diff --git a/CHANGELOG.md b/CHANGELOG.md
index 38f167e2..132e7f8b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@ All notable changes to this project will be documented in this file.
 - Webhooks support HTTP PUT (#249)
 - Webhooks can use different req. bodies and headers for "up" and "down" events. (#249)
 - Show check's code instead of full URL on 992px - 1200px wide screens. (#253)
+- Add WhatsApp integration (uses Twilio same as the SMS integration)
 
 ### Bug Fixes
 - Fix badges for tags containing special characters (#240, #237)
diff --git a/README.md b/README.md
index 6151fd76..25890c2d 100644
--- a/README.md
+++ b/README.md
@@ -127,6 +127,7 @@ Configurations settings loaded from environment variables:
 | TWILIO_ACCOUNT | `None`
 | TWILIO_AUTH | `None`
 | TWILIO_FROM | `None`
+| TWILIO_USE_WHATSAPP | `"False"`
 | PD_VENDOR_KEY | `None`
 | TRELLO_APP_KEY | `None`
 | MATRIX_HOMESERVER | `None`
diff --git a/hc/api/models.py b/hc/api/models.py
index 900045c1..08daa68c 100644
--- a/hc/api/models.py
+++ b/hc/api/models.py
@@ -39,6 +39,7 @@ CHANNEL_KINDS = (
     ("zendesk", "Zendesk"),
     ("trello", "Trello"),
     ("matrix", "Matrix"),
+    ("whatsapp", "WhatsApp"),
 )
 
 PO_PRIORITIES = {-2: "lowest", -1: "low", 0: "normal", 1: "high", 2: "emergency"}
@@ -328,6 +329,8 @@ class Channel(models.Model):
             return transports.Trello(self)
         elif self.kind == "matrix":
             return transports.Matrix(self)
+        elif self.kind == "whatsapp":
+            return transports.WhatsApp(self)
         else:
             raise NotImplementedError("Unknown channel kind: %s" % self.kind)
 
@@ -495,7 +498,7 @@ class Channel(models.Model):
 
     @property
     def sms_number(self):
-        assert self.kind == "sms"
+        assert self.kind in ("sms", "whatsapp")
         if self.value.startswith("{"):
             doc = json.loads(self.value)
             return doc["value"]
@@ -556,6 +559,18 @@ class Channel(models.Model):
         doc = json.loads(self.value)
         return doc.get("down")
 
+    @property
+    def whatsapp_notify_up(self):
+        assert self.kind == "whatsapp"
+        doc = json.loads(self.value)
+        return doc["up"]
+
+    @property
+    def whatsapp_notify_down(self):
+        assert self.kind == "whatsapp"
+        doc = json.loads(self.value)
+        return doc["down"]
+
 
 class Notification(models.Model):
     class Meta:
diff --git a/hc/api/tests/test_notify.py b/hc/api/tests/test_notify.py
index 6eac293a..0ce48d8d 100644
--- a/hc/api/tests/test_notify.py
+++ b/hc/api/tests/test_notify.py
@@ -522,7 +522,7 @@ class NotifyTestCase(BaseTestCase):
         mock_post.return_value.status_code = 200
 
         self.channel.notify(self.check)
-        assert Notification.objects.count() == 1
+        self.assertEqual(Notification.objects.count(), 1)
 
         args, kwargs = mock_post.call_args
         payload = kwargs["data"]
@@ -575,3 +575,51 @@ class NotifyTestCase(BaseTestCase):
 
