Email Headers

In the fight against SPAM, ISPs and email providers like Gmail and Outlook are increasingly using special information in email headers to manage unsubscribes and to help their systems decide if the incoming email is legitimate.

What are Email Headers?

For some context, an email consists of three core elements: 1) the envelope, 2) the header(s), and 3) the body of the email message. Think of the envelope as the wrapper that allows the email to be sent from A to B. The body is the bit we all normally see (the words and images), while the header is generally hidden but essential for email delivery.

Some headers are mandatory and you will already be familiar with them, such as the FROM, TO and DATE headers. Others are optional, but very commonly used, such as SUBJECT and CC. Other headers include the sending time stamps and the receiving time stamps of all mail transfer agents that have received and sent the message.

arpReach allows you to create any number of custom email headers in addition to the mandatory ones already used and assign them to any of your sending email systems.

As ISP requirements change, we occasionally add some custom headers as defaults, meaning they are automatically created when you install arpReach.

List-Unsubscribe is one such default custom email header and it inserts a Manage Subscriptions link into the header of emails as required by some ISPs.

You can add new custom email headers as ISPs start to use them. You can use the personalization tags in arpReach to construct the link format and insert the correct information for the recipient contact. This is helpful if you need to track who an email was sent to if the recipient complains.

At an advanced level, the real benefits of tracking custom X-Headers within email metrics begin when you separate campaigns, regions, or other special information to create new email metrics. With this new information, you will be able to determine and then optimize which campaign or region is providing the most opens or clicks. You will also be able to quickly repeat your tests to help increase conversions.

Managing Your Custom Email Headers

To manage your custom email headers, choose Setup / Email Headers / Show List from the menu bar:

To add a new custom email header, choose Setup / Email Headers / Create New from the menu bar:

… or choose Create a header from the I want to… menu on the Custom Email Headers list screen:

To edit an existing custom email header, choose Edit from the actions column on the Custom Email Headers list screen:

When creating or editing a custom email header, the settings are the same.

  • Header – the email header. For example, X-MyHeader.
  • Value – the value of the email header. You can use the personalization tags in arpReach such as {MANAGE_LINK}.
  • Assign to new email systems – check this box to automatically assign the custom email header to new email systems that you add. This can be changed in the settings of each email system.
  • Assign to these email systems – check the email systems that you want to assign the custom email header to. This can be changed in the settings of each email system.