Why is my IP classified as very high volume by Return Path if I send low volumes?

Return Path (now Validity) aggregates data from various sources. If your IP is shared, its classification reflects the total volume from all senders using that IP, not just yours. Additionally, if the IP has a history of high-volume sending before you used it, that history can persist.

What causes my sender score to dip with low email volume?

A dipping sender score despite low volume is often due to poor sending quality rather than quantity. Factors include high bounce rates, spam complaints, low recipient engagement (opens, clicks), or hitting spam traps. Mailbox providers assess your behavior to determine your reputation.

How can I improve my sender score and volume classification?

Start by regularly cleaning your email list to remove invalid or unengaged addresses. Ensure your email authentication (SPF, DKIM, DMARC) is correctly configured. Monitor engagement metrics closely and adjust your content strategy. If on a shared IP, consider a dedicated IP if volume justifies it, or discuss options with your ESP.

Can I change Return Path's volume classification for my IP?

While you can't directly change Return Path's historical data for a shared IP, improving your sending practices (list hygiene, engagement, authentication) will positively influence your overall reputation. Over time, consistent good behavior can improve the perceived quality of the IP, even if its volume classification remains high due to collective usage.

Why is my IP classified as very high volume by Return Path, and my sender score dipping? - Sender reputation - Email deliverability - Knowledge base

It can be incredibly perplexing when you're diligently managing your email sending, maintaining relatively low volumes of a few thousand emails daily, yet Return Path classifies your IP as a "very high volume" sender. This often comes hand-in-hand with a disheartening dip in your sender score, leaving you wondering what's truly happening behind the scenes.

The discrepancy between your actual sending volume and Return Path's classification is a common point of confusion for many email marketers. This classification, along with a declining sender score, signals a deeper issue with how your IP's reputation is being perceived by mailbox providers.

Understanding why this happens is crucial for diagnosing and resolving deliverability challenges. It's not always about the number of emails you send, but rather a combination of factors that contribute to an IP's perceived volume and overall reputation.

Understanding Return Path's volume classification

Return Path (now part of Validity) is a major player in email reputation, providing services like Sender Score. This service rates the reputation of outgoing mail server IP addresses on a scale from 0-100. Their algorithms analyze billions of email messages daily to assess IP and domain reputation.

The primary reason your IP might be classified as very high volume, despite your low sending, often comes down to whether you're using a shared IP address. If your emails are sent from an IP shared with other senders, Return Path's system aggregates the volume from all entities using that IP. Even if your individual volume is low, the collective volume from all shared users could be substantial, leading to a "very high volume" classification for the IP as a whole. This is a common scenario, especially if you're using an Email Service Provider (ESP).

Another potential factor is the prior history of your IP. If you've recently acquired or started using an IP address, its past usage can heavily influence its current classification. An IP that was previously used by a high-volume sender, or perhaps even by a spammer, will retain that historical context for some time, affecting its perceived volume and reputation, even if your current sending patterns are exemplary. This can sometimes lead to Return Path showing inaccurate data or low scores. You might find more information on this topic in our guide on why SenderScore reports inaccurate data.

The classification is less about your specific sending volume and more about the historical data and collective activity tied to that IP. It's important to differentiate between your sending practices and the broader reputation of the IP itself.

Why your sender score dips

A dipping sender score, especially when your volume is low and warm-up is slow, points to underlying reputation issues beyond just volume. While volume contributes, it's the quality of that volume that truly matters. A low sender score can significantly impact your email deliverability.

One of the most impactful factors is poor recipient engagement. If your emails are consistently ignored, deleted without opening, or worse, marked as spam, it sends negative signals to mailbox providers. This behavior suggests your content isn't relevant or desired by recipients, even if your list is technically valid.

Another critical element is sending to invalid or low-quality email addresses. High bounce rates, especially hard bounces, are red flags. Mailbox providers interpret a high bounce rate as a sign that you might be a spammer, as legitimate senders typically maintain clean lists. Moreover, hitting spam traps, which are dormant email addresses used to identify spammers, can severely damage your IP's reputation and lead to immediate blacklisting (or blocklisting).

Spam complaints are perhaps the most damaging signal. Even a small number of direct spam complaints can disproportionately affect your sender score, as these are strong indicators of unwanted mail. Different ISPs weigh complaints differently; for example, a complaint at Cloudmark may have a more significant impact than one at Gmail. Our guide on why your sender score has dropped delves into this further.