         self.channel.notify(self.check)
         self.assertTrue(mock_post.called)
+
+    @patch("hc.api.transports.requests.request")
+    def test_whatsapp(self, mock_post):
+        definition = {"value": "+1234567890", "up": True, "down": True}
+
+        self._setup_data("whatsapp", json.dumps(definition))
+        self.check.last_ping = now() - td(hours=2)
+
+        mock_post.return_value.status_code = 200
+
+        self.channel.notify(self.check)
+        self.assertEqual(Notification.objects.count(), 1)
+
+        args, kwargs = mock_post.call_args
+        payload = kwargs["data"]
+        self.assertEqual(payload["To"], "whatsapp:+1234567890")
+
+        # sent SMS counter should go up
+        self.profile.refresh_from_db()
+        self.assertEqual(self.profile.sms_sent, 1)
+
+    @patch("hc.api.transports.requests.request")
+    def test_whatsapp_obeys_up_down_flags(self, mock_post):
+        definition = {"value": "+1234567890", "up": True, "down": False}
+
+        self._setup_data("whatsapp", json.dumps(definition))
+        self.check.last_ping = now() - td(hours=2)
+
+        self.channel.notify(self.check)
+        self.assertEqual(Notification.objects.count(), 0)
+
+        self.assertFalse(mock_post.called)
+
+    @patch("hc.api.transports.requests.request")
+    def test_whatsapp_limit(self, mock_post):
+        # At limit already:
+        self.profile.last_sms_date = now()
+        self.profile.sms_sent = 50
+        self.profile.save()
+
+        definition = {"value": "+1234567890", "up": True, "down": True}
+        self._setup_data("whatsapp", json.dumps(definition))
+
+        self.channel.notify(self.check)
+        self.assertFalse(mock_post.called)
+
+        n = Notification.objects.get()
+        self.assertTrue("Monthly message limit exceeded" in n.error)
diff --git a/hc/api/transports.py b/hc/api/transports.py
index f61b6cf0..07f92eac 100644
--- a/hc/api/transports.py
+++ b/hc/api/transports.py
@@ -415,6 +415,33 @@ class Sms(HttpTransport):
         return self.post(url, data=data, auth=auth)
 
 
+class WhatsApp(HttpTransport):
+    URL = "https://api.twilio.com/2010-04-01/Accounts/%s/Messages.json"
+
+    def is_noop(self, check):
+        if check.status == "down":
+            return not self.channel.whatsapp_notify_down
+        else:
+            return not self.channel.whatsapp_notify_up
+
+    def notify(self, check):
+        profile = Profile.objects.for_user(self.channel.project.owner)
+        if not profile.authorize_sms():
+            return "Monthly message limit exceeded"
+
+        url = self.URL % settings.TWILIO_ACCOUNT
+        auth = (settings.TWILIO_ACCOUNT, settings.TWILIO_AUTH)
+        text = tmpl("whatsapp_message.html", check=check, site_name=settings.SITE_NAME)
+
+        data = {
+            "From": "whatsapp:%s" % settings.TWILIO_FROM,
+            "To": "whatsapp:%s" % self.channel.sms_number,
+            "Body": text,
+        }
+
+        return self.post(url, data=data, auth=auth)
+
+
 class Trello(HttpTransport):
     URL = "https://api.trello.com/1/cards"
 
diff --git a/hc/front/forms.py b/hc/front/forms.py
index dda7af49..30494ade 100644
--- a/hc/front/forms.py
+++ b/hc/front/forms.py
@@ -133,6 +133,8 @@ class AddSmsForm(forms.Form):
     error_css_class = "has-error"
     label = forms.CharField(max_length=100, required=False)
     value = forms.CharField(max_length=16, validators=[phone_validator])
+    down = forms.BooleanField(required=False, initial=True)
+    up = forms.BooleanField(required=False, initial=True)
 
