diff --git a/frontend_tests/casper_tests/10-admin.js b/frontend_tests/casper_tests/10-admin.js
index fbd97b29b3..44b2f0a4c6 100644
--- a/frontend_tests/casper_tests/10-admin.js
+++ b/frontend_tests/casper_tests/10-admin.js
@@ -28,9 +28,9 @@ casper.then(function () {
     casper.test.info('Changing notifications stream to Verona by filtering with "verona"');
     casper.click("#id_realm_notifications_stream > button.dropdown-toggle");
 
-    casper.waitUntilVisible('ul.dropdown-menu', function () {
-        casper.sendKeys('.dropdown-search > input[type=text]', 'verona');
-        casper.click(".dropdown-list-body li.stream_name");
+    casper.waitUntilVisible('#id_realm_notifications_stream ul.dropdown-menu', function () {
+        casper.sendKeys('#id_realm_notifications_stream .dropdown-search > input[type=text]', 'verona');
+        casper.click("#id_realm_notifications_stream .dropdown-list-body li.stream_name");
     });
 
     casper.waitUntilVisible('#admin-realm-notifications-stream-status', function () {
@@ -49,6 +49,32 @@ casper.then(function () {
     });
 });
 
+// Test changing signup notifications stream
+casper.then(function () {
+    casper.test.info('Changing signup notifications stream to Verona by filtering with "verona"');
+    casper.click("#id_realm_signup_notifications_stream > button.dropdown-toggle");
+
+    casper.waitUntilVisible('#id_realm_signup_notifications_stream ul.dropdown-menu', function () {
+        casper.sendKeys('#id_realm_signup_notifications_stream .dropdown-search > input[type=text]', 'verona');
+        casper.click("#id_realm_signup_notifications_stream .dropdown-list-body li.stream_name");
+    });
+
+    casper.waitUntilVisible('#admin-realm-signup-notifications-stream-status', function () {
+        casper.test.assertSelectorHasText('#admin-realm-signup-notifications-stream-status',
+                                          'Signup notifications stream changed!');
+        casper.test.assertSelectorHasText('#realm_signup_notifications_stream_name', '#Verona');
+    });
+});
+
+casper.then(function () {
+    casper.click(".signup-notifications-stream-disable");
+    casper.waitUntilVisible('#admin-realm-signup-notifications-stream-status', function () {
+        casper.test.assertSelectorHasText('#admin-realm-signup-notifications-stream-status',
+                                          'Signup notifications stream disabled!');
+        casper.test.assertSelectorHasText('#realm_signup_notifications_stream_name', 'Disabled');
+    });
+});
+
 // Test permissions setting
 casper.then(function () {
     casper.click("li[data-section='organization-permissions']");
diff --git a/frontend_tests/node_tests/settings_org.js b/frontend_tests/node_tests/settings_org.js
index 85078c27b5..62be2124ca 100644
--- a/frontend_tests/node_tests/settings_org.js
+++ b/frontend_tests/node_tests/settings_org.js
@@ -387,6 +387,31 @@ function test_disable_notifications_stream(disable_notifications_stream) {
                  'translated: Failed to change notifications stream!');
 }
 
+function test_disable_signup_notifications_stream(disable_signup_notifications_stream) {
+    var success_callback;
+    var error_callback;
+    channel.patch = function (req) {
+        assert.equal(req.url, '/json/realm');
+        assert.equal(req.data.signup_notifications_stream_id, '-1');
+        success_callback = req.success;
+        error_callback = req.error;
+    };
+
+    disable_signup_notifications_stream();
+
+    var response_data = {
+        signup_notifications_stream_id: -1,
+    };
+
+    success_callback(response_data);
+    assert.equal($('#admin-realm-signup-notifications-stream-status').val(),
+                 'translated: Signup notifications stream disabled!');
+
+    error_callback({});
+    assert.equal($('#admin-realm-signup-notifications-stream-status').val(),
+                 'translated: Failed to change signup notifications stream!');
+}
+
 function test_change_allow_subdomains(change_allow_subdomains) {
     var ev = {
         stopPropagation: noop,
@@ -460,6 +485,7 @@ function test_change_allow_subdomains(change_allow_subdomains) {
     $('#id_realm_allow_message_editing').change = set_callback('change_message_editing');
     $('#submit-add-realm-domain').click = set_callback('add_realm_domain');
     $('.notifications-stream-disable').click = set_callback('disable_notifications_stream');
+    $('.signup-notifications-stream-disable').click = set_callback('disable_signup_notifications_stream');
 
     var submit_settings_form;
     var submit_permissions_form;
@@ -505,6 +531,7 @@ function test_change_allow_subdomains(change_allow_subdomains) {
     test_change_invite_required(callbacks.change_invite_required);
     test_change_message_editing(callbacks.change_message_editing);
     test_disable_notifications_stream(callbacks.disable_notifications_stream);
+    test_disable_signup_notifications_stream(callbacks.disable_signup_notifications_stream);
     test_change_allow_subdomains(change_allow_subdomains);
 }());
 