Strategies to improve your sender score

Improving your sender score and navigating volume classifications requires a multi-faceted approach, focusing on list hygiene, content quality, and proper authentication. Here are some key strategies:

Maintain a clean list: Regularly remove inactive or unengaged subscribers. Implement a double opt-in process to ensure all subscribers genuinely want your emails. This helps reduce bounce rates and spam trap hits. Poor IP reputation can lead to poor domain reputation.
Monitor engagement: Track open rates, click-through rates, and unsubscribe rates. Low engagement can be a sign that your content isn't resonating with your audience.
Implement authentication: Ensure your SPF, DKIM, and DMARC records are correctly configured. These authentication protocols verify that your emails are legitimate and haven't been tampered with, which is crucial for building trust with mailbox providers. Learn more about DMARC, SPF, and DKIM.
Warm up new IPs carefully: If you're using a new IP, even a shared one, gradually increase your sending volume to build a positive reputation. Rapid increases can trigger spam filters and lead to a blocklist (or blacklist) listing.

Consider migrating to a dedicated IP if your volume justifies it. While it may not solve the immediate "very high volume" classification from Return Path if you're on a shared IP with previous high usage, a dedicated IP gives you full control over its reputation. This is especially beneficial for high-volume senders, as it allows you to spread out sending across multiple IPs and build a reputation based solely on your practices.

Shared IP challenges

When using a shared IP, your reputation is tied to other senders using the same address. Their sending practices, good or bad, directly impact your deliverability. If other users send spam or have poor list hygiene, your IP's overall score can suffer, regardless of your actions.

Monitoring

It can be difficult to pinpoint the exact cause of a reputation dip on a shared IP, as you lack visibility into the other senders' practices. This makes troubleshooting more complex and recovery slower. Monitoring your sender score and blocklists is key to understanding your standing.

If you suspect your current ESP's shared IP strategy is causing issues, consider discussing a dedicated IP option or exploring other ESPs known for their strong reputation management. Some ESPs provide different levels of IP allocation based on volume and reputation needs. Our article on IP strategy for low volume senders offers more insights.

Views from the trenches

Best practices

Actively monitor your sender score and blocklist status to catch issues early.

Regularly clean your email lists by removing inactive or unengaged subscribers.

Implement double opt-in for all new subscribers to ensure high quality leads.

Segment your audience and tailor content to improve engagement rates.

Ensure proper SPF, DKIM, and DMARC authentication for all outgoing emails.

Common pitfalls

Ignoring a dipping sender score, assuming it will resolve itself over time.

Sending emails to purchased or old, unverified lists, which can contain spam traps.

Not configuring email authentication protocols, leading to trust issues with ISPs.

Failing to warm up new IP addresses or significantly increasing volume too quickly.

Relying solely on volume metrics without considering engagement and bounce rates.

Expert tips

Focus on the full spectrum of signals that influence reputation, not just volume.

Engage with postmaster tools from major mailbox providers like Gmail and Outlook.

Understand that different ISPs weigh reputation factors with varying importance.

Consider a dedicated IP if shared IP issues persist despite good sending practices.

Automate bounce processing and complaint feedback loop subscriptions.

Marketer view

Marketer from Email Geeks says a new IP might have been used heavily by someone else before, which explains why Return Path classifies it as high-volume.

2019-11-05 - Email Geeks

Marketer view

Marketer from Email Geeks says that a sender score receives feedback from some ISPs and then compiles the result, assuming consistent behavior across all ISPs, so a spam complaint at Cloudmark will affect it more than at Gmail.

2019-11-05 - Email Geeks

Navigating your email sending reputation

Dealing with a "very high volume" classification from Return Path and a dipping sender score, especially when your actual sending volume is low, can be frustrating. The key takeaway is that these metrics reflect more than just your current sending volume.

It often points to the shared nature or historical baggage of your IP, coupled with critical reputation factors like engagement, bounce rates, and spam complaints. A comprehensive approach that prioritizes list hygiene, strong email authentication, and consistent monitoring is essential for sustained deliverability.

By understanding these nuances and implementing best practices, you can effectively manage your email program, improve your sender reputation, and ensure your messages consistently reach the inbox. Continuous vigilance and adaptation to evolving email ecosystem requirements are critical for long-term success. Further insights can be found in our guide on troubleshooting a dropping sender score.