How can you improve a bad domain reputation for email sending?
Michael Ko
Co-founder & CEO, Suped
Published 10 Jul 2025
Updated 17 Aug 2025
6 min read
A bad domain reputation can feel like an uphill battle, especially when your emails are consistently landing in spam folders or being outright blocked. It is a common challenge that many senders face, often stemming from issues like outdated email lists, low engagement, or poor sending practices. The good news is that recovering and improving your domain reputation for email sending is entirely possible, though it requires a systematic approach and patience.
Your domain's reputation is essentially a trust score assigned by mailbox providers (like Google, Microsoft, and Yahoo) based on your sending behavior. A poor score means your emails are less likely to reach the inbox, impacting your communication and business. Understanding the factors that influence this score is the first critical step toward recovery.
Identifying the root causes of a bad reputation
The first step in improving a bad domain reputation is to identify the root causes of the problem. This often involves a thorough analysis of your past sending behavior and subscriber acquisition methods. High spam complaint rates, low engagement, and sending to invalid addresses are common culprits that degrade your standing with mailbox providers.
Sometimes, issues arise from unintentional mistakes, such as migrating unsubscribed contacts during an ESP transition or using third-party opt-in services that collect low-quality leads. These practices can quickly lead to increased complaints and a damaged domain reputation. It's crucial to be honest about how subscribers were acquired and to address any historical missteps.
Once you pinpoint the reasons your emails are going to spam, you can start taking corrective actions. This assessment should cover everything from your email acquisition methods to your content and sending frequency. Without understanding the 'why,' any recovery efforts will be guesswork and unlikely to yield lasting results.
Common practices that harm reputation
Purchased lists: Sending to email addresses from bought or scraped lists. These contacts often have not opted in and are prone to marking your emails as spam, leading to high complaint rates.
Poor list hygiene: Not regularly removing inactive or invalid email addresses. This can result in bounces and spam trap hits, both damaging to reputation.
Sudden volume spikes: Drastically increasing your email sending volume without proper warming. Mailbox providers view sudden increases with suspicion.
Lack of clear consent: Not using double opt-in or failing to clearly communicate what subscribers will receive. This leads to higher unsubscribe and complaint rates.
Best practices for a healthy reputation
Permission-based lists: Only send to contacts who have explicitly opted in, preferably through a double opt-in process. This ensures genuine interest and reduces complaints.
Regular list cleaning: Implement a robust strategy for maintaining a clean email list, removing inactive users and bounced addresses to avoid spam traps.
Gradual warm-up: Increase sending volume gradually over time to build trust with internet service providers (ISPs) and avoid triggering filters.
Transparent opt-in: Clearly state what subscribers will receive upon signing up. This helps manage expectations and reduces future complaints.
Strengthening your technical foundations
Email authentication protocols are the bedrock of good domain reputation. Setting up SPF, DKIM, and DMARC properly demonstrates to mailbox providers that you are a legitimate sender and helps prevent email spoofing and phishing, which can severely damage your reputation.
SPF (Sender Policy Framework) specifies which IP addresses are authorized to send emails on behalf of your domain. DKIM (DomainKeys Identified Mail) adds a digital signature to your emails, allowing recipients to verify that the email was not altered in transit. DMARC (Domain-based Message Authentication, Reporting, and Conformance) builds on SPF and DKIM, providing instructions to receiving servers on how to handle emails that fail authentication and offering reporting on email authentication results. These protocols are essential for trust.
For domains with a bad reputation, implementing or correcting these records is a non-negotiable step towards recovery. Misconfigurations can sometimes be the hidden reason for poor deliverability, even if other sending practices seem sound. Regularly audit your DNS records to ensure they are correct and up-to-date. Here’s an example of a DMARC record you might implement:
Even with perfect content and list hygiene, without proper authentication, your emails are at a significant disadvantage. Mailbox providers rely heavily on these records to determine if an email is legitimate. A comprehensive guide to understanding domain reputation highlights the foundational role of authentication in this process.
Optimizing audience engagement and content quality
Once the technical aspects are in order, the next crucial step is focusing on your audience and the quality of your email content. Mailbox providers increasingly prioritize recipient engagement metrics. If subscribers are not opening your emails, clicking links, or are marking them as spam, it signals to ISPs that your emails are not valuable, further hurting your reputation. This is where active list management becomes paramount.
