Following are the settings that can be specified in the filters section of the X-SMTPAPI header. All filters and setting names must be lowercase.

  • If you’re enabling a Setting, also called a filter, via SMTPAPI, you are required to define all of the parameters for that Setting.
  • Setting enabled status will always default to your settings on the website, unless otherwise defined in your X-SMTPAPI header
  • If you enable a disabled setting, our system will not pull your settings for the disabled setting. You will need to define the settings in your X-SMTPAPI header Example: If you have a footer designed but disabled, you can’t just enable it via the API; you need to define the footer in the API call itself.
  • All filter names and setting names must be lowercase.

For more information on the utility of these settings, please check out the Settings section.

Some Settings are not listed here, because they cannot be defined on a per-message basis. To update these other Settings, please refer to the Web API Filter Settings commands.

Filter: bcc

Sends a BCC copy of the email created in this transaction to the address specified.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting
email email email address destination for the bcc message
1
2
3
4
5
6
7
8
9
10
{
  "filters" : {
    "bcc" : {
      "settings" : {
        "enable" : 1,
        "email" : "you@example.com"
      }
    }
  }
}

Filter: bypass_list_management

This setting is very powerful, and can only be used on a per-message basis. Use with extreme caution.

Some emails are too important to do normal list management checks, such as password resets or critical alerts. Enabling this filter will bypass the normal unsubscribe / bounce / spam report checks and queue the email for delivery.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting
1
2
3
4
5
6
7
8
9
{
  "filters" : {
    "bypass_list_management" : {
      "settings" : {
        "enable" : 1
      }
    }
  }
}

Filter: clicktrack

Rewrites links in email text and html bodies to go through our webservers, allowing for tracking when a link is clicked on.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
{
  "filters" : {
    "clicktrack" : {
      "settings" : {
        "enable" : 1
      }
    }
  }
}

Filter: dkim

Allows you to specify the domain to use to sign messages with DKIM certification. This domain should match the domain in the From address of your email.

Parameter Name Parameter Value Parameter Description
domain domain The domain you would like your DKIM certification signed with
use_from 0 | 1 If enabled, the domain in the From: header of the email will be used to sign your DKIM

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
10
{
  "filters" : {
    "dkim" : {
      "settings" : {
        "domain" : "example.com",
        "use_from" : false
      }
    }
  }
}

Filter: footer

Inserts a footer at the bottom of the text and HTML bodies.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting
text/html string String containing html body
text/plain string String containing text body

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
10
11
{
  "filters" : {
    "footer" : {
      "settings" : {
        "enable" : 1,
        "text/html" : "<p>Thanks,<br />The SendGrid Team<p>",
        "text/plain" : "Thanks,\n The SendGrid Team"
      }
    }
  }
}

Filter: ganalytics

Re-writes links to integrate with Google Analytics.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting
utm_source string Value for the utm_source field
utm_medium string Value for the utm_medium field
utm_term string Value for the utm_term field
utm_content string Value for the utm_content field
utm_campaign string Value for the utm_campaign field

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
10
11
12
13
{
  "filters" : {
    "ganalytics" : {
      "settings" : {
        "enable" : 1,
        "utm_source" : "Transactional Email",
        "utm_medium" : "email",
        "utm_content" : "Reset Your Password",
        "utm_campaign" : "Redesigned Transactional Messaging"
      }
    }
  }
}

Filter: gravatar

Inserts an img tag at the bottom of the html section of an email to display the gravatar associated with the mail sender.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
{
  "filters" : {
    "gravatar" : {
      "settings" : {
      "enable" : 1
      }
    }
  }
}

Filter: opentrack

If you don’t use ‘replace’ this will insert an <img> tag at the bottom of the html section of an email which will be used to track if an email is opened. If you choose to use ‘replace’, you can put the tracking pixel wherever you would like in the email and SendGrid will replace it at send time.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting
replace string A string to be replaced by SendGrid with the tracking image at send time.

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
10
{
  "filters" : {
    "opentrack" : {
      "settings" : {
        "enable" : 1,
        "replace" : "%opentrack%"
      }
    }
  }
}

Filter: spamcheck

Tests message with SpamAssassin to determine if it is spam, and drop it if it is.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting
maxscore 1 to 10.0 Score after which the message will be dropped (default is 5.0, higher scores indicate higher likelihood of spam)
url url an optional url to POST the email and a copy of the report to. Refer to the Spam Checker documentation for POST details.

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
10
11
{
  "filters" : {
    "spamcheck" : {
      "settings" : {
        "enable" : 1,
        "maxscore" : 3.5,
        "url" : "http://example.com/compliance"
      }
    }
  }
}

Filter: subscriptiontrack

Inserts a subscription management link at the bottom of the text and html bodies or insert the link anywhere in the email.

If you wish to append an unsubscription link, use the text/html and text/plain paremeters. However, if you wish to have the link replace a tag (such as [unsubscribe]), use the replace parameter.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this App
text/html string HTML to be appended to the email, with the subscription tracking link. You may control where the link is by using a tag like so: <% link text %>
text/plain string Text to be appended to the email, with the subscription tracking link. You may control where the link is by using a tag like so: <% %>
replace string A tag that will be replaced with the unsubscribe URL (e.g. [unsubscribe_url]). If this parameter is included, it will override text/html and text/plain The URL of the link will be placed at the replace tag’s location, with no html or other formatting.

The landing argument cannot be used in SMTPAPI. It can only be setup via the UI or WebAPI, as an account-level setting.

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
10
11
{
    "filters": {
        "subscriptiontrack": {
            "settings": {
                "text/html": "If you would like to unsubscribe and stop receiving these emails <% click here %>.",
                "text/plain": "If you would like to unsubscribe and stop receiving these emails click here: <% %>.",
                "enable": 1
            }
        }
    }
}

Filter: templates

This setting refers to SendGrid’s transactional templates. SendGrid supports versioning, and the ability to create multiple transactional templates. Previously, we had a Template App, which is now referred to as the Legacy Template App.

Uses a transactional template when sending an email. More information on using transactional templates with the SMTP API may be found in the transactional templates API Reference.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting
template_id string The ID of the template to use when sending a message, represented by a string.

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
10
{
  "filters": {
    "templates": {
      "settings": {
        "enable": 1,
        "template_id": "5997fcf6-2b9f-484d-acd5-7e9a99f0dc1f"
      }
    }
  }
}

Filter: template

This setting refers to our original Email Template app. We now support more fully featured transactional templates. You may create multiple transactional templates that allow for versioning, in addition to several other features.

Wraps a template around your email content. Useful for sending out marketing email and other nicely formatted messages.

Parameter Name Parameter Value Parameter Description
enable 0 | 1 Disable or enable this Setting
text/html string String containing html content for the template (must contain a <% body %> tag)

Example X-SMTPAPI Header Value

1
2
3
4
5
6
7
8
9
10
{
  "filters" : {
    "template" : {
      "settings" : {
        "enable" : 1,
        "text/html" : "<html><head></head><body bgcolor='pink'><div style='width:200px' bgcolor='#FFF'><% body %></div></body></html>"
      }
    }
  }
}