diff --git a/app/models/location.rb b/app/models/location.rb
index 19cf5e211..03af24a94 100644
--- a/app/models/location.rb
+++ b/app/models/location.rb
@@ -121,6 +121,30 @@ class Location < ApplicationRecord
 
   scope :visible, -> { where(discarded_at: nil) }
 
+  scope :duplicate_sets, lambda {
+    scope = visible
+    .group(*DUPLICATE_LOCATION_ATTRIBUTES)
+    .where.not(scheme_id: nil)
+    .where.not(postcode: nil)
+    .where.not(mobility_type: nil)
+    .having(
+      "COUNT(*) > 1",
+    )
+    scope.pluck("ARRAY_AGG(id)")
+  }
+
+  scope :duplicate_sets_within_given_schemes, lambda {
+    scope = visible
+    .group(*DUPLICATE_LOCATION_ATTRIBUTES - %w[scheme_id])
+    .where.not(postcode: nil)
+    .where.not(mobility_type: nil)
+    .having(
+      "COUNT(*) > 1",
+    )
+    scope.pluck("ARRAY_AGG(id)")
+  }
+
+  DUPLICATE_LOCATION_ATTRIBUTES = %w[scheme_id postcode mobility_type].freeze
   LOCAL_AUTHORITIES = LocalAuthority.all.map { |la| [la.name, la.code] }.to_h
 
   enum local_authorities: LOCAL_AUTHORITIES
diff --git a/app/models/scheme.rb b/app/models/scheme.rb
index 6d3524723..2c73acc06 100644
--- a/app/models/scheme.rb
+++ b/app/models/scheme.rb
@@ -103,6 +103,22 @@ class Scheme < ApplicationRecord
 
   scope :visible, -> { where(discarded_at: nil) }
 
+  scope :duplicate_sets, lambda {
+    scope = visible
+    .group(*DUPLICATE_SCHEME_ATTRIBUTES)
+    .where.not(scheme_type: nil)
+    .where.not(registered_under_care_act: nil)
+    .where.not(primary_client_group: nil)
+    .where.not(has_other_client_group: nil)
+    .where.not(secondary_client_group: nil).or(where(has_other_client_group: 0))
+    .where.not(support_type: nil)
+    .where.not(intended_stay: nil)
+    .having(
+      "COUNT(*) > 1",
+    )
+    scope.pluck("ARRAY_AGG(id)")
+  }
+
   validate :validate_confirmed
   validate :validate_owning_organisation
 
@@ -192,6 +208,8 @@ class Scheme < ApplicationRecord
     "Missing": "X",
   }.freeze
 
+  DUPLICATE_SCHEME_ATTRIBUTES = %w[scheme_type registered_under_care_act primary_client_group secondary_client_group has_other_client_group support_type intended_stay].freeze
+
   enum arrangement_type: ARRANGEMENT_TYPE, _suffix: true
 
