Bounces

To receive a notification for each bounce message, turn on Forward Bounce Messages.

1. Open the Twilio SendGrid console.
2. Go to Settings > Mail Settings.
3. Click Forward Bounce Messages. The Forward Bounce Messages panel appears.
4. Choose which email address should receive the notifications.
5. Toggle Forward Bounce Messages Status to Enabled.
6. Click Save.

To change the range of bounces displayed in this list, choose a date range.

1. Open the Twilio SendGrid console.
2. Go to Suppressions > Bounces.
3. Click All Time. A calendar appears.
4. Click the date when your search should start.
5. Click the date when your search should end.

Your recipient list refreshes and displays the recipients bounced in that range.

To reset the date range to all time through the Twilio SendGrid console:

1. Click date range button. A calendar appears.
2. Click All Time.

Your recipient list refreshes and displays the recipients bounced for all time.

To download a list of bounces, export a comma-separated value list.

1. Open the Twilio SendGrid console.
2. Go to Suppressions > Bounces.
3. Click the gear icon.
4. Click Export CSV. The file downloads through your browser.

To remove a recipient from the bounce list, find the recipient and delete their entry from the list.

1. Open the Twilio SendGrid console.
2. Go to Suppressions > Bounces.
3. Choose if you want to delete certain bounces or all of them.
   • To delete all bounces:
     1. Click the gear icon.
     2. Click Delete All.
     3. When prompted, click Delete.
   • To delete some bounces:
     1. Select the checkbox next to the recipient name that you want to delete.
     2. Click Delete.
     3. When prompted, click Delete.

After you remove a recipient from the bounce list, Twilio allows you to send email to that recipient. The bounce list doesn't include unsubscribed recipients.

An asynchronous bounce occurs when Twilio SendGrid accepts a message for delivery, but that message reported as a bounce later. Asynchronous bounces are also known as "out-of-band" or "non-conversational" bounces. Consider any message that results in an asynchronous bounce as undeliverable. When this happens, a message might have both a delivery and a bounce event. This might result in anomalous campaign statistics.

With an asynchronous bounce, the email address that sent the original message receives a Delivery Status Notification (DSN) or Non-Delivery Report (NDR). These responses detail what made the message undeliverable. Senders might receive these responses minutes or hours after the recipient system accepted the message.

This behavior, unlike synchronous or "conversational" bounces, records the failure when the message transmits. With synchronous bounces, the remote inbox provider rejects the message during the initial delivery attempt and provides bounce codes. The code indicates the reason for the rejection. A delivery event doesn't occur with a synchronous bounce.

When asynchronous bounces occurs, events lack some contextual detail. This means the message ID and IP address might be unavailable.

Most bounces are synchronous and occur more often in corporate or small business domains. They might occur with greater frequency for business-to-business (B2B) senders. Most major inbox providers only generate synchronous bounces.

• Global Unsubscribes
• Group Unsubscribes