service.row_parsers[0].field_12.to_i).to eql(log.age1)
+      expect(service.row_parsers[0].field_12.to_i).to be(35)
     end
   end
 
   context "when parsing with BOM aka byte order mark" do
-    let(:file) { Tempfile.new }
-    let(:path) { file.path }
-    let(:log) { build(:lettings_log, :completed) }
     let(:bom) { "\uFEFF" }
 
     before do
       file.write(bom)
       file.write(BulkUpload::LogToCsv.new(log:, col_offset: 0).to_2022_csv_row)
-      file.close
+      file.rewind
     end
 
     it "parses csv correctly" do
-      expect(service.row_parsers[0].field_12.to_i).to eql(log.age1)
+      expect(service.row_parsers[0].field_12.to_i).to be(35)
     end
   end
 
   context "when an invalid byte sequence" do
-    let(:file) { Tempfile.new }
-    let(:path) { file.path }
-    let(:log) { build(:lettings_log, :completed) }
     let(:invalid_sequence) { "\x81" }
 
     before do
       file.write(invalid_sequence)
       file.write(BulkUpload::LogToCsv.new(log:, col_offset: 0).to_2022_csv_row)
-      file.close
+      file.rewind
     end
 
     it "parses csv correctly" do
-      expect(service.row_parsers[0].field_12.to_i).to eql(log.age1)
+      expect(service.row_parsers[0].field_12.to_i).to be(35)
     end
   end
 
   describe "#column_for_field", aggregate_failures: true do
-    context "when headers present" do
+    context "when with headers using default ordering" do
+      before do
+        file.write(BulkUpload::LogToCsv.new(log:).default_2022_field_numbers_row)
+        file.write(BulkUpload::LogToCsv.new(log:).to_2022_csv_row)
+        file.rewind
+      end
+
       it "returns correct column" do
         expect(service.column_for_field("field_1")).to eql("B")
         expect(service.column_for_field("field_134")).to eql("EE")
       end
     end
 
-    context "when no headers" do
-      let(:file) { Tempfile.new }
-      let(:path) { file.path }
-      let(:log) { build(:lettings_log, :completed) }
-
+    context "when without headers using default ordering" do
       before do
-        file.write(BulkUpload::LogToCsv.new(log:, col_offset: 0).to_2022_csv_row)
+        file.write(BulkUpload::LogToCsv.new(log:).to_2022_csv_row)
         file.rewind
       end
 
@@ -93,5 +151,22 @@ RSpec.describe BulkUpload::Lettings::Year2022::CsvParser do
         expect(service.column_for_field("field_134")).to eql("ED")
       end
     end
+
+    context "when with headers using custom ordering" do
+      let(:seed) { 123 }
+
+      before do
+        file.write(BulkUpload::LogToCsv.new(log:).default_2022_field_numbers_row(seed:))
+        file.write(BulkUpload::LogToCsv.new(log:).to_2022_csv_row(seed:))
+        file.rewind
+      end
+
+      it "returns correct column" do
+        expect(service.column_for_field("field_1")).to eql("I")
+        expect(service.column_for_field("field_45")).to eql("BE")
+        expect(service.column_for_field("field_90")).to eql("AN")
+        expect(service.column_for_field("field_134")).to eql("BA")
+      end
+    end
   end
 end
diff --git a/spec/services/bulk_upload/lettings/year2023/csv_parser_spec.rb b/spec/services/bulk_upload/lettings/year2023/csv_parser_spec.rb
index a8cf227f4..fc82faa8d 100644
--- a/spec/services/bulk_upload/lettings/year2023/csv_parser_spec.rb
+++ b/spec/services/bulk_upload/lettings/year2023/csv_parser_spec.rb
@@ -79,6 +79,33 @@ RSpec.describe BulkUpload::Lettings::Year2023::CsvParser do
     end
   end
 
+  context "when parsing csv with extra invalid headers" do
+    let(:seed) { rand }
+    let(:log_to_csv) { BulkUpload::LogToCsv.new(log:) }
+    let(:field_numbers) { log_to_csv.default_2023_field_numbers + %w[invalid_field_number] }
+    let(:field_values) { log_to_csv.to_2023_row + %w[value_for_invalid_field_number] }
+
+    before do
+      file.write("Question\n")
+      file.write("Additional info\n")
+      file.write("Values\n")
+      file.write("Can be empty?\n")
+      file.write("Type of letting the question applies to\n")
+      file.write("Duplicate check field?\n")
+      file.write(log_to_csv.custom_field_numbers_row(seed:, field_numbers:))
+      file.write(log_to_csv.to_custom_csv_row(seed:, field_values:))
+      file.rewind
+    end
+
+    it "parses csv correctly" do
+      expect(service.row_parsers[0].field_13).to eql(log.tenancycode)
+    end
+
+    it "counts the number of valid field numbers correctly" do
+      expect(service.incorrect_field_count?).to be false
+    end
+  end
+
   context "when parsing csv without headers" do
     before do
       file.write(BulkUpload::LogToCsv.new(log:, col_offset: 0).to_2023_csv_row)
diff --git a/spec/support/bulk_upload/log_to_csv.rb b/spec/support/bulk_upload/log_to_csv.rb
index d5c64a6ee..6064e57e3 100644
--- a/spec/support/bulk_upload/log_to_csv.rb
+++ b/spec/support/bulk_upload/log_to_csv.rb
@@ -12,14 +12,31 @@ class BulkUpload::LogToCsv
     [nil] * col_offset
   end
 
-  def to_2022_csv_row
-    (row_prefix + to_2022_row).flatten.join(",") + line_ending
+  def to_2022_csv_row(seed: nil)
+    if seed
+      row = to_2022_row.shuffle(random: Random.new(seed))
+      (row_prefix + row).flatten.join(",") + line_ending
+    else
+      (row_prefix + to_2022_row).flatten.join(",") + line_ending
+    end
   end
 
   def to_2022_sales_csv_row
     (row_prefix + to_2022_sales_row).flatten.join(",") + line_ending
   end
 
+  def default_2022_field_numbers
+    (1..134).to_a
+  end
+
+  def default_2022_field_numbers_row(seed: nil)
+    if seed
+      ["Bulk upload field number"] + default_2022_field_numbers.shuffle(random: Random.new(seed))
+    else
+      ["Bulk upload field number"] + default_2022_field_numbers
+    end.flatten.join(",") + line_ending
+  end
+
   def to_2023_csv_row(seed: nil)
     if seed
       row = to_2023_row.shuffle(random: Random.new(seed))
@@ -202,6 +219,21 @@ class BulkUpload::LogToCsv
     ]
   end
 
+  def custom_field_numbers_row(seed: nil, field_numbers: nil)
+    if seed
+      ["Bulk upload field number"] + field_numbers.shuffle(random: Random.new(seed))
+    else
+      ["Bulk upload field number"] + field_numbers
+    end.flatten.join(",") + line_ending
+  end
+
+  def to_custom_csv_row(seed: nil, field_values: nil)
+    if seed
+      row = field_values.shuffle(random: Random.new(seed))
+    end
+    (row_prefix + row).flatten.join(",") + line_ending
+  end
+
   def to_2022_sales_row
     [
       log.purchid, # 1