diff --git a/apprise/plugins/plivo.py b/apprise/plugins/plivo.py
index df2f428d..d4c97ef3 100644
--- a/apprise/plugins/plivo.py
+++ b/apprise/plugins/plivo.py
@@ -169,9 +169,8 @@ class NotifyPlivo(NotifyBase):
             self.logger.warning(msg)
             raise TypeError(msg)
 
-        # Store our source
-        self.source = '{}{}'.format(
-            '' if source[0] != '+' else '+', result['full'])
+        # Store our source; enforce E.164 format
+        self.source = f'+{result["full"]}'
 
         # Parse our targets
         self.targets = list()
@@ -181,9 +180,8 @@ class NotifyPlivo(NotifyBase):
                 # Validate targets and drop bad ones:
                 result = is_phone_no(target)
                 if result:
-                    # store valid phone number
-                    self.targets.append('{}{}'.format(
-                        '' if target[0] != '+' else '+', result['full']))
+                    # store valid phone number; enforce E.164 format
+                    self.targets.append(f'+{result["full"]}')
                     continue
 
                 self.logger.warning(
@@ -331,7 +329,7 @@ class NotifyPlivo(NotifyBase):
                 token=self.pprint(self.token, privacy, safe=''),
                 source=self.source,
                 targets='/'.join(
-                    [NotifyPlivo.quote(x, safe='') for x in self.targets]),
+                    [NotifyPlivo.quote(x, safe='+') for x in self.targets]),
                 params=NotifyPlivo.urlencode(params))
 
     def __len__(self):
diff --git a/test/test_plugin_plivo.py b/test/test_plugin_plivo.py
index 63a3b4b3..bb742a82 100644
--- a/test/test_plugin_plivo.py
+++ b/test/test_plugin_plivo.py
@@ -83,7 +83,7 @@ apprise_url_tests = (
     ('plivo://?id={}&token={}&from=15551233000&to=15551232000'.format(
         'a' * 25, 'a' * 40), {
             # Our expected url(privacy=True) startswith() response:
-            'privacy_url': 'plivo://a...a@a...a/15551233000/15551232000',
+            'privacy_url': 'plivo://a...a@a...a/+15551233000/+15551232000',
             # reference to to= and from=
             'instance': NotifyPlivo,
     }),
@@ -92,7 +92,7 @@ apprise_url_tests = (
          # reference to to= and from=
          'instance': NotifyPlivo,
          # Our expected url(privacy=True) startswith() response:
-         'privacy_url': 'plivo://a...a@a...a/15551233000/15551232123'}),
+         'privacy_url': 'plivo://a...a@a...a/+15551233000/+15551232123'}),
     ('plivo://{}@{}/15551232000'.format('a' * 25, 'a' * 40), {
         'instance': NotifyPlivo,
         # throw a bizzare code forcing us to fail to look it up