My Mail Assure Bill is higher than I expected

Last Modified

Wed May 24 12:45 GMT 2023


  • My Mail Assure Bill is higher than I expected
  • The Mail Assure invoice is higher than expected, with more mailboxes being billed for, than are in use.


  • Mail Assure


  • Mail Assure and your mail server must be configured correctly for accurate invoicing.

    • By default, Mail Assure will filter every email received (inbound and outbound) - this can result in inaccurate invoicing, as the invoice is for the number of filtered or archived mailboxes.
    • To check what is being charged for, this is listed after the summary on the product invoice.
  • To check for correct configuration (per domain):
    1. Navigate to Domains Overview.
    2. Select the domain with higher usage than expected.
    3. Select "Mailboxes configuration"
      1. Ensure all valid mailboxes and aliases are added to the Mailboxes and Aliases tabs.
      2. On the Configuration tab:
        • Enable "Reject email to mailboxes not listed in the "Mailboxes" tab".
  • Alternatively, using LDAP or Microsoft 365 synchronisation tools, will populate the valid mailboxes and aliases list.
    • When the lists are populated, in conjunction with "Reject email to mailboxes not listed in the "Mailboxes" tab", This will ensure accurate billing.
  • Any other settings will cause mail to be accepted for ANY address confirmed as valid by the receiving server.
    • This "Catchall" behaviour is enabled by default on many servers/services.
    • This must be disabled to work with any external systems which validate mailbox addresses.
  • Mailboxes that have filtering disabled, are configured as an alias, or are marked as a distribution list or shared mailbox, will be excluded from billing.
  • We strongly recommend disabling any catch all functionality on all receiving mail servers