   def self.find_by_id_on_multiple_fields(scheme_id, location_id)
diff --git a/lib/tasks/count_duplicates.rake b/lib/tasks/count_duplicates.rake
new file mode 100644
index 000000000..e65688b4d
--- /dev/null
+++ b/lib/tasks/count_duplicates.rake
@@ -0,0 +1,63 @@
+namespace :count_duplicates do
+  desc "Count the number of duplicate schemes per organisation"
+  task scheme_duplicates_per_org: :environment do
+    duplicates_csv = CSV.generate(headers: true) do |csv|
+      csv << ["Organisation id", "Number of duplicate sets", "Total duplicate schemes"]
+
+      Organisation.visible.each do |organisation|
+        if organisation.owned_schemes.duplicate_sets.count.positive?
+          csv << [organisation.id, organisation.owned_schemes.duplicate_sets.count, organisation.owned_schemes.duplicate_sets.sum(&:size)]
+        end
+      end
+    end
+
+    filename = "scheme-duplicates-#{Time.zone.now}.csv"
+    storage_service = Storage::S3Service.new(Configuration::EnvConfigurationService.new, ENV["BULK_UPLOAD_BUCKET"])
+    storage_service.write_file(filename, "#{duplicates_csv}")
+
+    url = storage_service.get_presigned_url(filename, 72.hours.to_i)
+    Rails.logger.info("Download URL: #{url}")
+  end
+
+  desc "Count the number of duplicate locations per organisation"
+  task location_duplicates_per_org: :environment do
+    duplicates_csv = CSV.generate(headers: true) do |csv|
+      csv << ["Organisation id", "Duplicate sets within individual schemes", "Duplicate locations within individual schemes", "All duplicate sets", "All duplicates"]
+
+      Organisation.visible.each do |organisation|
+        duplicate_sets_within_individual_schemes = []
+
+        organisation.owned_schemes.each do |scheme|
+          duplicate_sets_within_individual_schemes += scheme.locations.duplicate_sets
+        end
+        duplicate_locations_within_individual_schemes = duplicate_sets_within_individual_schemes.flatten
+
+        duplicate_sets_within_duplicate_schemes = []
+        if organisation.owned_schemes.duplicate_sets.count.positive?
+          organisation.owned_schemes.duplicate_sets.each do |duplicate_set|
+            duplicate_sets_within_duplicate_schemes += Location.where(scheme_id: duplicate_set).duplicate_sets_within_given_schemes
+          end
+          duplicate_locations_within_duplicate_schemes_ids = duplicate_sets_within_duplicate_schemes.flatten
+
+          duplicate_sets_within_individual_schemes_without_intersecting_sets = duplicate_sets_within_individual_schemes.reject { |set| set.any? { |id| duplicate_sets_within_duplicate_schemes.any? { |duplicate_set| duplicate_set.include?(id) } } }
+          all_duplicate_sets_count = (duplicate_sets_within_individual_schemes_without_intersecting_sets + duplicate_sets_within_duplicate_schemes).count
+          all_duplicate_locations_count = (duplicate_locations_within_duplicate_schemes_ids + duplicate_locations_within_individual_schemes).uniq.count
+        else
+          all_duplicate_sets_count = duplicate_sets_within_individual_schemes.count
+          all_duplicate_locations_count = duplicate_locations_within_individual_schemes.count
+        end
+
+        if all_duplicate_locations_count.positive?
+          csv << [organisation.id, duplicate_sets_within_individual_schemes.count, duplicate_locations_within_individual_schemes.count, all_duplicate_sets_count, all_duplicate_locations_count]
+        end
+      end
+    end
+
+    filename = "location-duplicates-#{Time.zone.now}.csv"
+    storage_service = Storage::S3Service.new(Configuration::EnvConfigurationService.new, ENV["BULK_UPLOAD_BUCKET"])
+    storage_service.write_file(filename, "#{duplicates_csv}")
+
+    url = storage_service.get_presigned_url(filename, 72.hours.to_i)
+    Rails.logger.info("Download URL: #{url}")
+  end
+end
diff --git a/spec/factories/scheme.rb b/spec/factories/scheme.rb
index 7983bfa0a..5f4ad30bc 100644
--- a/spec/factories/scheme.rb
+++ b/spec/factories/scheme.rb
@@ -32,5 +32,14 @@ FactoryBot.define do
       confirmed { false }
       support_type { nil }
     end
+    trait :duplicate do
+      scheme_type { 4 }
+      registered_under_care_act { 1 }
+      primary_client_group { "O" }
+      secondary_client_group { "H" }
+      has_other_client_group { 1 }
