What does a bad IP reputation and good domain reputation mean on Google Postmaster?
Matthew Whittaker
Co-founder & CTO, Suped
Published 30 Jul 2025
Updated 14 Aug 2025
13 min read
Summary
When Google Postmaster Tools reports a bad IP reputation but a good domain reputation, it indicates a complex email deliverability scenario. The IP reputation pertains to the trustworthiness of the specific server (IP address) from which your emails are sent. A 'bad' score means Google views traffic from this IP as highly suspicious or spammy. Conversely, your domain reputation reflects the overall trust and credibility of your brand's domain name, which encompasses all sending sources and authentication practices. A 'good' domain reputation implies that your brand, broadly speaking, is seen as legitimate and not a source of spam.
Key findings
Distinct metrics: IP reputation and domain reputation are separate scores in Google Postmaster Tools. One can be poor while the other is strong, pointing to different underlying issues or strengths in your email program. IP reputation is more granular, focusing on the specific sending infrastructure, while domain reputation offers a broader view of your overall brand standing.
Impact on inbox placement: A bad IP reputation will likely lead to significant deliverability problems, with emails landing in the spam folder (or junk folder) for recipients on Gmail, Microsoft (Outlook/Hotmail), and Yahoo, even if your domain is well-regarded. The IP acts as a primary gatekeeper for incoming mail filtering. Mailgun notes that both IP and domain reputation are crucial, highlighting that your IP reputation dashboard is color-coded similar to your domain's, with red indicating 'bad' and green 'good'.
Dedicated IP concerns: If you are on a dedicated IP, a 'bad' IP reputation directly reflects issues with the email sent from that specific IP address, indicating that the sending behavior originating from it has been problematic.
Hidden delivery problems: Emails may appear 'successfully sent' from your sending platform, but low open and click rates, particularly for major freemail providers, are strong indicators that your messages are not reaching the inbox due to the poor IP reputation.
Key considerations
Investigate IP sending practices: Focus your efforts on the specific sending practices associated with the problematic IP address. This includes reviewing content, engagement, and complaint rates tied to that IP.
Strengthen authentication: Ensure that your SPF, DKIM, and DMARC records are correctly configured and aligned, as these foundational elements bolster your domain reputation and provide crucial trust signals to mailbox providers. Your domain's good reputation may be partly attributed to these being in order.
Optimize list hygiene: Verify your subscription methods. Implement confirmed opt-in (double opt-in) to ensure that only engaged and valid users receive your emails, minimizing complaints and bounces that can negatively affect IP reputation. This also prevents you from sending to bounce domains.
Monitor engagement metrics: Beyond Postmaster Tools, closely track your open rates, click-through rates, and complaint rates within your email service provider, especially for major ISPs. Low engagement signals can worsen your IP reputation over time.
Understand the interplay: Recognize that a strong domain reputation can provide some buffer, but it won't entirely counteract a consistently bad IP reputation. For insights into the relationship between these two, consider resources like Twilio's explanation of IP vs. domain reputation.
What email marketers say
Email marketers frequently encounter the challenging situation where their IP reputation is struggling, but their overall domain reputation remains intact. This often leads to confusion, as emails appear to be successfully sent by their systems, yet engagement metrics for key providers like Gmail and Microsoft indicate that messages are not reaching the inbox. Marketers emphasize the practical impact on campaigns and the need for deeper investigation into sending practices and list hygiene to diagnose and rectify the IP-specific issues without damaging the broader brand reputation.
Key opinions
Inbox placement struggles: Marketers observe that a bad IP reputation directly correlates with emails ending up in the spam folder, particularly for major freemail providers such as Gmail and Microsoft, impacting their ability to connect with subscribers.
Misleading 'sent' status: The email marketing platform might report emails as successfully sent, but a bad IP reputation means they are silently filtered into spam, leading to artificially inflated send rates and poor inboxing.
Engagement drop-off: A key indicator of IP reputation issues is a noticeable drop in open and click rates, specifically from recipients at Gmail, Microsoft, and Yahoo, even if non-freemail domains show stable engagement.
Opt-in quality matters: The way subscribers opt-in (e.g., through a signup form or terms and conditions) is seen as foundational to maintaining a healthy list and avoiding spam complaints that would hurt IP reputation.
Business context is key: Marketers acknowledge that understanding the specifics of their business and email program, such as the type of content (e.g., product listings for a newsletter), is essential for diagnosing reputation issues.
Key considerations
Verify true delivery: Don't solely rely on your email service provider's delivered status. Actively monitor open and click rates, especially for key ISPs, as a measure of true inbox placement.
Segment by ISP: Analyze your engagement data segmented by recipient domain (Gmail, Yahoo, Outlook, etc.) to pinpoint where the IP reputation is most affecting delivery. This can help you troubleshoot transactional emails effectively.
