diff --git a/lib/towerops/agents/release_checker.ex b/lib/towerops/agents/release_checker.ex
index 47fa8663..c840ffd5 100644
--- a/lib/towerops/agents/release_checker.ex
+++ b/lib/towerops/agents/release_checker.ex
@@ -133,7 +133,9 @@ defmodule Towerops.Agents.ReleaseChecker do
   defp req_get(url, opts) do
     opts =
       if Application.get_env(:towerops, :env) == :test do
-        Keyword.put(opts, :plug, {Req.Test, __MODULE__})
+        opts
+        |> Keyword.put(:plug, {Req.Test, __MODULE__})
+        |> Keyword.put_new(:retry, false)
       else
         opts
       end
diff --git a/lib/towerops/billing/stripe_client.ex b/lib/towerops/billing/stripe_client.ex
index a8c50d01..0365df30 100644
--- a/lib/towerops/billing/stripe_client.ex
+++ b/lib/towerops/billing/stripe_client.ex
@@ -216,10 +216,14 @@ defmodule Towerops.Billing.StripeClient do
         decode_json: [keys: :strings]
       ] ++ opts
 
-    # Use Req.Test in test environment (following existing pattern)
+    # Use Req.Test in test environment (following existing pattern).
+    # Also disable retries in test so stubbed 5xx/429 responses return
+    # immediately instead of spending seconds retrying.
     req_opts =
       if Application.get_env(:towerops, :env) == :test do
-        Keyword.put(req_opts, :plug, {Req.Test, __MODULE__})
+        req_opts
+        |> Keyword.put(:plug, {Req.Test, __MODULE__})
+        |> Keyword.put_new(:retry, false)
       else
         req_opts
       end
diff --git a/lib/towerops/cn_maestro/client.ex b/lib/towerops/cn_maestro/client.ex
index 8e94f517..2c8a596b 100644
--- a/lib/towerops/cn_maestro/client.ex
+++ b/lib/towerops/cn_maestro/client.ex
@@ -165,8 +165,15 @@ defmodule Towerops.CnMaestro.Client do
     e -> {:error, Exception.message(e)}
   end
 
-  defp maybe_add_test_plug(opts), do: maybe_attach_test_plug(opts, Application.get_env(:towerops, :env))
+  defp maybe_add_test_plug(opts) do
+    opts
+    |> maybe_attach_test_plug(Application.get_env(:towerops, :env))
+    |> maybe_disable_retry(Application.get_env(:towerops, :env))
+  end
 
   defp maybe_attach_test_plug(opts, :test), do: Keyword.put(opts, :plug, {Req.Test, __MODULE__})
   defp maybe_attach_test_plug(opts, _env), do: opts
+
+  defp maybe_disable_retry(opts, :test), do: Keyword.put_new(opts, :retry, false)
+  defp maybe_disable_retry(opts, _env), do: opts
 end
diff --git a/lib/towerops/gaiia/client.ex b/lib/towerops/gaiia/client.ex
index a7c8d132..b8f30e39 100644
--- a/lib/towerops/gaiia/client.ex
+++ b/lib/towerops/gaiia/client.ex
@@ -318,7 +318,9 @@ defmodule Towerops.Gaiia.Client do
 
     req_opts =
       if Application.get_env(:towerops, :env) == :test do
-        Keyword.put(req_opts, :plug, {Req.Test, __MODULE__})
+        req_opts
+        |> Keyword.put(:plug, {Req.Test, __MODULE__})
+        |> Keyword.put_new(:retry, false)
       else
         req_opts
       end
diff --git a/lib/towerops/http.ex b/lib/towerops/http.ex
index 0230da42..6305b9c0 100644
--- a/lib/towerops/http.ex
+++ b/lib/towerops/http.ex
@@ -4,7 +4,7 @@ defmodule Towerops.HTTP do
   def request(owner, req_opts) when is_list(req_opts) do
     req_opts
     |> maybe_attach_test_plug(owner)
-    # |> maybe_disable_retry()  # Temporarily disabled to debug PagerDuty tests
+    |> maybe_disable_retry()
     |> Req.request()
   rescue
     error in RuntimeError ->
@@ -42,4 +42,15 @@ defmodule Towerops.HTTP do
       req_opts
     end
   end
+
+  # In test, disable Req's default retry-on-5xx/transient-error behavior.
+  # Without this, tests that stub an error status wait ~7s for retries to
+  # exhaust before the response is returned.
+  defp maybe_disable_retry(req_opts) do
+    if Application.get_env(:towerops, :env) == :test and !Keyword.has_key?(req_opts, :retry) do
+      Keyword.put(req_opts, :retry, false)
+    else
+      req_opts
+    end
+  end
 end
diff --git a/lib/towerops/preseem/client.ex b/lib/towerops/preseem/client.ex
index 6d19128c..e32e10d2 100644
--- a/lib/towerops/preseem/client.ex
+++ b/lib/towerops/preseem/client.ex
@@ -116,10 +116,13 @@ defmodule Towerops.Preseem.Client do
       headers: [{"accept", "application/json"}]
     ]
 
-    # Only use Req.Test plug in test environment
+    # Only use Req.Test plug in test environment; disable retry in tests
+    # so stubbed error statuses don't trigger a ~7s exponential backoff.
     opts =
       if Application.get_env(:towerops, :env) == :test do
-        Keyword.put(opts, :plug, {Req.Test, __MODULE__})
+        opts
+        |> Keyword.put(:plug, {Req.Test, __MODULE__})
+        |> Keyword.put_new(:retry, false)
       else
         opts
       end
diff --git a/lib/towerops/sonar/client.ex b/lib/towerops/sonar/client.ex
index 08e2b39b..0f113d63 100644
--- a/lib/towerops/sonar/client.ex
+++ b/lib/towerops/sonar/client.ex
@@ -159,7 +159,11 @@ defmodule Towerops.Sonar.Client do
       {:error, Exception.message(exception)}
   end
 
-  defp maybe_attach_test_plug(req_opts, :test), do: Keyword.put(req_opts, :plug, {Req.Test, __MODULE__})
+  defp maybe_attach_test_plug(req_opts, :test) do
+    req_opts
+    |> Keyword.put(:plug, {Req.Test, __MODULE__})
+    |> Keyword.put_new(:retry, false)
+  end
 
   defp maybe_attach_test_plug(req_opts, _env), do: req_opts
 
diff --git a/lib/towerops/splynx/client.ex b/lib/towerops/splynx/client.ex
index 685b8b1d..a9b2ee6c 100644
--- a/lib/towerops/splynx/client.ex
+++ b/lib/towerops/splynx/client.ex
@@ -76,7 +76,9 @@ defmodule Towerops.Splynx.Client do
 
     req_opts =
       if Application.get_env(:towerops, :env) == :test do
-        Keyword.put(req_opts, :plug, {Req.Test, __MODULE__})
+        req_opts
+        |> Keyword.put(:plug, {Req.Test, __MODULE__})
+        |> Keyword.put_new(:retry, false)
       else
         req_opts
       end
@@ -119,7 +121,9 @@ defmodule Towerops.Splynx.Client do
 
     req_opts =
       if Application.get_env(:towerops, :env) == :test do
-        Keyword.put(req_opts, :plug, {Req.Test, __MODULE__})
+        req_opts
+        |> Keyword.put(:plug, {Req.Test, __MODULE__})
+        |> Keyword.put_new(:retry, false)
       else
         req_opts
       end