 
 class ChannelNameForm(forms.Form):
diff --git a/hc/front/tests/test_add_whatsapp.py b/hc/front/tests/test_add_whatsapp.py
new file mode 100644
index 00000000..8c5dbd1f
--- /dev/null
+++ b/hc/front/tests/test_add_whatsapp.py
@@ -0,0 +1,70 @@
+from django.test.utils import override_settings
+from hc.api.models import Channel
+from hc.test import BaseTestCase
+
+TEST_CREDENTIALS = {
+    "TWILIO_ACCOUNT": "foo",
+    "TWILIO_AUTH": "foo",
+    "TWILIO_FROM": "123",
+    "TWILIO_USE_WHATSAPP": True,
+}
+
+
+@override_settings(**TEST_CREDENTIALS)
+class AddWhatsAppTestCase(BaseTestCase):
+    url = "/integrations/add_whatsapp/"
+
+    def test_instructions_work(self):
+        self.client.login(username="alice@example.org", password="password")
+        r = self.client.get(self.url)
+        self.assertContains(r, "Get a WhatsApp message")
+
+    @override_settings(USE_PAYMENTS=True)
+    def test_it_warns_about_limits(self):
+        self.profile.sms_limit = 0
+        self.profile.save()
+
+        self.client.login(username="alice@example.org", password="password")
+        r = self.client.get(self.url)
+        self.assertContains(r, "upgrade to a")
+
+    def test_it_creates_channel(self):
+        form = {
+            "label": "My Phone",
+            "value": "+1234567890",
+            "down": "true",
+            "up": "true",
+        }
+
+        self.client.login(username="alice@example.org", password="password")
+        r = self.client.post(self.url, form)
+        self.assertRedirects(r, "/integrations/")
+
+        c = Channel.objects.get()
+        self.assertEqual(c.kind, "whatsapp")
+        self.assertEqual(c.sms_number, "+1234567890")
+        self.assertEqual(c.name, "My Phone")
+        self.assertTrue(c.whatsapp_notify_down)
+        self.assertTrue(c.whatsapp_notify_up)
+        self.assertEqual(c.project, self.project)
+
+    def test_it_obeys_up_down_flags(self):
+        form = {"label": "My Phone", "value": "+1234567890"}
+
+        self.client.login(username="alice@example.org", password="password")
+        r = self.client.post(self.url, form)
+        self.assertRedirects(r, "/integrations/")
+
+        c = Channel.objects.get()
+        self.assertEqual(c.kind, "whatsapp")
+        self.assertEqual(c.sms_number, "+1234567890")
+        self.assertEqual(c.name, "My Phone")
+        self.assertFalse(c.whatsapp_notify_down)
+        self.assertFalse(c.whatsapp_notify_up)
+        self.assertEqual(c.project, self.project)
+
+    @override_settings(TWILIO_USE_WHATSAPP=False)
+    def test_it_obeys_use_whatsapp_flag(self):
+        self.client.login(username="alice@example.org", password="password")
+        r = self.client.get(self.url)
+        self.assertEqual(r.status_code, 404)
diff --git a/hc/front/urls.py b/hc/front/urls.py
index 4bb6b004..d3643d4f 100644
--- a/hc/front/urls.py
+++ b/hc/front/urls.py
@@ -39,6 +39,7 @@ channel_urls = [
     path("telegram/bot/", views.telegram_bot, name="hc-telegram-webhook"),
     path("add_telegram/", views.add_telegram, name="hc-add-telegram"),
     path("add_sms/", views.add_sms, name="hc-add-sms"),
+    path("add_whatsapp/", views.add_whatsapp, name="hc-add-whatsapp"),
     path("add_trello/", views.add_trello, name="hc-add-trello"),
     path("add_trello/settings/", views.trello_settings, name="hc-trello-settings"),
     path("add_matrix/", views.add_matrix, name="hc-add-matrix"),
diff --git a/hc/front/views.py b/hc/front/views.py
index d9fa5837..8be9c81c 100644
--- a/hc/front/views.py
+++ b/hc/front/views.py
@@ -232,6 +232,7 @@ def index(request):
         "enable_discord": settings.DISCORD_CLIENT_ID is not None,
         "enable_telegram": settings.TELEGRAM_TOKEN is not None,
         "enable_sms": settings.TWILIO_AUTH is not None,
+        "enable_whatsapp": settings.TWILIO_USE_WHATSAPP,
         "enable_pd": settings.PD_VENDOR_KEY is not None,
         "enable_trello": settings.TRELLO_APP_KEY is not None,
         "enable_matrix": settings.MATRIX_ACCESS_TOKEN is not None,
@@ -603,6 +604,7 @@ def channels(request):
         "enable_discord": settings.DISCORD_CLIENT_ID is not None,
         "enable_telegram": settings.TELEGRAM_TOKEN is not None,
         "enable_sms": settings.TWILIO_AUTH is not None,
+        "enable_whatsapp": settings.TWILIO_USE_WHATSAPP,
         "enable_pd": settings.PD_VENDOR_KEY is not None,
         "enable_trello": settings.TRELLO_APP_KEY is not None,
         "enable_matrix": settings.MATRIX_ACCESS_TOKEN is not None,
@@ -1222,6 +1224,39 @@ def add_sms(request):
     return render(request, "integrations/add_sms.html", ctx)
 