Review opt-in processes: Even with T&C agreements, consider implementing clearer, more explicit opt-in methods, such as confirmed opt-in, to reduce the chances of sending to uninterested or invalid addresses, which can lead to high spam complaint rates on your IP.
Align content with expectations: Ensure your newsletter content consistently matches subscriber expectations set during signup. Irrelevant or overly promotional content can increase spam complaints and hurt your IP reputation.
Leverage Postmaster Tools metrics: Regularly check Google Postmaster Tools for specific metrics like spam rate, IP reputation, and domain reputation. Understanding what metrics to monitor can help identify trends and issues early. SendLayer provides insights on improving domain reputation through Postmaster.
Marketer view
Marketer from Email Geeks explains that their CTO observed a challenging situation in Google Postmaster Tools, where the IP reputation score was bad, while the domain reputation remained good. This specific scenario highlights the complexity of sender reputation, where different components of their sending infrastructure are perceived differently by mailbox providers. They seek clarification on what this disparity indicates for their email program's overall health and deliverability performance, suggesting a need to understand the nuances of Postmaster data.Their primary concern is to decipher the implications of these mixed reputation scores, especially since their email newsletter, which primarily lists items for sale on their website, is a core communication channel. This situation underscores the importance of interpreting Postmaster data accurately to ensure that emails reach the inbox effectively.
14 Jul 2019 - Email Geeks
Marketer view
Marketer from Email Geeks notes that their email program operates on a dedicated IP address. This detail is crucial for diagnosing reputation issues, as a dedicated IP means the sender's own sending practices are directly responsible for its reputation, unlike shared IPs where other senders' actions can influence the score. Understanding this distinction is fundamental to addressing a bad IP reputation.This insight suggests that any negative reputation is a direct result of their own email sending patterns, content, or list hygiene. It points towards a need for a thorough internal audit of their email operations rather than attributing issues to external factors inherent in shared infrastructure.
14 Jul 2019 - Email Geeks
What the experts say
Email deliverability experts agree that the disparity between a bad IP reputation and a good domain reputation in Google Postmaster Tools is a critical, albeit common, diagnostic scenario. They emphasize that while domain reputation (which includes factors like DMARC, SPF, and DKIM alignment) speaks to the overall credibility of your brand, the IP reputation is often the direct gatekeeper for inbox placement at major Internet Service Providers (ISPs). A poor IP score, especially on a dedicated IP, signifies that the sending practices from that specific address are causing significant filtering issues, regardless of the domain's general trustworthiness. Experts advise a deep dive into the specific email program's dynamics to uncover the root cause of the IP's struggles.
Key opinions
IP as the primary filter: Experts confirm that a bad IP reputation almost certainly means mail will struggle to reach the inbox, particularly at Gmail. The IP is often the initial and most significant factor ISPs use to filter incoming email.
Domain's broader scope: Domain reputation reflects the aggregated trust across all email sent from that domain, regardless of the originating IP. It's a holistic view of the sender's identity and brand credibility.
Volatility of IP reputation: IP reputation can be more volatile and fluctuate more rapidly than domain reputation. This means a good IP can quickly turn bad if sending practices deteriorate, and vice versa.
Importance of context: To properly diagnose a bad IP with a good domain, experts require detailed information about the sending program, including business type, specific IP addresses, and opt-in methodologies.
SenderScore's role: Some experts mention Return Path's SenderScore as a widely used metric for IP reputation, indicating its broad influence across the email ecosystem.
Key considerations
Deep dive into program specifics: Gather comprehensive data on your email program, including your business model, the specific IPs and domains in use, and explicit details on how users opt-in to your mail. This holistic view is crucial for effective troubleshooting.
Prioritize IP health: Since IP reputation is often the most immediate determinant of inbox placement, focus efforts on ensuring consistent, high-quality sending from your IP, including proper IP warming for new IPs or those recovering from issues. Return Path offers guidance on how to warm up an IP address.
Monitor delivery metrics closely: Actively track your overall delivery rates and engagement (opens, clicks), especially at target ISPs. Low numbers here despite good domain reputation indicate a problem with the IP.
Implement strong authentication: Even with a good domain reputation, continuous verification of SPF, DKIM, and DMARC is crucial for reinforcing trust signals, which can indirectly aid IP reputation. Learn about advanced email authentication for more.
Utilize blocklist monitoring: Proactively check your IP address against various blocklists (or blacklists). Being listed on a significant blocklist is a clear indication of a compromised IP reputation and will severely impact deliverability.
Expert view
Expert from Email Geeks indicates that a bad IP reputation almost certainly implies that you will face significant problems delivering mail to Gmail. This statement underscores the direct and immediate impact of a poor IP score on inbox placement, highlighting Gmail's stringent filtering based on IP trustworthiness. It conveys that while other factors are at play, the IP serves as a primary gatekeeper for incoming mail, and a negative score here is a major red flag for deliverability.The expert further notes that a more comprehensive understanding requires knowing much more about the sender's mail program and any changes over time. This emphasizes that a bad IP is a symptom, not a diagnosis, and that a holistic review of sending behavior, volume, and recipient engagement is necessary to identify the root cause and implement effective solutions.
