What does SMTPBounceReason represent in Marketing Cloud data fields?

• A. The time the bounce occurred
• B. The recipient email address
• C. The reason for the bounce relayed by the mail system
• D. The bounce rate for the campaign

Answer: (C)

When a message bounces, SMTPBounceReason captures the diagnostic reason the receiving mail server reported for the bounce. It holds the exact reason relayed by the mail system, such as mailbox not found, user unknown, mailbox full, or a policy rejection. This helps you understand why delivery failed and how to triage or address issues, rather than just knowing that a bounce occurred. It’s not the time of the bounce, nor the recipient address itself, and it isn’t the campaign’s bounce rate (which is a summary metric). For example, a value like “550 5.1.1 recipient not found” tells you precisely what went wrong at the SMTP level.