 
+@login_required
+def add_whatsapp(request):
+    if not settings.TWILIO_USE_WHATSAPP:
+        raise Http404("whatsapp integration is not available")
+
+    if request.method == "POST":
+        form = AddSmsForm(request.POST)
+        if form.is_valid():
+            channel = Channel(project=request.project, kind="whatsapp")
+            channel.name = form.cleaned_data["label"]
+            channel.value = json.dumps(
+                {
+                    "value": form.cleaned_data["value"],
+                    "up": form.cleaned_data["up"],
+                    "down": form.cleaned_data["down"],
+                }
+            )
+            channel.save()
+
+            channel.assign_all_checks()
+            return redirect("hc-channels")
+    else:
+        form = AddSmsForm()
+
+    ctx = {
+        "page": "channels",
+        "project": request.project,
+        "form": form,
+        "profile": request.project.owner_profile,
+    }
+    return render(request, "integrations/add_whatsapp.html", ctx)
+
+
 @login_required
 def add_trello(request):
     if settings.TRELLO_APP_KEY is None:
diff --git a/hc/settings.py b/hc/settings.py
index 53f0e813..64946e59 100644
--- a/hc/settings.py
+++ b/hc/settings.py
@@ -187,10 +187,11 @@ PUSHBULLET_CLIENT_SECRET = os.getenv("PUSHBULLET_CLIENT_SECRET")
 TELEGRAM_BOT_NAME = os.getenv("TELEGRAM_BOT_NAME", "ExampleBot")
 TELEGRAM_TOKEN = os.getenv("TELEGRAM_TOKEN")
 
-# SMS (Twilio) integration
+# SMS and WhatsApp (Twilio) integration
 TWILIO_ACCOUNT = os.getenv("TWILIO_ACCOUNT")
 TWILIO_AUTH = os.getenv("TWILIO_AUTH")
 TWILIO_FROM = os.getenv("TWILIO_FROM")
+TWILIO_USE_WHATSAPP = envbool("TWILIO_USE_WHATSAPP", "False")
 
 # PagerDuty
 PD_VENDOR_KEY = os.getenv("PD_VENDOR_KEY")
diff --git a/static/img/integrations/whatsapp.png b/static/img/integrations/whatsapp.png
new file mode 100644
index 00000000..74eb6b95
Binary files /dev/null and b/static/img/integrations/whatsapp.png differ
diff --git a/templates/front/channels.html b/templates/front/channels.html
index c60585df..22400afe 100644
--- a/templates/front/channels.html
+++ b/templates/front/channels.html
@@ -15,8 +15,8 @@
 {% endif %}
 