@@ -562,4 +589,19 @@ function test_change_allow_subdomains(change_allow_subdomains) {
     settings_org.render_notifications_stream_ui();
     assert.equal(elem.text(), 'translated: Disabled');
     assert(elem.hasClass('text-warning'));
+
+    elem = $('#realm_signup_notifications_stream_name');
+    stream_data.get_sub_by_id = function (stream_id) {
+        assert.equal(stream_id, 75);
+        return { name: 'some_stream' };
+    };
+    settings_org.render_signup_notifications_stream_ui(75);
+    assert.equal(elem.text(), '#some_stream');
+    assert(!elem.hasClass('text-warning'));
+
+    stream_data.get_sub_by_id = noop;
+    settings_org.render_signup_notifications_stream_ui();
+    assert.equal(elem.text(), 'translated: Disabled');
+    assert(elem.hasClass('text-warning'));
+
 }());
diff --git a/static/js/admin.js b/static/js/admin.js
index c26abd5ed2..9bd97ef1a7 100644
--- a/static/js/admin.js
+++ b/static/js/admin.js
@@ -51,6 +51,7 @@ function _setup_page() {
         realm_default_language: page_params.realm_default_language,
         realm_waiting_period_threshold: page_params.realm_waiting_period_threshold,
         realm_notifications_stream_id: page_params.realm_notifications_stream_id,
+        realm_signup_notifications_stream_id: page_params.realm_signup_notifications_stream_id,
         is_admin: page_params.is_admin,
         realm_icon_source: page_params.realm_icon_source,
         realm_icon_url: page_params.realm_icon_url,
diff --git a/static/js/server_events_dispatch.js b/static/js/server_events_dispatch.js
index 2dbf0bfcad..a001b1f334 100644
--- a/static/js/server_events_dispatch.js
+++ b/static/js/server_events_dispatch.js
@@ -69,6 +69,7 @@ exports.dispatch_normal_event = function dispatch_normal_event(event) {
             name: notifications.redraw_title,
             name_changes_disabled: settings_org.toggle_name_change_display,
             notifications_stream_id: noop,
+            signup_notifications_stream_id: noop,
             restricted_to_domain: noop,
             waiting_period_threshold: noop,
         };
@@ -83,6 +84,9 @@ exports.dispatch_normal_event = function dispatch_normal_event(event) {
             } else if (event.property === 'notifications_stream_id') {
                 settings_org.render_notifications_stream_ui(
                     page_params.realm_notifications_stream_id);
+            } else if (event.property === 'signup_notifications_stream_id') {
+                settings_org.render_signup_notifications_stream_ui(
+                    page_params.realm_signup_notifications_stream_id);
             }
         } else if (event.op === 'update_dict' && event.property === 'default') {
             _.each(event.data, function (value, key) {
@@ -193,6 +197,11 @@ exports.dispatch_normal_event = function dispatch_normal_event(event) {
                     settings_org.render_notifications_stream_ui(
                         page_params.realm_notifications_stream_id);
                 }
+                if (page_params.realm_signup_notifications_stream_id === stream.stream_id) {
+                    page_params.realm_signup_notifications_stream_id = -1;
+                    settings_org.render_signup_notifications_stream_ui(
+                        page_params.realm_signup_notifications_stream_id);
+                }
             });
         }
         break;
diff --git a/static/js/settings_org.js b/static/js/settings_org.js
index f600d6d0de..9cb5228cf1 100644
--- a/static/js/settings_org.js
+++ b/static/js/settings_org.js
@@ -139,7 +139,7 @@ exports.populate_notifications_stream_dropdown = function (stream_list) {
     var search_input = $("#id_realm_notifications_stream .dropdown-search > input[type=text]");
 
     list_render(dropdown_list_body, stream_list, {
-        name: "admin-realm-dropdown-stream-list",
+        name: "admin-realm-notifications-stream-dropdown-list",
         modifier: function (item) {
             return templates.render("admin-realm-dropdown-stream-list", { stream: item });
         },
@@ -165,6 +165,48 @@ exports.populate_notifications_stream_dropdown = function (stream_list) {
     });
 };
 