+      support_type { 2 }
+      intended_stay { "M" }
+    end
   end
 end
diff --git a/spec/lib/tasks/count_duplicates_spec.rb b/spec/lib/tasks/count_duplicates_spec.rb
new file mode 100644
index 000000000..99da5b2fb
--- /dev/null
+++ b/spec/lib/tasks/count_duplicates_spec.rb
@@ -0,0 +1,111 @@
+require "rails_helper"
+require "rake"
+
+RSpec.describe "count_duplicates" do
+  before do
+    allow(Storage::S3Service).to receive(:new).and_return(storage_service)
+    allow(storage_service).to receive(:write_file)
+    allow(storage_service).to receive(:get_presigned_url).and_return(test_url)
+  end
+
+  describe "count_duplicates:scheme_duplicates_per_org", type: :task do
+    subject(:task) { Rake::Task["count_duplicates:scheme_duplicates_per_org"] }
+
+    let(:storage_service) { instance_double(Storage::S3Service) }
+    let(:test_url) { "test_url" }
+
+    before do
+      Rake.application.rake_require("tasks/count_duplicates")
+      Rake::Task.define_task(:environment)
+      task.reenable
+    end
+
+    context "when the rake task is run" do
+      context "and there are no duplicate schemes" do
+        before do
+          create(:organisation)
+        end
+
+        it "creates a csv with headers only" do
+          expect(storage_service).to receive(:write_file).with(/scheme-duplicates-.*\.csv/, "\uFEFFOrganisation id,Number of duplicate sets,Total duplicate schemes\n")
+          expect(Rails.logger).to receive(:info).with("Download URL: #{test_url}")
+          task.invoke
+        end
+      end
+
+      context "and there are duplicate schemes" do
+        let(:organisation) { create(:organisation) }
+        let(:organisation2) { create(:organisation) }
+
+        before do
+          create_list(:scheme, 2, :duplicate, owning_organisation: organisation)
+          create_list(:scheme, 3, :duplicate, primary_client_group: "I", owning_organisation: organisation)
+          create_list(:scheme, 5, :duplicate, owning_organisation: organisation2)
+        end
+
+        it "creates a csv with correct duplicate numbers" do
+          expect(storage_service).to receive(:write_file).with(/scheme-duplicates-.*\.csv/, "\uFEFFOrganisation id,Number of duplicate sets,Total duplicate schemes\n#{organisation.id},2,5\n#{organisation2.id},1,5\n")
+          expect(Rails.logger).to receive(:info).with("Download URL: #{test_url}")
+          task.invoke
+        end
+      end
+    end
+  end
+
+  describe "count_duplicates:location_duplicates_per_org", type: :task do
+    subject(:task) { Rake::Task["count_duplicates:location_duplicates_per_org"] }
+
+    let(:storage_service) { instance_double(Storage::S3Service) }
+    let(:test_url) { "test_url" }
+
+    before do
+      Rake.application.rake_require("tasks/count_duplicates")
+      Rake::Task.define_task(:environment)
+      task.reenable
+    end
+
+    context "when the rake task is run" do
+      context "and there are no duplicate locations" do
+        before do
+          create(:organisation)
+        end
+
+        it "creates a csv with headers only" do
+          expect(storage_service).to receive(:write_file).with(/location-duplicates-.*\.csv/, "\uFEFFOrganisation id,Duplicate sets within individual schemes,Duplicate locations within individual schemes,All duplicate sets,All duplicates\n")
+          expect(Rails.logger).to receive(:info).with("Download URL: #{test_url}")
+          task.invoke
+        end
+      end
+
+      context "and there are duplicate locations" do
+        let(:organisation) { create(:organisation) }
+        let(:scheme_a) { create(:scheme, :duplicate, owning_organisation: organisation) }
+        let(:scheme_b) { create(:scheme, :duplicate, owning_organisation: organisation) }
+        let(:scheme_c) { create(:scheme, owning_organisation: organisation) }
+        let(:organisation2) { create(:organisation) }
+        let(:scheme2) { create(:scheme, owning_organisation: organisation2) }
+        let(:scheme3) { create(:scheme, owning_organisation: organisation2) }
+
+        before do
+          create_list(:location, 2, postcode: "A1 1AB", mobility_type: "M", scheme: scheme_a) # Location A
+          create_list(:location, 1, postcode: "A1 1AB", mobility_type: "A", scheme: scheme_a) # Location B
