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 19 Aug 2025
9 min read
It can be perplexing to see a bad IP reputation displayed in Google Postmaster Tools, while your domain reputation remains good. This specific scenario highlights the nuanced way internet service providers (ISPs) assess incoming email, especially at services like Google. It suggests that while the overall health of your domain is strong, something specific to the sending IP address is causing concern. Understanding the distinction between these two reputation metrics is crucial for diagnosing and resolving deliverability issues.
A good domain reputation indicates that your brand, as identified by your domain, is generally trusted. This trust is built over time through consistent sending of legitimate, engaged email. Conversely, a bad IP reputation can act as a red flag, regardless of the domain's standing. It suggests that the specific server from which emails are originating has recently exhibited patterns associated with undesirable sending behavior, such as high spam complaints or sending to inactive addresses. This can lead to emails being filtered to the spam folder or rejected entirely, even if your domain itself is well-regarded.
The challenge here is that while your domain might be universally recognized as reputable, the particular IP address used for sending could be hitting internal blocklists (or blacklists) at services like Microsoft or Yahoo, preventing your emails from reaching the inbox. This situation is particularly critical for senders utilizing dedicated IP addresses, as the reputation of that single IP directly impacts their individual sending performance.
Understanding Google Postmaster Tools
Google Postmaster Tools is a free service that offers valuable insights into your email sending performance to Gmail users. It provides detailed dashboards including IP reputation and domain reputation scores, spam rates, feedback loops, and delivery errors. These scores are crucial because they directly influence whether your emails land in the inbox, go to spam, or are blocked entirely. A good reputation signals trustworthiness, while a bad reputation indicates a high likelihood of sending unwanted mail.
IP reputation, often measured on a scale from Bad to High, reflects the history and trustworthiness of the specific IP address used to send emails. If an IP address has a history of sending spam, hitting spam traps, or generating high user complaints, its reputation will plummet. This is particularly relevant for dedicated IPs, where your sending practices directly and solely influence that IP's standing. For more details on the differences, you can review our guide on IP versus domain reputation.
Domain reputation, on the other hand, is a broader indicator of your email program's health, tied to your sending domain. It encompasses factors beyond just one IP, including consistent authentication (SPF, DKIM, DMARC), overall engagement, unsubscribe rates, and user complaints across all IPs associated with your domain. A good domain reputation means your brand is recognized as a legitimate sender by ISPs, which is a powerful asset for deliverability. Google Postmaster Tools provides this view to help you understand your overall sender health.
Why the discrepancy on a dedicated IP?
When you observe a bad IP reputation alongside a good domain reputation on a dedicated IP, it points to a specific issue with how that particular IP address is being used or perceived. Since you're on a dedicated IP, its reputation is solely determined by your sending practices from that IP. This split suggests that while your overall sending strategy for the domain is sound, leading to a good domain reputation, there's a problem with the mail originating from that specific IP.
One common reason for this discrepancy is related to list acquisition or segmentation. If a specific segment of your audience, or a particular opt-in method, is leading to a higher rate of spam complaints or invalid addresses, it could disproportionately affect the IP used for those sends. Even if the majority of your emails are well-received, a concentrated pattern of negative engagement on a specific IP can trigger a bad IP score. IP reputation scores can be quite volatile.
Another factor could be insufficient IP warming, if this IP is relatively new or has seen a significant change in sending volume. Mailbox providers are cautious with new or significantly changed sending patterns to prevent spam. Without a gradual increase in volume and consistent positive engagement, a dedicated IP can quickly acquire a low or bad reputation. It's a bit like building credit, you need to prove trustworthiness over time. You might want to understand more about how IP reputation matters for deliverability.
The impact on email deliverability
While your domain's good reputation is a strong foundation, a bad IP reputation can severely undermine your email deliverability. Mailbox providers use both to make filtering decisions, and a low IP score can trump a good domain one for specific messages. This means emails sent from that problematic IP are highly likely to be directed to the spam folder or even rejected outright, impacting your reach to critical recipients at providers like Gmail, Microsoft, and Yahoo. This explains why you're seeing low open and click rates specifically for these major freemail providers, while non-freemail (e.g., corporate) addresses are unaffected; smaller corporate mail servers often have less stringent filtering.
The low engagement on major ISPs, despite successful sending, confirms that your emails are likely not reaching the inbox. This is a common symptom of a poor IP reputation where messages bypass initial rejections but are subsequently filtered into spam folders. The impact extends beyond just deliverability, affecting the effectiveness of your campaigns and the overall ROI of your email program.
Addressing the bad IP reputation is crucial. While a good domain reputation offers a layer of protection, it doesn't make an IP immune to poor performance. You'll need to identify the root cause of the IP's decline to restore full inbox placement. If you're experiencing a stuck bad reputation this indicates a persistent issue.