Cleaning up your email list means removing inactive subscribers who haven't opened or clicked your emails in a long time. These stale addresses can include spam traps which are detrimental to your sender score. Implementing double opt-in for new subscribers can also significantly improve list quality, as it ensures that only genuinely interested individuals are added to your list, reducing potential spam complaints.
Beyond list hygiene, review your email content to ensure it's relevant, valuable, and engaging to your audience. Personalized content, clear calls to action, and a consistent sending cadence can boost engagement and positively impact your reputation. Avoid sudden, large volume sends if your reputation is already low. Instead, warm up your sending gradually to rebuild trust.
Metric
Impact on reputation
Action to improve
Open rate
Low rates indicate disinterest, potentially leading to spam folder placement.
Improve subject lines and content relevance. Segment your audience.
Click-through rate (CTR)
High CTR signals engaging content, boosting positive sender signals.
Optimize content, personalize offers, and provide clear calls to action.
Spam complaint rate
High complaints severely damage reputation and can lead to blacklisting.
Ensure explicit consent, provide easy unsubscribe options, and clean your list regularly.
Unsubscribe rate
While not as bad as spam complaints, high rates suggest content misalignment.
Segment audiences, send relevant content, and manage subscriber expectations.
Monitoring and long-term maintenance
Consistent monitoring of your domain's reputation is key to preventing future declines and tracking your recovery progress. Tools like Google Postmaster Tools offer invaluable insights into your email performance with Gmail recipients, including spam rates, IP and domain reputation, and feedback loops. Additionally, regularly checking for any blocklist (or blacklist) listings is essential. Getting removed from these lists, if applicable, is a vital step in recovery.
Beyond active monitoring, it's beneficial to establish internal processes that support long-term email health. This includes regular audits of your subscriber acquisition forms, reviewing email content for spam trigger words, and ensuring your email sending platform is configured correctly. A proactive approach to email deliverability ensures that you are always aware of your domain's standing and can react quickly to any potential issues. Building a positive domain reputation is a continuous effort, not a one-time fix.
The time it takes to improve a bad domain reputation can vary significantly, often ranging from weeks to several months depending on the severity of the damage and the consistency of your corrective actions. Patience and persistence are key, as mailbox providers need to see consistent positive sending behavior over time to rebuild trust. Don't expect immediate results, but steady improvement will follow consistent good practices.
Views from the trenches
Best practices
Ensure proper email authentication with SPF, DKIM, and DMARC to prove sender legitimacy.
Implement a double opt-in process for all new subscribers to guarantee explicit consent.
Regularly clean your email list by removing inactive or unengaged subscribers.
Gradually increase email sending volume to warm up your domain and IP address.
Consistently monitor your domain reputation using tools like Google Postmaster Tools.
Common pitfalls
Sending emails to purchased, scraped, or unverified email lists.
Neglecting email list hygiene, leading to high bounce rates and spam trap hits.
Drastically increasing email sending volume, which can trigger spam filters.
Ignoring spam complaints and unsubscribe requests from recipients.
Failing to implement or correctly configure email authentication protocols (SPF, DKIM, DMARC).
Expert tips
Perform a thorough root cause analysis to understand why your domain's reputation declined.
Prioritize recipient engagement and send only mail that recipients genuinely want to receive.
If migrating ESPs, carefully review your unsubscribe lists to avoid mistakenly re-subscribing users.
Consider a temporary pause in sending for severely damaged reputations to allow a 'cool-down' period.
Focus on segmenting your audience and tailoring content to their preferences.
Expert view
Expert from Email Geeks says that fixing a bad domain reputation is entirely possible and is just a matter of time and applying the right techniques.
2024-03-05 - Email Geeks
Expert view
Expert from Email Geeks says that stopping the practices that caused the bad reputation is the first step, followed by identifying exactly what those 'bad things' were.
2024-03-05 - Email Geeks
Rebuilding trust and achieving inbox success
Recovering a bad domain reputation for email sending is a multi-faceted process that demands a commitment to best practices. It's about meticulously identifying what went wrong, shoring up your technical foundations with proper authentication, refining your audience management and content strategy, and vigilantly monitoring your progress. While it requires patience, the effort is well worth it for the long-term health of your email program.
By consistently applying these strategies, you can steadily improve your domain's standing, ensure your messages reach the inbox, and ultimately strengthen your overall email deliverability. Remember, a good reputation is earned through consistent, positive sending behavior.
Google, 
Microsoft, and 
Yahoo) based on your sending behavior. A poor score means your emails are less likely to reach the inbox, impacting your communication and business. Understanding the factors that influence this score is the first critical step toward recovery.