 <div class="col-sm-12">
+    {% if channels %}
     <table class="table channels-table">
-        {% if channels %}
         <tr>
             <th></th>
             <th class="th-name">Name, Details</th>
@@ -90,6 +90,14 @@
                             list <span>{{ ch.trello_board_list|last }}</span>
                         {% elif ch.kind == "matrix" %}
                             Matrix <span>{{ ch.value }}</span>
+                        {% elif ch.kind == "whatsapp" %}
+                            WhatsApp to <span>{{ ch.sms_number }}</span>
+                            {% if ch.whatsapp_notify_down and not ch.whatsapp_notify_up %}
+                                (down only)
+                            {% endif %}
+                            {% if ch.whatsapp_notify_up and not ch.whatsapp_notify_down %}
+                                (up only)
+                            {% endif %}
                         {% else %}
                             {{ ch.kind }}
                         {% endif %}
@@ -127,7 +135,7 @@
                 {% else %}
                 Never
                 {% endif %}
-                {% if ch.kind == "sms" %}
+                {% if ch.kind == "sms" or ch.kind == "whatsapp" %}
                     <p>Used {{ profile.sms_sent_this_month }} of {{ profile.sms_limit }} sends this month.</p>
                 {% endif %}
             </td>
@@ -156,8 +164,12 @@
         </tr>
         {% endwith %}
         {% endfor %}
-        {% endif %}
     </table>
+    {% else %}
+        <div class="alert alert-info">
+            The project <strong>{{ project }}</strong> has no integrations set up yet.
+        </div>
+    {% endif %}
 
 
     <h1 class="ai-title">Add More</h1>
@@ -312,6 +324,17 @@
             <a href="{% url 'hc-add-matrix' %}" class="btn btn-primary">Add Integration</a>
         </li>
         {% endif %}
+        {% if enable_whatsapp %}
+        <li>
+            <img src="{% static 'img/integrations/whatsapp.png' %}"
+                class="icon" alt="WhatsApp icon" />
+
+            <h2>WhatsApp {% if use_payments %}<small>(paid plans)</small>{% endif %}</h2>
+            <p>Get a WhatsApp message when a check goes up or down.</p>
+
+            <a href="{% url 'hc-add-whatsapp' %}" class="btn btn-primary">Add Integration</a>
+        </li>
+        {% endif %}
         <li class="link-to-github">
             <img src="{% static 'img/integrations/missing.png' %}"
                  class="icon" alt="Suggest New Integration" />
diff --git a/templates/front/welcome.html b/templates/front/welcome.html
index f37fd4d4..049efa09 100644
--- a/templates/front/welcome.html
+++ b/templates/front/welcome.html
@@ -423,6 +423,15 @@
             </div>
         </div>
         {% endif %}
+
+        {% if enable_whatsapp %}
+        <div class="col-md-2 col-sm-4 col-xs-6">
+            <div class="integration">
+                <img src="{% static 'img/integrations/whatsapp.png' %}" class="icon" alt="WhatsApp icon" />
+                <h3>WhatsApp<br><small>Chat</small></h3>
+            </div>
+        </div>
+        {% endif %}
     </div>
 