Steps to improve your IP reputation
To improve a bad IP reputation while maintaining a good domain reputation, you need a multi-pronged approach that focuses on the specific IP in question. Start by thoroughly reviewing your email sending practices associated with that IP. Look for any recent changes in volume, audience segments, or content that might have led to increased complaints or bounces.
Implementing a double opt-in process is a critical step for list hygiene. While accounts agreeing to terms and conditions is a form of opt-in, it doesn't verify the email address owner's intent to receive marketing messages. Double opt-in ensures that every subscriber explicitly confirms their interest, significantly reducing spam complaints and invalid email addresses that can harm your IP reputation. Regular list cleaning to remove inactive or bouncing addresses is also essential. This proactive measure helps prevent your IP from hitting spam traps or being associated with low-quality sending.
Analyze your email content for any elements that might trigger spam filters, such as excessive links, certain keywords, or poor HTML formatting. Monitor your DMARC reports closely, as they provide valuable insights into authentication failures and potential misuse of your domain that could inadvertently impact your IP reputation. Remember, improving a low IP reputation is a gradual process that requires consistent adherence to best practices and close monitoring of your metrics.
Here's a comparison of how different email providers might view your reputation:
Provider
IP Reputation Impact
Domain Reputation Impact
Recommendation
Gmail
Strongly considers IP. Bad IP often means spam folder, even with good domain.
High importance, but can be overshadowed by a poor IP score from a specific sender.
Focus on IP warming, engagement, and consistent sending patterns from dedicated IPs.
Outlook
Highly sensitive to IP reputation, quick to block (or blocklist) or junk based on sending history.
Significant weight. Strong domain reputation can help, but a bad IP can still lead to filtering.
Similar to Gmail, a problematic IP is a major deliverability hindrance.
Important for brand trust. A good domain helps recover from minor IP issues, but a bad IP is tough.
Ensure clean lists and strong authentication protocols (e.g., DMARC).
Views from the trenches
Best practices
Implement double opt-in for all new subscribers to verify consent and reduce invalid email addresses.
Regularly clean your email lists to remove inactive users, hard bounces, and known spam traps.
Segment your audience and tailor content to improve engagement, reducing complaints and unsubscribes.
Monitor your Google Postmaster Tools daily for both IP and domain reputation changes and respond quickly.
Ensure all email authentication (SPF, DKIM, DMARC) is correctly configured for your sending IPs and domain.
Common pitfalls
Sending to unengaged or old lists, which increases spam complaints and bounces, hurting IP reputation.
Not verifying email addresses at signup, leading to sending to invalid or hijacked accounts.
Ignoring Google Postmaster Tools warnings until deliverability issues become severe and widespread.
Focusing solely on domain reputation while neglecting the health of individual sending IPs.
Sending inconsistent volumes or types of email from a dedicated IP, which can be seen as suspicious.
Expert tips
If on a dedicated IP, isolate problematic sending streams to a different IP if possible, or pause them to clean up.
Analyze Postmaster Tools data alongside your internal email metrics (opens, clicks, unsubscribes, spam reports).
Consider engaging a deliverability expert to perform an audit of your email program and identify hidden issues.
Remember that IP warming is an ongoing process, not a one-time setup, and needs continuous nurturing.
A spike in
Expert view
Expert from Email Geeks says that a bad IP reputation suggests that you will have problems delivering mail to Gmail from that address. More details about the mail program and changes over time are needed to fully diagnose the issue.
2019-07-15 - Email Geeks
Marketer view
Marketer from Email Geeks says that their email newsletter contains a long list of items people want to sell on their website, with opt-in through signup forms and account terms and conditions.
2019-07-15 - Email Geeks
Wrapping up
The scenario of a bad IP reputation and good domain reputation in Google Postmaster Tools, particularly for senders using a dedicated IP, is a clear signal that specific sending practices from that IP are negatively impacting your deliverability to major mailbox providers. While your domain's overall trustworthiness is intact, the individual IP is being flagged, leading to emails landing in spam folders despite being successfully sent.
To resolve this, you must meticulously examine the traffic originating from the affected IP, focusing on audience engagement, list hygiene, and content quality. Implementing double opt-in, regularly cleaning your lists, and monitoring your DMARC reports for authentication issues are essential steps. By addressing the root causes of the IP's poor performance, you can gradually rebuild its reputation and ensure your valuable emails consistently reach the inbox.
Google. It suggests that while the overall health of your domain is strong, something specific to the sending IP address is causing concern. Understanding the distinction between these two reputation metrics is crucial for diagnosing and resolving deliverability issues. 
Microsoft or 
Yahoo, preventing your emails from reaching the inbox. This situation is particularly critical for senders utilizing dedicated IP addresses, as the reputation of that single IP directly impacts their individual sending performance.
Gmail, 
Microsoft, and Yahoo. This explains why you're seeing low open and click rates specifically for these major freemail providers, while non-freemail (e.g., corporate) addresses are unaffected; smaller corporate mail servers often have less stringent filtering.
Gmail
