Creating a Custom Bounce Domain

You can improve your deliverability and email branding by adding a custom bounce domain. A custom bounce domain provides another layer to the branding that some ISPs care about.
Note: Only one custom bounce domain is permitted per account at this time.
By adding a bounce domain to your account, you can customize the address that is used for the Return-Path header (which denotes the destination for out-of-band bounces). This custom bounce domain overrides the default Return-Path (also known as the envelope FROM) value of "" for all messages sent.
To configure a custom bounce domain, choose the subdomain you would like to use (e.g. and add the following CNAME record to your DNS settings:
Name Type Data CNAME

This DNS record will ensure that out-of-band/asynchronous bounces to be routed to SparkPost for processing.
Once you have configured your DNS settings, configure custom bounce domains through the SparkPost user interface, follow the steps below:
  1. Select Account and then Bounce Domains from the main menu.
  2. Click the New Domain button to add a new bounce domain.
  3. Add bounce domain
  4. Select test
  5. Make sure the domain is verified by the green check mark
Bounce domains can also be managed by API. Make sure to use the verify endpoint when using API.