14 Jul 2019 - Email Geeks
Expert view
Expert from Email Geeks explains that domain reputation encompasses all mail originating from your domain, regardless of the specific IP address it's sent from. This highlights that the domain's standing is a comprehensive measure of trust, reflecting the overall credibility of your brand across various sending sources. It implies that a good domain reputation can be maintained even if one IP is struggling, indicating the resilience of the brand's identity.This insight is crucial for understanding why a bad IP can coexist with a good domain. While the IP addresses may be facing specific issues, the domain's overall health, often bolstered by strong authentication like DMARC, SPF, and DKIM, signals to ISPs that the brand itself is legitimate. This differentiation helps in segmenting troubleshooting efforts.
14 Jul 2019 - Email Geeks
What the documentation says
Official documentation from major email service providers, particularly Google Postmaster Tools, clarifies the meaning of IP and domain reputation scores and their impact on email delivery. These sources typically define a bad or low IP reputation as a clear indicator of high spam rates or problematic sending behavior originating from that IP address. Conversely, a good or high domain reputation signifies a consistent history of legitimate, desired mail, often underpinned by proper authentication. Documentation stresses that while distinct, both reputations are critical for successful inbox placement, and issues with one can significantly undermine the other, even if the domain is otherwise trusted.
Key findings
Google's reputation definitions: Google defines a BAD reputation as sending history showing a high rate of spam. A LOW reputation implies the domain or IP regularly sends a significant volume of spam. These definitions apply to both IP and domain reputations.
IP reputation's direct purpose: Documentation confirms that IP reputation is designed to assess the trustworthiness of the specific IP address from which emails are sent, acting as a primary filter to prevent spam and ensure the quality of incoming mailstreams.
Domain reputation's brand focus: Domain reputation, conversely, reflects the overall credibility of your brand's domain name. It’s a broader measure of trust, influenced by all sending activities associated with the domain and its authentication setup.
Interdependency of scores: While distinct, documentation often highlights that a poor IP reputation can undermine a strong domain reputation, and vice versa. ISPs consider both, and a severe issue in one area can significantly impact overall deliverability, even if the other is performing well.
Deliverability impact: Documentation consistently states that a poor IP or domain reputation directly leads to emails being flagged as spam or not reaching recipients' inboxes, severely affecting the success of email communications.
Key considerations
Adhere to sending guidelines: Strictly follow documented best practices for email sending, including maintaining clean lists, managing bounce rates, and responding to spam complaints, to prevent your IP from being associated with spammy behavior.
Prioritize authentication: Ensure proper implementation of SPF, DKIM, and DMARC. These authentication protocols are fundamental for building and maintaining a strong domain reputation and signaling legitimacy to receiving mail servers. For example, understanding the meaning of DMARC tags is essential.
Manage complaint rates: High spam complaint rates, explicitly cited in documentation as a cause of bad reputation, must be addressed swiftly. This often involves reviewing opt-in processes and content relevance. If you've had a spam incident, learn how to recover your reputation.
Gradual sending (IP warming): For new IP addresses or significant increases in sending volume, documentation often recommends a gradual increase in mail volume (IP warming). This helps build a positive sending history and avoids triggering spam filters that are suspicious of sudden, high-volume sending from unknown IPs. For detailed definitions of reputation levels, consult resources like Iterable's guide to Google Postmaster Tools.
Technical article
Documentation from Iterable outlines Google Postmaster Tools' reputation scores, explicitly stating that a BAD rating for either domain or IP means the sending history shows a high rate of spam. This provides a clear, official definition of what constitutes a severely compromised reputation in Google's eyes. It suggests that such a rating is not merely a warning but an indication of persistent, problematic sending behavior that directly violates anti-spam policies. It means immediate intervention is required.The documentation further clarifies that a LOW reputation means the domain or IP has the reputation to regularly send a significant volume of spam. This distinction indicates different levels of severity but consistently points to an association with spam, highlighting the importance of managing sending practices to avoid these detrimental classifications.
22 Mar 2025 - Iterable
Technical article
Documentation from MailMonitor explains that possessing a high IP reputation translates to a significantly higher probability that your messages will bypass the spam folder and instead reach the recipient's primary inbox. This emphasizes the direct influence of IP trustworthiness on successful email delivery outcomes. A strong IP score indicates to ISPs that the sending source is legitimate and reliable, allowing emails to be processed with less scrutiny.This highlights the importance for senders to prioritize practices that contribute to a positive IP reputation, such as maintaining engaged lists, avoiding spam complaints, and adhering to sending volume consistency. Ultimately, a high IP reputation serves as a crucial enabler for effective email communication, ensuring that messages have the best chance of being seen by their intended audience.