     <div class="row tour-section">
diff --git a/templates/integrations/add_whatsapp.html b/templates/integrations/add_whatsapp.html
new file mode 100644
index 00000000..767390a2
--- /dev/null
+++ b/templates/integrations/add_whatsapp.html
@@ -0,0 +1,109 @@
+{% extends "base.html" %}
+{% load humanize static hc_extras %}
+
+{% block title %}Notification Channels - {% site_name %}{% endblock %}
+
+
+{% block content %}
+<div class="row">
+<div class="col-sm-12">
+    <h1>WhatsApp</h1>
+
+    <p>
+        Get a WhatsApp message when a check goes up or down.
+    </p>
+
+    {% if show_pricing and profile.sms_limit == 0 %}
+    <p class="alert alert-info">
+        <strong>Paid plan required.</strong>
+        WhatsApp messaging is not available on the free plan–sending the messages
+        cost too much! Please upgrade to a
+        <a href="{% url 'hc-billing' %}">paid plan</a> to enable WhatsApp messaging.
+    </p>
+    {% endif %}
+
+    <h2>Integration Settings</h2>
+
+    <form method="post" class="form-horizontal" action="{% url 'hc-add-whatsapp' %}">
+        {% csrf_token %}
+        <div class="form-group {{ form.label.css_classes }}">
+            <label for="id_label" class="col-sm-2 control-label">Label</label>
+            <div class="col-sm-6">
+                <input
+                    id="id_label"
+                    type="text"
+                    class="form-control"
+                    name="label"
+                    placeholder="Alice's Phone"
+                    value="{{ form.label.value|default:"" }}">
+
+                {% if form.label.errors %}
+                <div class="help-block">
+                    {{ form.label.errors|join:"" }}
+                </div>
+                {% else %}
+                <span class="help-block">
+                    Optional. If you add multiple phone numbers,
+                    the labels will help you tell them apart.
+                </span>
+                {% endif %}
+            </div>
+        </div>
+
+        <div class="form-group {{ form.value.css_classes }}">
+            <label for="id_number" class="col-sm-2 control-label">Phone Number</label>
+            <div class="col-sm-3">
+                <input
+                    id="id_number"
+                    type="tel"
+                    class="form-control"
+                    name="value"
+                    placeholder="+1234567890"
+                    value="{{ form.value.value|default:"" }}">
+
+                {% if form.value.errors %}
+                <div class="help-block">
+                    {{ form.value.errors|join:"" }}
+                </div>
+                {% else %}
+                <span class="help-block">
+                    Make sure the phone number starts with "+" and  has the
+                    country code.
+                </span>
+                {% endif %}
+            </div>
+        </div>
+
+        <div id="add-email-notify-group" class="form-group">
+            <label class="col-sm-2 control-label">Notify When</label>
+            <div class="col-sm-10">
+                <label class="checkbox-container">
+                    <input
+                        type="checkbox"
+                        name="down"
+                        value="true"
+                        {% if form.down.value %} checked {% endif %}>
+                    <span class="checkmark"></span>
+                    A check goes <strong>down</strong>
+                </label>
+                <label class="checkbox-container">
+                    <input
+                        type="checkbox"
+                        name="up"
+                        value="true"
+                        {% if form.up.value %} checked {% endif %}>
+                    <span class="checkmark"></span>
+                    A check goes <strong>up</strong>
+                </label>
+            </div>
+        </div>
+
+        <div class="form-group">
+            <div class="col-sm-offset-2 col-sm-10">
+                <button type="submit" class="btn btn-primary">Save Integration</button>
+            </div>
+        </div>
+    </form>
+</div>
+</div>
+{% endblock %}
diff --git a/templates/integrations/whatsapp_message.html b/templates/integrations/whatsapp_message.html
new file mode 100644
index 00000000..62505f5f
--- /dev/null
+++ b/templates/integrations/whatsapp_message.html
@@ -0,0 +1,7 @@
+{% load humanize %}{% spaceless %}
+{% if check.status == "down" %}
+    The check "{{ check.name_then_code }}" is DOWN. Last ping was {{ check.last_ping|naturaltime }}.
+{% else %}
+    The check "{{ check.name_then_code }}" is now UP.
+{% endif %}
+{% endspaceless %}
diff --git a/templates/payments/pricing.html b/templates/payments/pricing.html
index 6ad85264..abe85115 100644
--- a/templates/payments/pricing.html
+++ b/templates/payments/pricing.html
@@ -110,7 +110,7 @@
                     <li class="list-group-item">10 Team Members</li>
                     <li class="list-group-item">1000 Log Entries per Check</li>
                     <li class="list-group-item">API Access</li>
-                    <li class="list-group-item">50 SMS Alerts per Month</li>
+                    <li class="list-group-item">50 SMS &amp; WhatsApp Alerts per Month</li>
                     <li class="list-group-item">Email Support</li>
                 </ul>
                 {% if not request.user.is_authenticated %}
@@ -139,7 +139,7 @@
                     <li class="list-group-item">Unlimited Team Members</li>
                     <li class="list-group-item">1000 Log Entries per Check</li>
                     <li class="list-group-item">API Access</li>
-                    <li class="list-group-item">500 SMS Alerts per Month</li>
+                    <li class="list-group-item">500 SMS &amp; WhatsApp Alerts per Month</li>
                     <li class="list-group-item">Priority Email Support</li>
                 </ul>
                 {% if not request.user.is_authenticated %}