+
+          create_list(:location, 1, postcode: "A1 1AB", mobility_type: "M", scheme: scheme_b) # Location A
+          create_list(:location, 1, postcode: "A1 1AB", mobility_type: "A", scheme: scheme_b) # Location B
+          create_list(:location, 2, postcode: "A1 1AB", mobility_type: "N", scheme: scheme_b) # Location C
+
+          create_list(:location, 2, postcode: "A1 1AB", mobility_type: "A", scheme: scheme_c) # Location B
+
+          create_list(:location, 5, postcode: "A1 1AB", mobility_type: "M", scheme: scheme2)
+          create_list(:location, 2, postcode: "A1 1AB", mobility_type: "M", scheme: scheme3)
+        end
+
+        it "creates a csv with correct duplicate numbers" do
+          expect(storage_service).to receive(:write_file).with(/location-duplicates-.*\.csv/, "\uFEFFOrganisation id,Duplicate sets within individual schemes,Duplicate locations within individual schemes,All duplicate sets,All duplicates\n#{organisation.id},3,6,4,9\n#{organisation2.id},2,7,2,7\n")
+          expect(Rails.logger).to receive(:info).with("Download URL: #{test_url}")
+          task.invoke
+        end
+      end
+    end
+  end
+end
diff --git a/spec/models/location_spec.rb b/spec/models/location_spec.rb
index 4856c5662..79265d361 100644
--- a/spec/models/location_spec.rb
+++ b/spec/models/location_spec.rb
@@ -831,6 +831,76 @@ RSpec.describe Location, type: :model do
         expect(described_class.active.count).to eq(2)
       end
     end
+
+    context "when getting list of duplicate locations" do
+      let!(:scheme) { create(:scheme) }
+      let!(:location) { create(:location, postcode: "AB1 2CD", mobility_type: "M", scheme:) }
+      let!(:duplicate_location) { create(:location, postcode: "AB1 2CD", mobility_type: "M", scheme:) }
+      let(:duplicate_sets) { described_class.duplicate_sets }
+
+      it "returns a list of duplicates for the same scheme" do
+        expect(duplicate_sets.count).to eq(1)
+        expect(duplicate_sets.first).to contain_exactly(location.id, duplicate_location.id)
+      end
+
+      context "when there is a deleted duplicate location" do
+        before do
+          create(:location, postcode: "AB1 2CD", mobility_type: "M", discarded_at: Time.zone.now, scheme:)
+        end
+
+        it "does not return the deleted location as a duplicate" do
+          expect(duplicate_sets.count).to eq(1)
+          expect(duplicate_sets.first).to contain_exactly(location.id, duplicate_location.id)
+        end
+      end
+
+      context "when there is a location with a different postcode" do
+        before do
+          create(:location, postcode: "A1 1AB", mobility_type: "M", scheme:)
+        end
+
+        it "does not return a location with a different postcode as a duplicate" do
+          expect(duplicate_sets.count).to eq(1)
+          expect(duplicate_sets.first).to contain_exactly(location.id, duplicate_location.id)
+        end
+      end
+
+      context "when there is a location with a different mobility_type" do
+        before do
+          create(:location, postcode: "AB1 2CD", mobility_type: "A", scheme:)
+        end
+
+        it "does not return a location with a different mobility_type as a duplicate" do
+          expect(duplicate_sets.count).to eq(1)
+          expect(duplicate_sets.first).to contain_exactly(location.id, duplicate_location.id)
+        end
+      end
+
+      context "when there is a location with a different scheme" do
+        before do
+          create(:location, postcode: "AB1 2CD", mobility_type: "M")
+        end
+
+        it "does not return a location with a different scheme as a duplicate" do
+          expect(duplicate_sets.count).to eq(1)
+          expect(duplicate_sets.first).to contain_exactly(location.id, duplicate_location.id)
+        end
+      end
+
+      context "when there is a location with nil values for duplicate check fields" do
+        before do
+          [location, duplicate_location].each do |l|
+            l.postcode = nil
+            l.mobility_type = nil
+            l.save!(validate: false)
+          end
+        end
+
+        it "does not return a location with nil values as a duplicate" do
+          expect(duplicate_sets).to be_empty
+        end
+      end
+    end
   end
 
