diff --git a/app/controllers/concerns/providers/application_dependable.rb b/app/controllers/concerns/providers/application_dependable.rb
index 6291accf75..2461969205 100644
--- a/app/controllers/concerns/providers/application_dependable.rb
+++ b/app/controllers/concerns/providers/application_dependable.rb
@@ -16,8 +16,9 @@ def legal_aid_application_not_required?
       before_action :encode_upload_header
       before_action :set_legal_aid_application
 
+      # Let ActiveRecord::RecordNotFound bubble up for handling by exceptions_app as a 404
       def legal_aid_application
-        @legal_aid_application ||= LegalAidApplication.find_by(id: params[:legal_aid_application_id])
+        @legal_aid_application ||= LegalAidApplication.find(params[:legal_aid_application_id])
       end
       delegate :applicant, to: :legal_aid_application
 
@@ -25,15 +26,10 @@ def legal_aid_application
 
       def set_legal_aid_application
         return if self.class.legal_aid_application_not_required?
-        return process_invalid_application if legal_aid_application.blank?
 
         legal_aid_application.update!(provider_step:, provider_step_params:) unless provider_step == :delete
       end
 
-      def process_invalid_application
-        redirect_to error_path(:page_not_found)
-      end
-
       def provider_step_params
         params.except(:action, :controller, :legal_aid_application_id)
       end
diff --git a/spec/policies/provider_access_spec.rb b/spec/policies/provider_access_spec.rb
index df86b2ca1a..5db85c9e4f 100644
--- a/spec/policies/provider_access_spec.rb
+++ b/spec/policies/provider_access_spec.rb
@@ -27,11 +27,12 @@
     expect(response).to redirect_to(error_path(:access_denied))
   end
 
-  it "allows missing application to be caught by not found" do
+  it "allows missing application to be caught by not found", :show_exceptions do
     login_as other_provider
 
     get providers_legal_aid_application_correspondence_address_lookup_path(SecureRandom.uuid)
 
-    expect(response).to redirect_to(error_path(:page_not_found))
+    expect(response).to have_http_status(:not_found)
+    expect(response).to render_template("errors/show/_page_not_found")
   end
 end
diff --git a/spec/requests/errors_controller_spec.rb b/spec/requests/errors_controller_spec.rb
index 2426acb112..447c89f462 100644
--- a/spec/requests/errors_controller_spec.rb
+++ b/spec/requests/errors_controller_spec.rb
@@ -57,7 +57,7 @@
     let(:get_invalid_id) { get feedback_path(SecureRandom.uuid) }
 
     context "with default locale" do
-      it "responds with http status" do
+      it "responds with expected http status" do
         get_invalid_id
         expect(response).to have_http_status(:not_found)
       end
@@ -77,6 +77,23 @@
     end
   end
 
+  context "when page not found due to legal_aid_application not found" do
+    let(:get_invalid_id) { get providers_legal_aid_application_previous_references_path(legal_aid_application_id: SecureRandom.uuid) }
+    let(:provider) { create(:provider) }
+
+    before { sign_in provider }
+
+    it "responds with expected http status" do
+      get_invalid_id
+      expect(response).to have_http_status(:not_found)
+    end
+
+    it "renders page not found" do
+      get_invalid_id
+      expect(response).to render_template("errors/show/_page_not_found")
+    end
+  end
+
   context "when internal server error/500 due to code fault" do
     let(:get_invalid_id) { get feedback_path(SecureRandom.uuid) }
 
diff --git a/spec/requests/providers/about_the_financial_assessments_controller_spec.rb b/spec/requests/providers/about_the_financial_assessments_controller_spec.rb
index fd8dbd71f1..0ed05781ec 100644
--- a/spec/requests/providers/about_the_financial_assessments_controller_spec.rb
+++ b/spec/requests/providers/about_the_financial_assessments_controller_spec.rb
@@ -33,11 +33,13 @@
         expect(unescaped_response_body).to include(I18n.t("providers.about_the_financial_assessments.show.title"))
       end
 
-      context "when the application does not exist" do
+      context "when the application does not exist", :show_exceptions do
         let(:application_id) { SecureRandom.uuid }
 
-        it "redirects to an error" do
-          expect(response).to redirect_to(error_path(:page_not_found))
+        it "renders page not found page" do
+          expect(response)
+            .to have_http_status(:not_found)
+            .and render_template("errors/show/_page_not_found")
         end
       end
 
@@ -83,7 +85,7 @@
         login_as application.provider
       end
 
-      context "when the application does not exist" do
+      context "when the application does not exist", :show_exceptions do
         let(:application_id) { SecureRandom.uuid }
 
         it "redirects to and error page without calling the email service" do
@@ -91,7 +93,9 @@
 
           submit_patch
 
-          expect(response).to redirect_to(error_path(:page_not_found))
+          expect(response)
+            .to have_http_status(:not_found)
+            .and render_template("errors/show/_page_not_found")
         end
       end
 
diff --git a/spec/requests/providers/check_merits_answers_spec.rb b/spec/requests/providers/check_merits_answers_spec.rb
index ce1ceb13a4..ec4c3af82c 100644
--- a/spec/requests/providers/check_merits_answers_spec.rb
+++ b/spec/requests/providers/check_merits_answers_spec.rb
@@ -228,7 +228,7 @@
       context "when there are required document categories" do
         before do
           allow(LegalFramework::MeritsTasksService).to receive(:call).with(application).and_return(smtl)
-          allow(LegalAidApplication).to receive(:find_by).and_return(application)
+          allow(LegalAidApplication).to receive(:find).and_return(application)
           allow(application).to receive(:evidence_is_required?).and_return(true)
         end