Did you know that your sending domain carries a reputation just like your IP address does? It’s true. Domain reputation is becoming a more and more important part of how mailbox providers decide whether or not your email lands in the spam folder, or the inbox. What does this mean for senders? You might already know that it’s a good idea to send your marketing email from different IPs than your transactional email. This will always be a best practice. However, if mailbox providers are assigning a reputation to your domain, does that dilute the effectiveness of IP segmentation? To some extent it does. If your marketing email generates enough negative feedback from recipients, and it is being sent from the same domain as your transactional emails, it can actually impact your ability to get your transactional messages delivered. Without getting too technical, it’s important to know that your sending domain appears in several places in your message headers (specifically the ReturnPath and the DKIM d= field). This means that simply changing the domain in the From address is not enough to keep the reputations of the two email streams segmented; you need to actually change the domain with which you are signing the messages. What can you do about it? So, you need your two different types of mail sent from two different domains and you also need to have the message headers populated accordingly. Piece of cake. Using the SendGrid whitelabel tool, there is an easy way to accomplish this. All you need to do is whitelabel and validate two different sending domains. For example, email.transactional.mybusiness.com and email.marketing.mybusiness.com. With these two validated whitelabels in place on your SendGrid account, any message sent from firstname.lastname@example.org will be have a ReturnPath of “email.transactional.mybusiness.com” and the DKIM d= will read “transactional.mybusiness.com”. Similarly, messages sent from email@example.com will have a ReturnPath of “email.marketing.mybusiness.com” and the DKIM d= will read “marketing.mybusiness.com”. Why is this important? Mailbox providers desperately want all true transactional mail to be delivered with no hiccups. If a sender is having problems with receipts or order confirmations being filtered, most mailbox providers are quick to fix the issue. However, if your newsletters are suffering from poor inboxing, they will rarely treat the issue with the same urgency. The takeaway is that properly segmenting your transactional traffic by IP and domain, protects your important mail from potential reputation issues, and it makes it easier for mailbox providers to mitigate deliverability issues when they come up. For more information on domain and IP reputation, check out our guide, The ABCs of ISPs.