+exports.render_signup_notifications_stream_ui = function (stream_id) {
+    var elem = $('#realm_signup_notifications_stream_name');
+
+    var name = stream_data.maybe_get_stream_name(stream_id);
+
+    if (!name) {
+        elem.text(i18n.t("Disabled"));
+        elem.addClass("text-warning");
+        return;
+    }
+
+    // Happy path
+    elem.text('#' + name);
+    elem.removeClass('text-warning');
+};
+
+exports.populate_signup_notifications_stream_dropdown = function (stream_list) {
+    var dropdown_list_body = $("#id_realm_signup_notifications_stream .dropdown-list-body").expectOne();
+    var search_input = $("#id_realm_signup_notifications_stream .dropdown-search > input[type=text]");
+
+    list_render(dropdown_list_body, stream_list, {
+        name: "admin-realm-signup-notifications-stream-dropdown-list",
+        modifier: function (item) {
+            return templates.render("admin-realm-dropdown-stream-list", { stream: item });
+        },
+        filter: {
+            element: search_input,
+            callback: function (item, value) {
+                return item.name.toLowerCase().indexOf(value) >= 0;
+            },
+        },
+    }).init();
+
+    $("#id_realm_signup_notifications_stream .dropdown-search").click(function (e) {
+        e.stopPropagation();
+    });
+
+    $("#id_realm_signup_notifications_stream .dropdown-toggle").click(function () {
+        search_input.val("").trigger("input");
+    });
+};
+
 function property_type_status_element(element) {
     return $("#admin-realm-" + element.split('_').join('-') + "-status").expectOne();
 }
@@ -176,9 +218,12 @@ function _set_up() {
 
     // Populate notifications stream modal
     if (page_params.is_admin) {
-        exports.populate_notifications_stream_dropdown(stream_data.get_streams_for_settings_page());
+        var streams = stream_data.get_streams_for_settings_page();
+        exports.populate_notifications_stream_dropdown(streams);
+        exports.populate_signup_notifications_stream_dropdown(streams);
     }
     exports.render_notifications_stream_ui(page_params.realm_notifications_stream_id);
+    exports.render_signup_notifications_stream_ui(page_params.realm_signup_notifications_stream_id);
 
     // Populate realm domains
     exports.populate_realm_domains(page_params.realm_domains);
@@ -691,6 +736,52 @@ function _set_up() {
         update_notifications_stream(-1);
     });
 
+    var signup_notifications_stream_status = $("#admin-realm-signup-notifications-stream-status").expectOne();
+    function update_signup_notifications_stream(new_signup_notifications_stream_id) {
+        exports.render_signup_notifications_stream_ui(new_signup_notifications_stream_id);
+        signup_notifications_stream_status.hide();
+        var stringified_id = JSON.stringify(parseInt(new_signup_notifications_stream_id, 10));
+        var url = "/json/realm";
+        var data = {
+            signup_notifications_stream_id: stringified_id,
+        };
+
+        channel.patch({
+            url: url,
+            data: data,
+
+            success: function (response_data) {
+                if (response_data.signup_notifications_stream_id !== undefined) {
+                    if (response_data.signup_notifications_stream_id < 0) {
+                        ui_report.success(i18n.t("Signup notifications stream disabled!"), signup_notifications_stream_status);
+                    } else {
+                        ui_report.success(i18n.t("Signup notifications stream changed!"), signup_notifications_stream_status);
+                    }
+                }
+            },
+            error: function (xhr) {
+                ui_report.error(i18n.t("Failed to change signup notifications stream!"), xhr, signup_notifications_stream_status);
+            },
+        });
+    }
+
+    dropdown_menu = $("#id_realm_signup_notifications_stream .dropdown-menu");
+    $("#id_realm_signup_notifications_stream .dropdown-list-body").on("click keypress", ".stream_name", function (e) {
+        if (e.type === "keypress") {
+            if (e.which === 13) {
+               dropdown_menu.dropdown("toggle");
+            } else {
+                return;
+            }
+        }
+
+        update_signup_notifications_stream($(this).attr("data-stream-id"));
+    });
+
+    $(".signup-notifications-stream-disable").click(function () {
+        update_signup_notifications_stream(-1);
+    });
+
     function upload_realm_icon(file_input) {
         var form_data = new FormData();
 
diff --git a/static/styles/settings.css b/static/styles/settings.css
index 34137b42df..7c0ad87301 100644
--- a/static/styles/settings.css
+++ b/static/styles/settings.css
@@ -519,7 +519,8 @@ input[type=checkbox].inline-block {
     text-align: left;
 }
 
