diff --git a/CHANGELOG.md b/CHANGELOG.md
index feac5dfe..125a54d6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ All notable changes to this project will be documented in this file.
 - Reduce the number of SQL queries used in the "Get Checks" API call
 - Add support for script's exit status in ping URLs (#429)
 - Improve phone number sanitization: remove spaces and hyphens
+- Change the "Test Integration" behavior for webhooks: don't retry failed requests
 
 ## v1.17.0 - 2020-10-14
 
diff --git a/hc/api/models.py b/hc/api/models.py
index 52d4a562..bc2cda39 100644
--- a/hc/api/models.py
+++ b/hc/api/models.py
@@ -489,7 +489,8 @@ class Channel(models.Model):
         n.save()
 
         # These are not database fields. It is just a convenient way to pass
-        # status_url to transport classes.
+        # status_url and the is_test flag to transport classes.
+        check.is_test = is_test
         check.status_url = n.status_url()
 
         error = self.transport.notify(check) or ""
diff --git a/hc/api/tests/test_notify.py b/hc/api/tests/test_notify.py
index deae430c..637966da 100644
--- a/hc/api/tests/test_notify.py
+++ b/hc/api/tests/test_notify.py
@@ -58,6 +58,9 @@ class NotifyTestCase(BaseTestCase):
         self._setup_data("webhook", json.dumps(definition))
         self.channel.notify(self.check)
 
+        # The transport should have retried 3 times
+        self.assertEqual(mock_get.call_count, 3)
+
         n = Notification.objects.get()
         self.assertEqual(n.error, "Connection timed out")
 
@@ -75,6 +78,9 @@ class NotifyTestCase(BaseTestCase):
         self._setup_data("webhook", json.dumps(definition))
         self.channel.notify(self.check)
 
+        # The transport should have retried 3 times
+        self.assertEqual(mock_get.call_count, 3)
+
         n = Notification.objects.get()
         self.assertEqual(n.error, "Connection failed")
 
@@ -92,9 +98,30 @@ class NotifyTestCase(BaseTestCase):
 
         self.channel.notify(self.check)
 
+        # The transport should have retried 3 times
+        self.assertEqual(mock_get.call_count, 3)
+
         n = Notification.objects.get()
         self.assertEqual(n.error, "Received status code 500")
 
+    @patch("hc.api.transports.requests.request", side_effect=Timeout)
+    def test_webhooks_dont_retry_when_sending_test_notifications(self, mock_get):
+        definition = {
+            "method_down": "GET",
+            "url_down": "http://example",
+            "body_down": "",
+            "headers_down": {},
+        }
+
+        self._setup_data("webhook", json.dumps(definition))
+        self.channel.notify(self.check, is_test=True)
+
+        # is_test flag is set, the transport should not retry:
+        self.assertEqual(mock_get.call_count, 1)
+
+        n = Notification.objects.get()
+        self.assertEqual(n.error, "Connection timed out")
+
     @patch("hc.api.transports.requests.request")
     def test_webhooks_support_variables(self, mock_get):
         definition = {
diff --git a/hc/api/transports.py b/hc/api/transports.py
index ba0f1006..4da12981 100644
--- a/hc/api/transports.py
+++ b/hc/api/transports.py
@@ -169,9 +169,8 @@ class HttpTransport(Transport):
             return "Connection failed"
 
     @classmethod
-    def get(cls, url, **kwargs):
-        # Make 3 attempts--
-        for x in range(0, 3):
+    def get(cls, url, num_tries=3, **kwargs):
+        for x in range(0, num_tries):
             error = cls._request("get", url, **kwargs)
             if error is None:
                 break
@@ -179,9 +178,8 @@ class HttpTransport(Transport):
         return error
 
     @classmethod
-    def post(cls, url, **kwargs):
-        # Make 3 attempts--
-        for x in range(0, 3):
+    def post(cls, url, num_tries=3, **kwargs):
+        for x in range(0, num_tries):
             error = cls._request("post", url, **kwargs)
             if error is None:
                 break
@@ -189,9 +187,8 @@ class HttpTransport(Transport):
         return error
 
     @classmethod
-    def put(cls, url, **kwargs):
-        # Make 3 attempts--
-        for x in range(0, 3):
+    def put(cls, url, num_tries=3, **kwargs):
+        for x in range(0, num_tries):
             error = cls._request("put", url, **kwargs)
             if error is None:
                 break
@@ -240,14 +237,19 @@ class Webhook(HttpTransport):
 
         body = spec["body"]
         if body:
-            body = self.prepare(body, check)
+            body = self.prepare(body, check).encode()
+
+        num_tries = 3
+        if getattr(check, "is_test"):
+            # When sending a test notification, don't retry on failures.
+            num_tries = 1
 
         if spec["method"] == "GET":
-            return self.get(url, headers=headers)
+            return self.get(url, num_tries=num_tries, headers=headers)
         elif spec["method"] == "POST":
-            return self.post(url, data=body.encode(), headers=headers)
+            return self.post(url, num_tries=num_tries, data=body, headers=headers)
         elif spec["method"] == "PUT":
-            return self.put(url, data=body.encode(), headers=headers)
+            return self.put(url, num_tries=num_tries, data=body, headers=headers)
 
 
 class Slack(HttpTransport):