diff --git a/app/models/derived_variables/sales_log_variables.rb b/app/models/derived_variables/sales_log_variables.rb
index a31cfab61..2a41b7909 100644
--- a/app/models/derived_variables/sales_log_variables.rb
+++ b/app/models/derived_variables/sales_log_variables.rb
@@ -98,6 +98,8 @@ module DerivedVariables::SalesLogVariables
     self.numstair = is_firststair? ? 1 : nil if numstair == 1 && firststair_changed?
     self.mrent = 0 if stairowned_100?
 
+    clear_gender_description_unless_gender_not_same_as_sex! if form.start_year_2026_or_later?
+
     set_encoded_derived_values!(DEPENDENCIES)
   end
 
@@ -254,6 +256,18 @@ private
     [1, 2].include?(prevten) || [1, 2].include?(prevtenbuy2)
   end
 
+  def clear_gender_description_unless_gender_not_same_as_sex!
+    # we do this as the gender same as sex page always contains the gender description box that's hidden
+    # default submit will send a "" for gender description. this ensure it's nil in this case
+    # as well as blanking it if the user writes it in mistakenly in bulk upload
+    (1..6).each do |person_index|
+      gender_same_as_sex = public_send("gender_same_as_sex#{person_index}")
+      if gender_same_as_sex.present? && gender_same_as_sex != 2
+        self["gender_description#{person_index}"] = nil
+      end
+    end
+  end
+
   def reset_address_fields!
     self.uprn = nil
     self.uprn_known = nil
diff --git a/app/services/bulk_upload/sales/year2026/row_parser.rb b/app/services/bulk_upload/sales/year2026/row_parser.rb
index adb7cc6a2..cf7b0aff0 100644
--- a/app/services/bulk_upload/sales/year2026/row_parser.rb
+++ b/app/services/bulk_upload/sales/year2026/row_parser.rb
@@ -142,6 +142,19 @@ class BulkUpload::Sales::Year2026::RowParser
     field_125: "Person 4's sex, as registered at birth",
     field_126: "Person 5's sex, as registered at birth",
     field_127: "Person 6's sex, as registered at birth",
+
+    field_128: "Is the gender buyer 1 identifies with the same as their sex registered at birth?",
+    field_129: "If 'No', enter buyer 1's gender identity",
+    field_130: "Is the gender buyer/person 2 identifies with the same as their sex registered at birth?",
+    field_131: "If 'No', enter buyer/person 2's gender identity",
+    field_132: "Is the gender person 3 identifies with the same as their sex registered at birth?",
+    field_133: "If 'No', enter person 3's gender identity",
+    field_134: "Is the gender person 4 identifies with the same as their sex registered at birth?",
+    field_135: "If 'No', enter person 4's gender identity",
+    field_136: "Is the gender person 5 identifies with the same as their sex registered at birth?",
+    field_137: "If 'No', enter person 5's gender identity",
+    field_138: "Is the gender person 6 identifies with the same as their sex registered at birth?",
+    field_139: "If 'No', enter person 6's gender identity",
   }.freeze
 
   ERROR_BASE_KEY = "validations.sales.2026.bulk_upload".freeze
@@ -289,6 +302,19 @@ class BulkUpload::Sales::Year2026::RowParser
   attribute :field_126, :string
   attribute :field_127, :string
 
+  attribute :field_128, :integer
+  attribute :field_129, :string
+  attribute :field_130, :integer
+  attribute :field_131, :string
+  attribute :field_132, :integer
+  attribute :field_133, :string
+  attribute :field_134, :integer
+  attribute :field_135, :string
+  attribute :field_136, :integer
+  attribute :field_137, :string
+  attribute :field_138, :integer
+  attribute :field_139, :string
+
   validates :field_1,
             presence: {
               message: I18n.t("#{ERROR_BASE_KEY}.not_answered", question: "sale completion date (day)."),
@@ -801,6 +827,19 @@ private
       sexrab4: %i[field_125],
       sexrab5: %i[field_126],
       sexrab6: %i[field_127],
+
+      gender_same_as_sex1: %i[field_128],
+      gender_description1: %i[field_129],
+      gender_same_as_sex2: %i[field_130],
+      gender_description2: %i[field_131],
+      gender_same_as_sex3: %i[field_132],
+      gender_description3: %i[field_133],
+      gender_same_as_sex4: %i[field_134],
+      gender_description4: %i[field_135],
+      gender_same_as_sex5: %i[field_136],
+      gender_description5: %i[field_137],
+      gender_same_as_sex6: %i[field_138],
+      gender_description6: %i[field_139],
     }
   end
 
@@ -843,6 +882,19 @@ private
     attributes["sexrab5"] = field_126
     attributes["sexrab6"] = field_127
 
+    attributes["gender_same_as_sex1"] = field_128
+    attributes["gender_description1"] = field_129
+    attributes["gender_same_as_sex2"] = field_130
+    attributes["gender_description2"] = field_131
+    attributes["gender_same_as_sex3"] = field_132
+    attributes["gender_description3"] = field_133
+    attributes["gender_same_as_sex4"] = field_134
+    attributes["gender_description4"] = field_135
+    attributes["gender_same_as_sex5"] = field_136
+    attributes["gender_description5"] = field_137
+    attributes["gender_same_as_sex6"] = field_138
+    attributes["gender_description6"] = field_139
+
     attributes["relat2"] = relationship_from_is_partner(field_34)
     attributes["relat3"] = relationship_from_is_partner(field_42)
     attributes["relat4"] = relationship_from_is_partner(field_46)
diff --git a/app/services/csv/sales_log_csv_service.rb b/app/services/csv/sales_log_csv_service.rb
index ed16653f1..f83a90674 100644
--- a/app/services/csv/sales_log_csv_service.rb
+++ b/app/services/csv/sales_log_csv_service.rb
@@ -115,6 +115,7 @@ module Csv
       (2..6).each do |i|
         hash["age#{i}"] = { "refused_code" => "-9", "refused_label" => "Not known", "details_known_field" => "details_known_#{i}", "age_known_field" => "age#{i}_known" }
         hash["sexrab#{i}"] = { "refused_code" => "R", "refused_label" => "Prefers not to say", "details_known_field" => "details_known_#{i}" }
+        hash["gender_same_as_sex#{i}"] = { "refused_code" => "3", "refused_label" => "Prefers not to say", "details_known_field" => "details_known_#{i}" }
         hash["sex#{i}"] = { "refused_code" => "R", "refused_label" => "Prefers not to say", "details_known_field" => "details_known_#{i}" }
         hash["relat#{i}"] = { "refused_code" => "R", "refused_label" => "Prefers not to say", "details_known_field" => "details_known_#{i}" }
         hash["ecstat#{i}"] = { "refused_code" => "10", "refused_label" => "Prefers not to say", "details_known_field" => "details_known_#{i}" }
diff --git a/app/services/exports/sales_log_export_constants.rb b/app/services/exports/sales_log_export_constants.rb
index 6dfb2b334..806d7862f 100644
--- a/app/services/exports/sales_log_export_constants.rb
+++ b/app/services/exports/sales_log_export_constants.rb
@@ -150,5 +150,7 @@ module Exports::SalesLogExportConstants
 
   (1..6).each do |index|
     YEAR_2026_EXPORT_FIELDS << "SEXRAB#{index}"
+    YEAR_2026_EXPORT_FIELDS << "GENDER_SAME_AS_SEX#{index}"
+    YEAR_2026_EXPORT_FIELDS << "GENDER_DESCRIPTION#{index}"
   end
 end