diff --git a/test/mv_web/live/join_live_email_failure_test.exs b/test/mv_web/live/join_live_email_failure_test.exs
index ef308c6..50a209c 100644
--- a/test/mv_web/live/join_live_email_failure_test.exs
+++ b/test/mv_web/live/join_live_email_failure_test.exs
@@ -2,6 +2,9 @@ defmodule MvWeb.JoinLiveEmailFailureTest do
   @moduledoc """
   When join confirmation email delivery fails, the user sees an error message
   and no success copy. Uses FailingMailAdapter; async: false to avoid config races.
+
+  Ensures SMTP is not configured (ENV cleared, Settings smtp_host nil) so that
+  Mailer.smtp_config/0 returns [] and the Application-configured FailingMailAdapter is used.
   """
   use MvWeb.ConnCase, async: false
   import Phoenix.LiveViewTest
@@ -12,18 +15,21 @@ defmodule MvWeb.JoinLiveEmailFailureTest do
   test "when confirmation email fails, user sees error flash and no success message", %{
     conn: conn
   } do
+    # Clear SMTP config so Mailer.smtp_config() returns [] and FailingMailAdapter is used.
+    saved_env = clear_smtp_env_and_save()
     enable_join_form_for_test()
 
-    saved = Application.get_env(:mv, Mv.Mailer)
+    saved_mailer = Application.get_env(:mv, Mv.Mailer)
 
     Application.put_env(
       :mv,
       Mv.Mailer,
-      Keyword.put(saved || [], :adapter, Mv.TestSupport.FailingMailAdapter)
+      Keyword.put(saved_mailer || [], :adapter, Mv.TestSupport.FailingMailAdapter)
     )
 
     on_exit(fn ->
-      Application.put_env(:mv, Mv.Mailer, saved)
+      Application.put_env(:mv, Mv.Mailer, saved_mailer)
+      restore_smtp_env(saved_env)
     end)
 
     {:ok, view, _html} = live(conn, "/join")
@@ -46,13 +52,36 @@ defmodule MvWeb.JoinLiveEmailFailureTest do
     refute view |> element("[data-testid='join-success-message']") |> has_element?()
   end
 
+  defp clear_smtp_env_and_save do
+    keys = [
+      "SMTP_HOST",
+      "SMTP_PORT",
+      "SMTP_USERNAME",
+      "SMTP_PASSWORD",
+      "SMTP_PASSWORD_FILE",
+      "SMTP_SSL"
+    ]
+
+    saved = for k <- keys, into: %{}, do: {k, System.get_env(k)}
+    for k <- keys, do: System.delete_env(k)
+    saved
+  end
+
+  defp restore_smtp_env(saved) do
+    for {k, v} <- saved do
+      if v != nil, do: System.put_env(k, v), else: System.delete_env(k)
+    end
+  end
+
   defp enable_join_form_for_test do
     {:ok, settings} = Membership.get_settings()
 
     Membership.update_settings(settings, %{
       join_form_enabled: true,
       join_form_field_ids: ["email", "first_name", "last_name"],
-      join_form_field_required: %{"email" => true, "first_name" => false, "last_name" => false}
+      join_form_field_required: %{"email" => true, "first_name" => false, "last_name" => false},
+      # Clear SMTP host so Mv.Config.smtp_configured?() is false and Mailer.smtp_config() returns [].
+      smtp_host: nil
     })
   end
 end