diff --git a/client/app/pages/alert/AlertEdit.jsx b/client/app/pages/alert/AlertEdit.jsx
index 64bff87631..be3446c3ac 100644
--- a/client/app/pages/alert/AlertEdit.jsx
+++ b/client/app/pages/alert/AlertEdit.jsx
@@ -103,6 +103,8 @@ export default class AlertEdit extends React.Component {
                       setSubject={subject => onNotificationTemplateChange({ custom_subject: subject })}
                       body={options.custom_body}
                       setBody={body => onNotificationTemplateChange({ custom_body: body })}
+                      allowHtml={options.allow_html}
+                      setAllowHtml={allowHtml => onNotificationTemplateChange({ allow_html: allowHtml })}
                     />
                   </HorizontalFormItem>
                 </>
diff --git a/client/app/pages/alert/AlertNew.jsx b/client/app/pages/alert/AlertNew.jsx
index 9e128ed2fc..1392b8ceeb 100644
--- a/client/app/pages/alert/AlertNew.jsx
+++ b/client/app/pages/alert/AlertNew.jsx
@@ -70,6 +70,8 @@ export default class AlertNew extends React.Component {
                       setSubject={subject => onNotificationTemplateChange({ custom_subject: subject })}
                       body={options.custom_body}
                       setBody={body => onNotificationTemplateChange({ custom_body: body })}
+                      allowHtml={options.allow_html}
+                      setAllowHtml={allowHtml => onNotificationTemplateChange({ allow_html: allowHtml })}
                     />
                   </HorizontalFormItem>
                 </>
diff --git a/client/app/pages/alert/components/NotificationTemplate.jsx b/client/app/pages/alert/components/NotificationTemplate.jsx
index 5aa750207b..173c88f887 100644
--- a/client/app/pages/alert/components/NotificationTemplate.jsx
+++ b/client/app/pages/alert/components/NotificationTemplate.jsx
@@ -4,12 +4,14 @@ import { head, isEmpty, isNull, isUndefined } from "lodash";
 import Mustache from "mustache";
 
 import HelpTrigger from "@/components/HelpTrigger";
+import Tooltip from "@/components/Tooltip";
 import { Alert as AlertType, Query as QueryType } from "@/components/proptypes";
 
 import Input from "antd/lib/input";
 import Select from "antd/lib/select";
 import Modal from "antd/lib/modal";
 import Switch from "antd/lib/switch";
+import Checkbox from "antd/lib/checkbox";
 
 import "./NotificationTemplate.less";
 
@@ -30,7 +32,18 @@ function normalizeCustomTemplateData(alert, query, columnNames, resultValues) {
   };
 }
 
-function NotificationTemplate({ alert, query, columnNames, resultValues, subject, setSubject, body, setBody }) {
+function NotificationTemplate({
+  alert,
+  query,
+  columnNames,
+  resultValues,
+  subject,
+  setSubject,
+  body,
+  setBody,
+  allowHtml,
+  setAllowHtml,
+}) {
   const hasContent = !!(subject || body);
   const [enabled, setEnabled] = useState(hasContent ? 1 : 0);
   const [showPreview, setShowPreview] = useState(false);
@@ -49,6 +62,7 @@ function NotificationTemplate({ alert, query, columnNames, resultValues, subject
         onOk: () => {
           setSubject(null);
           setBody(null);
+          setAllowHtml(false);
           setEnabled(value);
           setShowPreview(false);
         },
@@ -100,6 +114,16 @@ function NotificationTemplate({ alert, query, columnNames, resultValues, subject
             <i className="fa fa-question-circle" aria-hidden="true" /> Formatting guide{" "}
             <span className="sr-only">(help)</span>
           </HelpTrigger>
+          <Checkbox
+            className="alert-template-allow-html"
+            checked={allowHtml}
+            onChange={e => setAllowHtml(e.target.checked)}
+            data-test="AlertTemplateAllowHTML">
+            Allow HTML content
+            <Tooltip title="Renders query values without escaping, so destination formatting comes through instead of appearing as literal text. Only enable for queries you trust.">
+              <i className="fa fa-question-circle" aria-hidden="true" />
+            </Tooltip>
+          </Checkbox>
         </div>
       )}
     </div>
@@ -115,11 +139,14 @@ NotificationTemplate.propTypes = {
   setSubject: PropTypes.func.isRequired,
   body: PropTypes.string,
   setBody: PropTypes.func.isRequired,
+  allowHtml: PropTypes.bool,
+  setAllowHtml: PropTypes.func.isRequired,
 };
 
