diff --git a/app/controllers/collection_resources_controller.rb b/app/controllers/collection_resources_controller.rb
index b11904b70..d8c17ad2a 100644
--- a/app/controllers/collection_resources_controller.rb
+++ b/app/controllers/collection_resources_controller.rb
@@ -102,10 +102,31 @@ class CollectionResourcesController < ApplicationController
     @collection_resource = CollectionResource.new(year:, log_type:)
   end
 
+  def create
+    return render_not_found unless current_user.support? && editable_collection_resource_years.include?(resource_params[:year].to_i)
+
+    @collection_resource = CollectionResource.new(resource_params)
+    @collection_resource.download_filename ||= @collection_resource.file&.original_filename
+
+    validate_file(@collection_resource.file)
+    return render "collection_resources/new" if @collection_resource.errors.any?
+
+    begin
+      CollectionResourcesService.new.upload_collection_resource(@collection_resource.download_filename, @collection_resource.file)
+      @collection_resource.save!
+    rescue StandardError
+      @collection_resource.errors.add(:file, :error_uploading)
+      return render "collection_resources/new"
+    end
+
+    flash[:notice] = "The #{@collection_resource.log_type} #{text_year_range_format(@collection_resource.year)} #{@collection_resource.display_name} is now available to users."
+    redirect_to collection_resources_path
+  end
+
 private
 
   def resource_params
-    params.require(:collection_resource).permit(:year, :log_type, :resource_type, :file)
+    params.require(:collection_resource).permit(:year, :log_type, :resource_type, :file, :mandatory, :display_name)
   end
 
   def download_resource(filename)
diff --git a/app/services/mandatory_collection_resources_service.rb b/app/services/mandatory_collection_resources_service.rb
index 8b34153e9..397e4b5d0 100644
--- a/app/services/mandatory_collection_resources_service.rb
+++ b/app/services/mandatory_collection_resources_service.rb
@@ -27,6 +27,7 @@ class MandatoryCollectionResourcesService
       year:,
       log_type:,
       download_filename: download_filename(resource_type, year, log_type),
+      mandatory: true,
     )
   end
 
diff --git a/spec/features/collection_resources_spec.rb b/spec/features/collection_resources_spec.rb
index 643f3537e..8435fa914 100644
--- a/spec/features/collection_resources_spec.rb
+++ b/spec/features/collection_resources_spec.rb
@@ -5,6 +5,9 @@ RSpec.describe "Collection resources" do
   let(:collection_resources_service) { instance_double(CollectionResourcesService, file_exists_on_s3?: true) }
 
   before do
+    # rubocop:disable RSpec/AnyInstance
+    allow_any_instance_of(CollectionResourcesHelper).to receive(:editable_collection_resource_years).and_return([2024, 2025])
+    # rubocop:enable RSpec/AnyInstance
     allow(CollectionResourcesService).to receive(:new).and_return(collection_resources_service)
     allow(collection_resources_service).to receive(:upload_collection_resource)
     allow(collection_resources_service).to receive(:get_file_metadata).and_return({ "content_type" => "application/pdf", "content_length" => 1000 })
@@ -165,4 +168,28 @@ RSpec.describe "Collection resources" do
       expect(page).to have_content("There was an error uploading this file.")
     end
   end
+
+  context "when uploading an additional resource" do
+    it "only allows excel files for lettings" do
+      expect(CollectionResource.count).to eq(0)
+
+      visit(new_collection_resource_path(year: 2025, log_type: "sales"))
+
+      click_button("Add resource")
+      expect(page).to have_content("Select which file to upload")
+
+      attach_file "file", file_fixture("pdf_file.pdf")
+      fill_in("collection_resource[display_name]", with: "some file")
+      click_button("Add resource")
+      expect(collection_resources_service).to have_received(:upload_collection_resource).with("pdf_file.pdf", anything)
+      expect(CollectionResource.count).to eq(1)
+      expect(CollectionResource.first.year).to eq(2025)
+      expect(CollectionResource.first.log_type).to eq("sales")
+      expect(CollectionResource.first.resource_type).to be_nil
+      expect(CollectionResource.first.mandatory).to be_falsey
+      expect(CollectionResource.first.released_to_user).to be_nil
+      expect(CollectionResource.first.display_name).to eq("some file")
+      expect(page).to have_content("The sales 2025 to 2026 some file is now available to users.")
+    end
+  end
 end
diff --git a/spec/requests/collection_resources_controller_spec.rb b/spec/requests/collection_resources_controller_spec.rb
index d6da21589..5877c67fd 100644
--- a/spec/requests/collection_resources_controller_spec.rb
+++ b/spec/requests/collection_resources_controller_spec.rb
@@ -540,4 +540,42 @@ RSpec.describe CollectionResourcesController, type: :request do
       end
     end
   end
+
+  describe "POST #collection_resources" do
+    let(:some_file) { File.open(file_fixture("blank_bulk_upload_sales.csv")) }
+    let(:params) { { collection_resource: { year: 2025, log_type: "sales", file: some_file, display_name: "some file" } } }
+
+    context "when user is not signed in" do
+      it "redirects to the sign in page" do
+        post collection_resources_path, params: params
+        expect(response).to redirect_to(new_user_session_path)
+      end
+    end
+
+    context "when user is signed in as a data coordinator" do
+      let(:user) { create(:user, :data_coordinator) }
+
+      before do
+        sign_in user
+      end
+
+      it "returns page not found" do
+        post collection_resources_path, params: params
+        expect(response).to have_http_status(:not_found)
+      end
+    end
+
+    context "when user is signed in as a data provider" do
+      let(:user) { create(:user, :data_provider) }
+
+      before do
+        sign_in user
+      end
+
+      it "returns page not found" do
+        post collection_resources_path, params: params
+        expect(response).to have_http_status(:not_found)
+      end
+    end
+  end
 end