-#realm_notifications_stream_label > button {
+#realm_notifications_stream_label > button,
+#realm_signup_notifications_stream_label > button {
     margin: 0px 5px;
 }
 
@@ -1125,11 +1126,13 @@ input[type=checkbox].inline-block {
     border-radius: 0px;
 }
 
-#id_realm_notifications_stream .dropdown-search > input[type=text] {
+#id_realm_notifications_stream .dropdown-search > input[type=text],
+#id_realm_signup_notifications_stream .dropdown-search > input[type=text] {
     margin: 9px;
 }
 
-#id_realm_notifications_stream .dropdown-list-body {
+#id_realm_notifications_stream .dropdown-list-body,
+#id_realm_signup_notifications_stream .dropdown-list-body {
     position: relative;
     height: auto;
     max-height: 200px;
diff --git a/static/templates/settings/organization-settings-admin.handlebars b/static/templates/settings/organization-settings-admin.handlebars
index c8b727e932..3f25895d67 100644
--- a/static/templates/settings/organization-settings-admin.handlebars
+++ b/static/templates/settings/organization-settings-admin.handlebars
@@ -1,6 +1,7 @@
 <div id="organization-settings" data-name="organization-settings" class="settings-section">
     <form class="form-horizontal admin-realm-form org-settings-form">
         <div class="alert" id="admin-realm-notifications-stream-status"></div>
+        <div class="alert" id="admin-realm-signup-notifications-stream-status"></div>
         <div class="alert" id="admin-realm-default-language-status"></div>
 
         <div class="alert" id="admin-realm-inline-image-preview-status"></div>
@@ -150,7 +151,7 @@
         <div class="input-group">
             <label for="realm_notifications_stream" id="realm_notifications_stream_label" class="inline-block"
                 title="{{t 'The stream to which new stream notifications go to.' }}">
-                {{t "Notifications stream:" }}
+                {{t "New stream notifications:" }}
                 <span class="dropup actual-dropdown-menu" id="id_realm_notifications_stream"
                     name="realm_notifications_stream" aria-labelledby="realm_notifications_stream_label">
                     <button class="button small rounded dropdown-toggle" data-toggle="dropdown">
@@ -170,5 +171,28 @@
             {{/if}}
         </div>
 
+        <div class="input-group">
+            <label for="realm_signup_notifications_stream" id="realm_signup_notifications_stream_label" class="inline-block"
+                title="{{t 'The stream which new user signup notifications go to.' }}">
+                {{t "New user notifications:" }}
+                <span class="dropup actual-dropdown-menu" id="id_realm_signup_notifications_stream"
+                    name="realm_signup_notifications_stream" aria-labelledby="realm_signup_notifications_stream_label">
+                    <button class="button small rounded dropdown-toggle" data-toggle="dropdown">
+                        <span id="realm_signup_notifications_stream_name"></span>
+                        <i class="fa fa-pencil"></i>
+                    </button>
+                    <ul class="dropdown-menu" role="menu">
+                        <li class="dropdown-search" role="presentation">
+                            <input type="text" role="menuitem" placeholder="{{t 'Filter streams' }}" autofocus/>
+                        </li>
+                        <span class="dropdown-list-body"></span>
+                    </ul>
+                </span>
+            </label>
+            {{#if is_admin }}
+            <a class="signup-notifications-stream-disable">{{t "[Disable]" }}</a>
+            {{/if}}
+        </div>
+
     </form>
 </div>
diff --git a/zerver/lib/actions.py b/zerver/lib/actions.py
index 178b033c0d..7eb6972125 100644
--- a/zerver/lib/actions.py
+++ b/zerver/lib/actions.py
@@ -574,6 +574,18 @@ def do_set_realm_notifications_stream(realm, stream, stream_id):
     )
     send_event(event, active_user_ids(realm.id))
 