 NotificationTemplate.defaultProps = {
   subject: "",
   body: "",
+  allowHtml: false,
 };
 
 export default NotificationTemplate;
diff --git a/client/app/pages/alert/components/NotificationTemplate.less b/client/app/pages/alert/components/NotificationTemplate.less
index 15a4907c34..661bba4bfe 100644
--- a/client/app/pages/alert/components/NotificationTemplate.less
+++ b/client/app/pages/alert/components/NotificationTemplate.less
@@ -33,4 +33,15 @@
   .alert-template-preview {
       margin: 0 0 0 5px !important;
   }
+
+  .alert-template-allow-html {
+      display: block;
+      margin-top: 8px;
+
+      .fa-question-circle {
+          margin-left: 5px;
+          color: rgba(0, 0, 0, 0.45);
+          cursor: help;
+      }
+  }
 }
\ No newline at end of file
diff --git a/redash/models/__init__.py b/redash/models/__init__.py
index 5f5918cd60..c51ea7fb8d 100644
--- a/redash/models/__init__.py
+++ b/redash/models/__init__.py
@@ -1051,7 +1051,7 @@ def evaluate(self):
     def subscribers(self):
         return User.query.join(AlertSubscription).filter(AlertSubscription.alert == self)
 
-    def render_template(self, template):
+    def render_template(self, template, escape=True):
         if template is None:
             return ""
 
@@ -1081,17 +1081,18 @@ def render_template(self, template):
             "QUERY_RESULT_COLS": data["columns"],
             "QUERY_RESULT_TABLE": result_table,
         }
-        return mustache_render_escape(template, context)
+        render = mustache_render_escape if escape else mustache_render
+        return render(template, context)
 
     @property
     def custom_body(self):
         template = self.options.get("custom_body", self.options.get("template"))
-        return self.render_template(template)
+        return self.render_template(template, escape=self.options.get("allow_html") is not True)
 
     @property
     def custom_subject(self):
         template = self.options.get("custom_subject")
-        return self.render_template(template)
+        return self.render_template(template, escape=self.options.get("allow_html") is not True)
 
     @property
     def groups(self):
diff --git a/tests/models/test_alerts.py b/tests/models/test_alerts.py
index fbd82dcce1..20b2157d16 100644
--- a/tests/models/test_alerts.py
+++ b/tests/models/test_alerts.py
@@ -216,3 +216,32 @@ def test_render_custom_alert_template_query_table(self):
         """
         result = alert.render_template(textwrap.dedent(custom_alert))
         self.assertMultiLineEqual(result, textwrap.dedent(expected))
+
+    def test_custom_body_escapes_html_by_default(self):
+        alert = self.create_alert(get_results("<b>bold</b>"))
+        alert.options["custom_body"] = "Value: {{QUERY_RESULT_VALUE}}"
+        self.assertEqual(alert.custom_body, "Value: &lt;b&gt;bold&lt;/b&gt;")
+
+    def test_custom_body_renders_html_when_allow_html_enabled(self):
+        alert = self.create_alert(get_results("<b>bold</b>"))
+        alert.options["custom_body"] = "Value: {{QUERY_RESULT_VALUE}}"
+        alert.options["allow_html"] = True
+        self.assertEqual(alert.custom_body, "Value: <b>bold</b>")
+
+    def test_custom_subject_respects_allow_html(self):
+        alert = self.create_alert(get_results("<b>bold</b>"))
+        alert.options["custom_subject"] = "{{QUERY_RESULT_VALUE}}"
+        self.assertEqual(alert.custom_subject, "&lt;b&gt;bold&lt;/b&gt;")
+        alert.options["allow_html"] = True
+        self.assertEqual(alert.custom_subject, "<b>bold</b>")
+
+    def test_allow_html_does_not_affect_default_render_template(self):
+        alert = self.create_alert(get_results("<b>bold</b>"))
+        alert.options["allow_html"] = True
+        self.assertEqual(alert.render_template("{{QUERY_RESULT_VALUE}}"), "&lt;b&gt;bold&lt;/b&gt;")
+
+    def test_allow_html_requires_boolean_true(self):
+        alert = self.create_alert(get_results("<b>bold</b>"))
+        alert.options["custom_body"] = "Value: {{QUERY_RESULT_VALUE}}"
+        alert.options["allow_html"] = "false"
+        self.assertEqual(alert.custom_body, "Value: &lt;b&gt;bold&lt;/b&gt;")