IP reputation refers to the trustworthiness score assigned to an IP address based on its email-sending behavior. Internet service providers (ISPs) and spam filters use IP reputation to decide whether emails from that address should be delivered to the inbox, the spam folder, or blocked entirely.
IP reputation is a measure of how email recipients and filtering systems perceive the quality of email traffic coming from a specific IP address. Factors that influence IP reputation include:
A high IP reputation means your emails are more likely to land in the inbox, while a poor IP reputation can result in deliverability problems or complete blocking by ISPs.
ISPs and anti-spam systems evaluate several data points when assigning an IP reputation score:
Reputation data is aggregated by ISPs, mailbox providers, and third-party monitoring services, such as Microsoft SNDS or Google Postmaster Tools.
IP reputation is critical because it:
Without a good IP reputation, even well-designed emails with great content may fail to reach the intended audience.
IP reputation monitoring and management are essential for:
Example scenario: An e-commerce business experiences a drop in engagement and discovers its IP address is on a spam blacklist due to a compromised sending account. Restoring IP reputation becomes a priority to regain inbox placement.
You can use tools like Google Postmaster Tools, Microsoft SNDS, or third-party services such as Talos or SenderScore.
High spam complaints, sending to invalid email addresses, failing authentication checks, and poor list hygiene are common causes.
Yes. It requires stopping harmful sending practices, improving list quality, authenticating your domain, and sometimes warming up the IP again.
