diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2b16f3c6..6ddf299b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ Setup:
 Control Panel:
 
 * The users page now documents that passwords should only have ASCII characters to prevent character encoding mismaches between clients and the server.
+* The users page no longer shows user mailbox sizes because this was extremely slow for very large mailboxes.
 
 v0.29 (October 25, 2018)
 ------------------------
diff --git a/management/daemon.py b/management/daemon.py
index 2e23c8aa..334749e4 100755
--- a/management/daemon.py
+++ b/management/daemon.py
@@ -146,7 +146,7 @@ def me():
 @authorized_personnel_only
 def mail_users():
 	if request.args.get("format", "") == "json":
-		return json_response(get_mail_users_ex(env, with_archived=True, with_slow_info=True))
+		return json_response(get_mail_users_ex(env, with_archived=True))
 	else:
 		return "".join(x+"\n" for x in get_mail_users(env))
 
diff --git a/management/mailconfig.py b/management/mailconfig.py
index 82c922e4..28e1c623 100755
--- a/management/mailconfig.py
+++ b/management/mailconfig.py
@@ -105,7 +105,7 @@ def get_mail_users(env):
 	users = [ row[0] for row in c.fetchall() ]
 	return utils.sort_email_addresses(users, env)
 
-def get_mail_users_ex(env, with_archived=False, with_slow_info=False):
+def get_mail_users_ex(env, with_archived=False):
 	# Returns a complex data structure of all user accounts, optionally
 	# including archived (status="inactive") accounts.
 	#
@@ -139,9 +139,6 @@ def get_mail_users_ex(env, with_archived=False, with_slow_info=False):
 		}
 		users.append(user)
 
-		if with_slow_info:
-			user["mailbox_size"] = utils.du(os.path.join(env['STORAGE_ROOT'], 'mail/mailboxes', *reversed(email.split("@"))))
-
 	# Add in archived accounts.
 	if with_archived:
 		root = os.path.join(env['STORAGE_ROOT'], 'mail/mailboxes')
@@ -158,8 +155,6 @@ def get_mail_users_ex(env, with_archived=False, with_slow_info=False):
 						"mailbox": mbox,
 					}
 					users.append(user)
-					if with_slow_info:
-						user["mailbox_size"] = utils.du(mbox)
 
 	# Group by domain.
 	domains = { }
diff --git a/management/templates/users.html b/management/templates/users.html
index c70ac0da..dee79d42 100644
--- a/management/templates/users.html
+++ b/management/templates/users.html
@@ -43,7 +43,6 @@
     <tr>
       <th width="50%">Email Address</th>
       <th>Actions</th>
-      <th>Mailbox Size</th>
     </tr>
   </thead>
   <tbody>
@@ -73,8 +72,6 @@
           archive account
         </a>
     </td>
-    <td class='mailboxsize'>
-    </td>
   </tr>
   <tr id="user-extra-template" class="if_inactive">
     <td colspan="3" style="border: 0; padding-top: 0">
@@ -156,7 +153,6 @@ function show_users() {
 
           n.attr('data-email', user.email);
           n.find('.address').text(user.email)
-          n.find('.mailboxsize').text(nice_size(user.mailbox_size))
           n2.find('.restore_info tt').text(user.mailbox);
 
           if (user.status == 'inactive') continue;