diff --git a/app/Constants.php b/app/Constants.php
index 03c07fa58b..51e19f5451 100644
--- a/app/Constants.php
+++ b/app/Constants.php
@@ -158,6 +158,7 @@ if (! defined('APP_NAME')) {
     define('MAX_DOCUMENT_SIZE', env('MAX_DOCUMENT_SIZE', 10000)); // KB
     define('MAX_EMAIL_DOCUMENTS_SIZE', env('MAX_EMAIL_DOCUMENTS_SIZE', 10000)); // Total KB
     define('MAX_ZIP_DOCUMENTS_SIZE', env('MAX_EMAIL_DOCUMENTS_SIZE', 30000)); // Total KB (uncompressed)
+    define('MAX_EMAILS_SENT_PER_HOUR', 90);
     define('DOCUMENT_PREVIEW_SIZE', env('DOCUMENT_PREVIEW_SIZE', 300)); // pixels
     define('DEFAULT_FONT_SIZE', 9);
     define('DEFAULT_HEADER_FONT', 1); // Roboto
diff --git a/app/Ninja/Mailers/ContactMailer.php b/app/Ninja/Mailers/ContactMailer.php
index 79ac13650d..50dbb87279 100644
--- a/app/Ninja/Mailers/ContactMailer.php
+++ b/app/Ninja/Mailers/ContactMailer.php
@@ -379,7 +379,7 @@ class ContactMailer extends Mailer
 
         // http://stackoverflow.com/questions/1375501/how-do-i-throttle-my-sites-api-users
         $hour = 60 * 60;
-        $hour_limit = 50; // users are limited to 50 emails/hour
+        $hour_limit = MAX_EMAILS_SENT_PER_HOUR;
         $hour_throttle = Cache::get("email_hour_throttle:{$key}", null);
         $last_api_request = Cache::get("last_email_request:{$key}", 0);
         $last_api_diff = time() - $last_api_request;