   describe "status" do
diff --git a/spec/models/scheme_spec.rb b/spec/models/scheme_spec.rb
index 9b3db15a4..5ca529d3e 100644
--- a/spec/models/scheme_spec.rb
+++ b/spec/models/scheme_spec.rb
@@ -208,6 +208,135 @@ RSpec.describe Scheme, type: :model do
           end
         end
       end
+
+      context "when getting list of duplicate schemes" do
+        let(:organisation) { create(:organisation) }
+        let!(:scheme) { create(:scheme, :duplicate, owning_organisation: organisation) }
+        let!(:duplicate_scheme) { create(:scheme, :duplicate, owning_organisation: organisation) }
+        let(:duplicate_sets) { described_class.duplicate_sets }
+
+        it "returns a list of duplicates in the same organisation" do
+          expect(duplicate_sets.count).to eq(1)
+          expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+        end
+
+        context "when there is a deleted duplicate scheme" do
+          before do
+            create(:scheme, :duplicate, discarded_at: Time.zone.now)
+          end
+
+          it "does not return the deleted scheme as a duplicate" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+
+        context "when there is a scheme with a different scheme_type" do
+          before do
+            create(:scheme, :duplicate, scheme_type: 7)
+          end
+
+          it "does not return a scheme with a different scheme_type as a duplicate" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+
+        context "when there is a scheme with a different registered_under_care_act" do
+          before do
+            create(:scheme, :duplicate, registered_under_care_act: 2)
+          end
+
+          it "does not return a scheme with a different registered_under_care_act as a duplicate" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+
+        context "when there is a scheme with a different primary_client_group" do
+          before do
+            create(:scheme, :duplicate, primary_client_group: "H")
+          end
+
+          it "does not return a scheme with a different primary_client_group as a duplicate" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+
+        context "when there is a scheme with a different secondary_client_group" do
+          before do
+            create(:scheme, :duplicate, secondary_client_group: "O")
+          end
+
+          it "does not return a scheme with a different secondary_client_group as a duplicate" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+
+        context "when there is a scheme with a different has_other_client_group" do
+          before do
+            create(:scheme, :duplicate, has_other_client_group: 0)
+          end
+
+          it "does not return a scheme with a different has_other_client_group as a duplicate" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+
+        context "when there is a scheme with a different support_type" do
+          before do
+            create(:scheme, :duplicate, support_type: 4)
+          end
+
+          it "does not return a scheme with a different support_type as a duplicate" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+
+        context "when there is a scheme with a different intended_stay" do
+          before do
+            create(:scheme, :duplicate, intended_stay: "P")
+          end
+
+          it "does not return a scheme with a different intended_stay as a duplicate" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+
+        context "when there is a scheme with nil values for duplicate check fields" do
+          before do
+            [scheme, duplicate_scheme].each do |s|
+              s.scheme_type = nil
+              s.registered_under_care_act = nil
+              s.primary_client_group = nil
+              s.secondary_client_group = nil
+              s.has_other_client_group = nil
+              s.support_type = nil
+              s.intended_stay = nil
+              s.save!(validate: false)
+            end
+          end
+
+          it "does not return a scheme with nil values as a duplicate" do
+            expect(duplicate_sets).to be_empty
+          end
+        end
+
+        context "when there are duplicate schemes without secondary client group" do
+          let!(:scheme) { create(:scheme, :duplicate, owning_organisation: organisation, secondary_client_group: nil, has_other_client_group: 0) }
+          let!(:duplicate_scheme) { create(:scheme, :duplicate, owning_organisation: organisation, secondary_client_group: nil, has_other_client_group: 0) }
+
+          it "does not returns the duplicates" do
+            expect(duplicate_sets.count).to eq(1)
+            expect(duplicate_sets.first).to contain_exactly(scheme.id, duplicate_scheme.id)
+          end
+        end
+      end
     end
   end