Sender reputation is a score that email service providers use to evaluate how trustworthy a sender’s domain and IP address are. This score is shaped by a combination of factors, including spam complaints, bounce rates, authentication setup, sending volume, and overall engagement with previous emails.
A strong sender reputation increases the likelihood that messages will reach the inbox, while a weak one can lead to filtering, throttling, or placement in the spam folder.
Maintaining a healthy reputation relies on clean lists, consistent sending patterns, relevant content, and strong subscriber engagement. Practices such as double opt-in and proper list hygiene contribute to building domain trust over time.