+def do_set_realm_signup_notifications_stream(realm, stream, stream_id):
+    # type: (Realm, Stream, int) -> None
+    realm.signup_notifications_stream = stream
+    realm.save(update_fields=['signup_notifications_stream'])
+    event = dict(
+        type="realm",
+        op="update",
+        property="signup_notifications_stream_id",
+        value=stream_id
+    )
+    send_event(event, active_user_ids(realm.id))
+
 def do_deactivate_realm(realm):
     # type: (Realm) -> None
     """
diff --git a/zerver/lib/events.py b/zerver/lib/events.py
index 32461c5ae3..ead78b37c6 100644
--- a/zerver/lib/events.py
+++ b/zerver/lib/events.py
@@ -172,6 +172,12 @@ def fetch_initial_state_data(user_profile, event_types, queue_id, client_gravata
         else:
             state['realm_notifications_stream_id'] = -1
 
+        if user_profile.realm.get_signup_notifications_stream():
+            signup_notifications_stream = user_profile.realm.get_signup_notifications_stream()
+            state['realm_signup_notifications_stream_id'] = signup_notifications_stream.id
+        else:
+            state['realm_signup_notifications_stream_id'] = -1
+
     if want('realm_domains'):
         state['realm_domains'] = get_realm_domains(user_profile.realm)
 
diff --git a/zerver/tests/test_events.py b/zerver/tests/test_events.py
index b7213f29ed..ff295695de 100644
--- a/zerver/tests/test_events.py
+++ b/zerver/tests/test_events.py
@@ -68,6 +68,7 @@ from zerver.lib.actions import (
     do_set_realm_property,
     do_set_user_display_setting,
     do_set_realm_notifications_stream,
+    do_set_realm_signup_notifications_stream,
     do_unmute_topic,
     do_update_embedded_data,
     do_update_message,
@@ -1354,6 +1355,24 @@ class EventsRegisterTest(ZulipTestCase):
             error = schema_checker('events[0]', events[0])
             self.assert_on_error(error)
 
+    def test_change_realm_signup_notifications_stream(self) -> None:
+        schema_checker = self.check_events_dict([
+            ('type', equals('realm')),
+            ('op', equals('update')),
+            ('property', equals('signup_notifications_stream_id')),
+            ('value', check_int),
+        ])
+
+        stream = get_stream("Rome", self.user_profile.realm)
+
+        for signup_notifications_stream, signup_notifications_stream_id in ((stream, stream.id), (None, -1)):
+            events = self.do_test(
+                lambda: do_set_realm_signup_notifications_stream(self.user_profile.realm,
+                                                                 signup_notifications_stream,
+                                                                 signup_notifications_stream_id))
+            error = schema_checker('events[0]', events[0])
+            self.assert_on_error(error)
+
     def test_change_is_admin(self) -> None:
         schema_checker = self.check_events_dict([
             ('type', equals('realm_user')),
diff --git a/zerver/tests/test_home.py b/zerver/tests/test_home.py
index 5f6adb7b9e..ab26e7e814 100644
--- a/zerver/tests/test_home.py
+++ b/zerver/tests/test_home.py
@@ -138,6 +138,7 @@ class HomeTest(ZulipTestCase):
             "realm_presence_disabled",
             "realm_restricted_to_domain",
             "realm_show_digest_email",
+            "realm_signup_notifications_stream_id",
             "realm_uri",
             "realm_user_groups",
             "realm_users",
@@ -387,6 +388,17 @@ class HomeTest(ZulipTestCase):
         user.save()
         return user
 
+    def test_signup_notifications_stream(self):
+        # type: () -> None
+        email = self.example_email("hamlet")
+        realm = get_realm('zulip')
+        realm.signup_notifications_stream = get_stream('Denmark', realm)
+        realm.save()
+        self.login(email)
+        result = self._get_home_page()
+        page_params = self._get_page_params(result)
+        self.assertEqual(page_params['realm_signup_notifications_stream_id'], get_stream('Denmark', realm).id)
+
     @slow('creating users and loading home page')
     def test_people(self) -> None:
         hamlet = self.example_user('hamlet')
diff --git a/zerver/tests/test_realm.py b/zerver/tests/test_realm.py
index 5a1936c55a..eb3006a050 100644
--- a/zerver/tests/test_realm.py
+++ b/zerver/tests/test_realm.py
@@ -201,6 +201,32 @@ class RealmTest(ZulipTestCase):
         do_deactivate_stream(notifications_stream)
         self.assertIsNone(realm.get_notifications_stream())
 
