One of the fundamentals of maintaining and improving your email deliverability is understanding how your email program performs. This is done by monitoring event-level metrics and watching for deviations and trends in performance over time. We also know that healthy engagement drives a strong, positive reputation. 

That’s why senders must look for ways to continue to drive positive results, like engagement, and decrease the negative ones, like bounces and blocks, by really understanding their email program as a whole.

One way to monitor your email deliverability is with our Deliverability Insights dashboard. However, if you want to consume granular event-level data along with the consumer data you are storing today, the best way to do so is by utilizing the data provided to you in the Twilio SendGrid Event Webhook as a Twilio SendGrid customer.

The Event Webhook allows you to use a data aggregator of your choice and notify a URL via HTTP POST with information about events that occur as Twilio SendGrid processes your email. You can use this data to:

  • Remove unsubscribes 
  • React to spam reports 
  • Determine unengaged recipients 
  • Identify bounced email addresses
  • Create advanced analytics of your email program

Since our webhook can be a powerful tool for our senders to understand their email performance, we are continuing to enhance this tool. Namely, we are now introducing a new event into the Event Webhook under Deliverability Metrics called Bounce & Block Classifications. You can now navigate to Settings > Mail Settings and turn on Bounce & Block Classifications to access this new event.

Bounce & Block Classifications help you simplify the actions you may need to take (or not) when you get a bounce-back response from an inbox provider. You can also find bounce classifications and comprehensive deliverability metrics in our Deliverability Insights product.

What are bounce classifications?

When an email bounces back, inbox providers inform senders of various deliverability issues that may be arising. Many of these responses will contain a Request for Comments (RFC) code and the reason for the bounce or block. A 5XX RFC code depicts hard bounces (permanent failures), while a 4XX RFC code depicts blocks.

However, not all inbox providers stick to this code, as each one can set and manage its own responses. These responses range from very helpful to sometimes confusing, which is why our Deliverability experts have done the work for you and classified many of these to help you make sense of bounce reasons.

Bounce classifications provided in the webhook are in 7 different categories: Content, Frequency or volume too high, Invalid address, Reputation, Mailbox unavailable, Technical, and Unclassified. You can read more about these specific events and how to take action on them here.

How to use bounce classifications

There are many ways to use bounce classifications, but here are a few scenarios to give you an idea: 

  • Scenario 1: You receive bounce classifications saying that your emails keep bouncing due to sending to an invalid address. This could mean it is time to send the recipient an in-app push notification to update their communication settings. 
  • Scenario 2: You start to get bounces back that indicate you have reputation issues applied to your sending. It may be time to clean up your sending to only those who have engaged recently, ensuring you are following sending best practices. By turning on bounce classifications and monitoring them over the next few weeks, you can understand the common bounce reasons for your sending. From there, adjust your sending around those common bounce reasons. 
  • Scenario 3: You get bounces and do not know what to change. Know that some bounces are inevitable, and not at all indicate that you need to change your sending. For instance, some technical blocks will indicate issues on the mail server side rather than with your sending. This would be a time to change nothing.

Improve your deliverability with Twilio SendGrid’s Event Webhook Bounce Classifications

The Event Webhook is one of the most useful tools to consume event-level data, allowing senders to monitor sending week over week, month over month. Use this data to customize your sending habits to how your recipients like to receive communication. After all, the better you customize your sending, the better it will be received by both the recipient and inbox providers. 

Access the Bounce & Block Classifications in the Deliverability Metrics section of the Event Webhook by logging into your Twilio SendGrid account today. Or, contact our Deliverability experts for help getting started.



Author
Sam has been with Twilio SendGrid since 2014 and, in that time, has worked closely with both our Compliance and Email Deliverability Services Teams. Sam currently brings that email knowledge to our Email Delivery Operations Team, where she likes to solve complex email problems. Outside of the office, you can find Sam hanging out with her three dogs and reading a good book.
Ayanna Julien
Reviewer
As Twilio SendGrid's Editorial Marketing Manager, Ayanna owns the quality assurance of blog content by focusing on authentic storytelling and editorial integrity. When not editing, Ayanna enjoys reading a good fiction novel or writing her own fiction.