What is the threshold for bounces after which my reputation is affected?
There is no specific threshold for bounces. Ideally, most email senders can achieve delivery rates of 98-99%, which is also the case with most MoEngage customers.
High bounce rates can be due to hard bounces caused by invalid email addresses. This indicates poor email list quality, and over time, it can negatively impact reputation, particularly if the rate of hard bounces exceeds 1% per day.
Is there a possibility that MoEngage and Email Service Provider (SendGrid, Amazon SES) dashboards indicate an email is delivered even if the intended recipient does not receive it?
Yes, emails get marked as Delivered once the recipient email server accepts the request to deliver the email. It is possible that mail clients (gmail, yahoo etc.) may not deliver the email to the recipient even after sending the delivery callback to ESPs (SendGrid, Amazon SES). In such cases, details related to delivery can only be established by reaching out to the mail client in question.
Are there rules to be maintained to reduce the hard bounce rate?
No explicit or exact rules must be maintained to reduce the hard bounce rate. But if you experience a daily hard bounce rate of 10%, this significantly impacts your reputation much sooner than a daily hard bounce rate of 1%.
Double-opt-in, welcome, and sign-up campaigns typically encounter high hard bounce rates, such as 3–5% daily, without significant issues. This is expected when you send the first email to a new customer.
What causes soft bounces?
Soft bounces occur due to poor list quality and reputation issues, such as a full mailbox, unreachable smaller domains, or IP blocks. You must suppress soft bounces that occur repeatedly but are not a result of IP or domain blocks.
How does soft bounce affect my reputation?
A sender with below-average email list quality often experiences frequent blocks. Ultimately, reputation is affected by your audience's quality and your sending behavior.
You must aim for a 99% delivery rate, excluding the sign-up/welcome campaigns. You must also have a sign-up or welcome campaign that cleans any new audiences added to your database. Monitor and request email removal from the database or mailing list whenever an IP/domain block occurs.
Does MoEngage support email address validation?
Currently, MoEngage does not have in-house support for this and is yet to partner with third-party email validation vendors. If you wish to clean your email list using a third-party email validation tool, you must manage it independently. Some examples of such tools include Email List Verify, NeverBounce, ZeroBounce, Kleanmail, Verifybee, and BriteVerify.
Note that Sendgrid offers email list validation.
Can we send emails to the purchased lists?
No, you cannot send emails to the purchased list. Sending emails to users who have not expressed consent can impact delivery and deliverability. Most countries also have strict mailing and privacy laws, which make sending without consent a punishable offense.
Can we send emails to cold users?
MoEngage does not recommend sending emails to cold users.
Depending on the country (GDPR mandates the deletion of user accounts and data after 18 months of inactivity) and without legal restrictions, cold users can be targeted carefully. However, it is advisable to approach this strategy in smaller volumes and mitigate any potential impact on deliverability over an extended period. You must consult with your email deliverability consultant to develop a plan accordingly.
What is throttling?
Throttling is a method of slowing down the speed at which emails are sent, ensuring a consistent pace per minute rather than delivering the entire volume at once. If throttling measures are not implemented, MoEngage attempts to send emails rapidly. Use Request Per Minute (RPM) to throttle your campaigns and send them steadily. For more information, refer to Throttling.
How does campaign throttling help?
Throttling contributes to improved email delivery. By default, most systems are designed to send emails at once. For instance, if you send a batch of 1 million emails, MoEngage attempts to deliver them all simultaneously. However, this approach can lead to problems like rate-limiting imposed by ISPs, resulting in delivery delays, minor IP blocks, or even temporary blocks due to rate limitations. In some cases, higher rate-limiting and subsequent retries may be interpreted by ISPs as Namespace Mining behavior, potentially resulting in a significant IP block.
However, by implementing throttling at a rate of, let's say, 10K RPM (emails per minute), the 1 million emails can be sent steadily over an hour and a half, thereby avoiding the issues mentioned above. Throttling all campaigns is considered a best practice. Depending on the client, volume, and system stability, the throttling rate can gradually increase as the volume increases.
Throttling is crucial for new senders, as ISPs (such as Yahoo) tend to impose volume rate limits on new IP addresses. Implementing throttling from MoEngage helps facilitate a faster warming-up and minimizes Yahoo issues.