Hard and Soft Bounce Definitions | Print |
Written by Pedro Martins   
Monday, 02 June 2008 12:18


Hard Bounce definition:

A delivery status message stating that the email could not be delivered to the address. A permanent fatal error message, which is sometimes called a perm fail.

Common Reasons for getting a hard bounce:

  • User does not exist for the given domain (e.g. there is no user named bob at example.com)
  • The domain does not exist (the domain nonexistantdomain.com doesn't exist)

    • What to do with Hard Bounces: Hard bounces should be removed from your mailing list and database / CRM system, they are addresses that may have once worked but do not work anymore. Failure to remove hard bounces can have negative effects on your deliverability.

    Soft Bounce definition:

    A delivery status message stating that the email could not be delivered to the address for a temporary reason. A temporary error message some times called a temp fail.

    Common Reasons for getting soft bounces:

  • The user's mail box is full, exceeded the quota
  • The mail server is too busy

    • What to do with Soft Bounces: Soft bounces should be monitored, if an address is consistently soft bouncing you may want to remove it from your list after a few consecutive soft bounces.