+    def test_change_signup_notifications_stream(self) -> None:
+        # We need an admin user.
+        email = 'iago@zulip.com'
+        self.login(email)
+
+        disabled_signup_notifications_stream_id = -1
+        req = dict(signup_notifications_stream_id = ujson.dumps(disabled_signup_notifications_stream_id))
+        result = self.client_patch('/json/realm', req)
+        self.assert_json_success(result)
+        realm = get_realm('zulip')
+        self.assertEqual(realm.signup_notifications_stream, None)
+
+        new_signup_notifications_stream_id = 4
+        req = dict(signup_notifications_stream_id = ujson.dumps(new_signup_notifications_stream_id))
+        result = self.client_patch('/json/realm', req)
+        self.assert_json_success(result)
+        realm = get_realm('zulip')
+        self.assertEqual(realm.signup_notifications_stream.id, new_signup_notifications_stream_id)
+
+        invalid_signup_notifications_stream_id = 1234
+        req = dict(signup_notifications_stream_id = ujson.dumps(invalid_signup_notifications_stream_id))
+        result = self.client_patch('/json/realm', req)
+        self.assert_json_error(result, 'Invalid stream id')
+        realm = get_realm('zulip')
+        self.assertNotEqual(realm.signup_notifications_stream.id, invalid_signup_notifications_stream_id)
+
     def test_get_default_signup_notifications_stream(self) -> None:
         realm = get_realm("zulip")
         verona = get_stream("verona", realm)
diff --git a/zerver/views/realm.py b/zerver/views/realm.py
index 74875d3b2d..748f7942f8 100644
--- a/zerver/views/realm.py
+++ b/zerver/views/realm.py
@@ -8,6 +8,7 @@ from zerver.lib.actions import (
     do_set_realm_message_editing,
     do_set_realm_authentication_methods,
     do_set_realm_notifications_stream,
+    do_set_realm_signup_notifications_stream,
     do_set_realm_property,
 )
 from zerver.lib.i18n import get_available_language_codes
@@ -40,8 +41,9 @@ def update_realm(request, user_profile, name=REQ(validator=check_string, default
                  waiting_period_threshold=REQ(converter=to_non_negative_int, default=None),
                  authentication_methods=REQ(validator=check_dict([]), default=None),
                  notifications_stream_id=REQ(validator=check_int, default=None),
+                 signup_notifications_stream_id=REQ(validator=check_int, default=None),
                  message_retention_days=REQ(converter=to_not_negative_int_or_none, default=None)):
-    # type: (HttpRequest, UserProfile, Optional[str], Optional[str], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[int], Optional[bool], Optional[str], Optional[int], Optional[Dict[Any,Any]], Optional[int], Optional[int]) -> HttpResponse
+    # type: (HttpRequest, UserProfile, Optional[str], Optional[str], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[bool], Optional[int], Optional[bool], Optional[str], Optional[int], Optional[Dict[Any,Any]], Optional[int], Optional[int], Optional[int]) -> HttpResponse
     realm = user_profile.realm
 
     # Additional validation/error checking beyond types go here, so
@@ -92,8 +94,8 @@ def update_realm(request, user_profile, name=REQ(validator=check_string, default
                                      message_content_edit_limit_seconds)
         data['allow_message_editing'] = allow_message_editing
         data['message_content_edit_limit_seconds'] = message_content_edit_limit_seconds
-    # Realm.notifications_stream is not a boolean, Text or integer field, and thus doesn't fit
-    # into the do_set_realm_property framework.
+    # Realm.notifications_stream and Realm.signup_notifications_stream are not boolean,
+    # Text or integer field, and thus doesn't fit into the do_set_realm_property framework.
     if notifications_stream_id is not None:
         if realm.notifications_stream is None or (realm.notifications_stream.id !=
                                                   notifications_stream_id):
@@ -105,4 +107,15 @@ def update_realm(request, user_profile, name=REQ(validator=check_string, default
                                               notifications_stream_id)
             data['notifications_stream_id'] = notifications_stream_id
 
+    if signup_notifications_stream_id is not None:
+        if realm.signup_notifications_stream is None or (realm.signup_notifications_stream.id !=
+                                                         signup_notifications_stream_id):
+            new_signup_notifications_stream = None
+            if signup_notifications_stream_id >= 0:
+                (new_signup_notifications_stream, recipient, sub) = access_stream_by_id(
+                    user_profile, signup_notifications_stream_id)
+            do_set_realm_signup_notifications_stream(realm, new_signup_notifications_stream,
+                                                     signup_notifications_stream_id)
+            data['signup_notifications_stream_id'] = signup_notifications_stream_id
+
     return json_success(data)