diff --git a/corporate/tests/test_remote_billing.py b/corporate/tests/test_remote_billing.py
index 79f235fd87..015226e130 100644
--- a/corporate/tests/test_remote_billing.py
+++ b/corporate/tests/test_remote_billing.py
@@ -576,7 +576,8 @@ class LegacyServerLoginTest(BouncerTestCase):
         )
         self.assertEqual(result.status_code, 200)
         self.assert_in_success_response(
-            ["Did not find a server registration for this server_org_id."], result
+            ["This zulip_org_id is not registered with Zulip's billing management system."],
+            result,
         )
 
     def test_server_login_invalid_server_org_secret(self) -> None:
@@ -586,7 +587,7 @@ class LegacyServerLoginTest(BouncerTestCase):
             subdomain="selfhosting",
         )
         self.assertEqual(result.status_code, 200)
-        self.assert_in_success_response(["Invalid server_org_secret."], result)
+        self.assert_in_success_response(["Invalid zulip_org_key for this zulip_org_id."], result)
 
     def test_server_login_deactivated_server(self) -> None:
         self.server.deactivated = True
@@ -681,7 +682,7 @@ class LegacyServerLoginTest(BouncerTestCase):
             subdomain="selfhosting",
         )
         self.assertEqual(result.status_code, 200)
-        self.assert_in_success_response(["Invalid server_org_secret."], result)
+        self.assert_in_success_response(["Invalid zulip_org_key for this zulip_org_id."], result)
         # The next_page param should be preserved in the form.
         self.assert_in_success_response(
             ['<input type="hidden" name="next_page" value="billing" />'], result
diff --git a/corporate/views/remote_billing_page.py b/corporate/views/remote_billing_page.py
index 4a78cd90e2..8d2943c8ca 100644
--- a/corporate/views/remote_billing_page.py
+++ b/corporate/views/remote_billing_page.py
@@ -442,12 +442,16 @@ def remote_billing_legacy_server_login(
         remote_server = get_remote_server_by_uuid(server_org_id)
     except RemoteZulipServer.DoesNotExist:
         context.update(
-            {"error_message": _("Did not find a server registration for this server_org_id.")}
+            {
+                "error_message": _(
+                    "This zulip_org_id is not registered with Zulip's billing management system."
+                )
+            }
         )
         return render(request, "corporate/legacy_server_login.html", context)
 
     if not constant_time_compare(server_org_secret, remote_server.api_key):
-        context.update({"error_message": _("Invalid server_org_secret.")})
+        context.update({"error_message": _("Invalid zulip_org_key for this zulip_org_id.")})
         return render(request, "corporate/legacy_server_login.html", context)
 
     if remote_server.deactivated:
diff --git a/templates/corporate/legacy_server_login.html b/templates/corporate/legacy_server_login.html
index d3c53acea3..1931f10f05 100644
--- a/templates/corporate/legacy_server_login.html
+++ b/templates/corporate/legacy_server_login.html
@@ -27,17 +27,19 @@
                             </div>
                         </div>
                         <div class="input-box server-login-form-field">
-                            <label for="username" class="inline-block label-title">
+                            <label for="server-org-id" class="inline-block label-title">
                                 server_org_id
                                 <a href="https://zulip.readthedocs.io/en/stable/production/mobile-push-notifications.html" target="_blank">
                                     <i class="fa fa-question-circle-o" aria-hidden="true"></i>
                                 </a>
                             </label>
-                            <input id="username" name="server_org_id" class="required" type="text"/>
+                            <input id="server-org-id" name="server_org_id" class="required" type="text"/>
+                            <div class="alert alert-danger server-login-form-field-error server_org_id-error"></div>
                         </div>
                         <div class="input-box server-login-form-field">
                             <label for="password" class="inline-block label-title">server_org_key</label>
                             <input id="password" name="server_org_secret" class="required" type="password"/>
+                            <div class="alert alert-danger server-login-form-field-error server_org_secret-error"></div>
                         </div>
                         <div id="server-login-page-button-container">
                             <button type="submit" id="server-login-button" class="stripe-button-el invoice-button">
@@ -53,3 +55,4 @@
 </div>
 
 {% endblock %}
+
diff --git a/web/src/billing/remote_billing_auth.ts b/web/src/billing/remote_billing_auth.ts
index 6cf6602521..7fbddc9663 100644
--- a/web/src/billing/remote_billing_auth.ts
+++ b/web/src/billing/remote_billing_auth.ts
@@ -1,5 +1,32 @@
 import $ from "jquery";
 
+function handle_submit_for_server_login_form(form: HTMLFormElement): void {
+    // Get value of server_org_id.
+    const server_org_id = $<HTMLInputElement>("#server-org-id").val();
+    const $error_field = $(".server_org_id-error");
+    if (server_org_id === undefined) {
+        // Already handled by `validate` plugin.
+        return;
+    }
+
+    // Check if server_org_id is in UUID4 format.
+    // https://melvingeorge.me/blog/check-if-string-valid-uuid-regex-javascript
+    // Regex was modified by linter after copying from above link according to this rule:
+    // https://github.com/sindresorhus/eslint-plugin-unicorn/blob/main/docs/rules/better-regex.md
+    const is_valid_uuid = /^[\da-f]{8}(?:\b-[\da-f]{4}){3}\b-[\da-f]{12}$/gi;
+    // Check if server_org_id is in UUID4 format.
+    if (!is_valid_uuid.test(server_org_id)) {
+        $error_field.text(
+            "Wrong zulip_org_id format. Check to make sure zulip_org_id and zulip_org_key are not swapped.",
+        );
+        $error_field.show();
+        return;
+    }
+    $("#server-login-form").find(".loader").css("display", "inline-block");
+    $("#server-login-button .server-login-button-text").hide();
+    form.submit();
+}
+
 export function initialize(): void {
     $(
         "#server-login-form, #remote-billing-confirm-email-form, #remote-billing-confirm-login-form",
@@ -7,6 +34,11 @@ export function initialize(): void {
         errorClass: "text-error",
         wrapper: "div",
         submitHandler(form) {
+            if (form.id === "server-login-form") {
+                handle_submit_for_server_login_form(form);
+                return;
+            }
+
             $("#server-login-form").find(".loader").css("display", "inline-block");
             $("#server-login-button .server-login-button-text").hide();
             $("#remote-billing-confirm-email-form").find(".loader").css("display", "inline-block");
diff --git a/web/styles/portico/billing.css b/web/styles/portico/billing.css
index 3d448a0077..47a2177446 100644
--- a/web/styles/portico/billing.css
+++ b/web/styles/portico/billing.css
@@ -686,7 +686,10 @@ input[name="licenses"] {
 }
 
 #server-login-error {
-    text-align: center;
+    text-align: left;
+    margin: 0 auto;
+    max-width: 400px;
+    padding: 10px 25px;
 }
 
 #upgrade-page-details #due-today-for-future-update-wrapper {