Is the Charter.net feedback loop still functional?
Matthew Whittaker
Co-founder & CTO, Suped
Published 9 May 2025
Updated 18 Aug 2025
7 min read
Many email senders frequently ask about the status of the Charter.net feedback loop (FBL). For those relying on these vital tools to manage sender reputation and ensure email deliverability, understanding which Internet Service Providers (ISPs) offer feedback loops is crucial. Historically, Charter, now part of Spectrum Communications, did have a feedback loop, but its functionality has changed significantly over time, particularly as Spectrum has evolved its email services.
A feedback loop is a mechanism where an ISP notifies a sender when one of their subscribers marks an email as spam or junk. This notification is critical because it allows senders to identify and remove disengaged or complaining recipients from their mailing lists, thereby maintaining a healthy sender reputation and avoiding email blocklists (or blacklists). Without this direct channel of communication, senders are often left guessing why their emails are not reaching the inbox.
Unfortunately, the direct answer to whether the Charter.net (Spectrum) feedback loop is still functional for external senders is generally no. Public information and community discussions indicate that the formal Charter feedback loop has been discontinued or is no longer accessible for external senders, especially as Spectrum has increasingly moved away from providing residential email services to its customers. This shift has important implications for email marketers and bulk senders targeting Spectrum recipients.
The evolution of Spectrum email services
Charter Communications, which operated the charter.net domain, merged with Time Warner Cable and Bright House Networks to form Spectrum. This consolidation brought significant changes to their service offerings, including email. Over time, Spectrum has gradually phased out or deprioritized email services for residential customers, encouraging them to use third-party email providers like Gmail or Outlook.
This shift is evident in various online discussions and support forums where users frequently inquire about issues with Spectrum discontinuing email service for new accounts or encountering problems with existing Charter/Spectrum email accounts. The general trend for many large ISPs is to reduce the operational overhead of providing email hosting directly to end-users, instead focusing on their core internet, TV, and mobile services. This also means fewer resources are dedicated to maintaining legacy systems like robust feedback loops for external senders.
For email senders, this means that while you might still deliver emails to Spectrum addresses (e.g., @charter.net, @spectrum.net, @twc.com, @roadrunner.com), you cannot rely on a formal feedback loop from them to report spam complaints. This makes proactive email deliverability management even more crucial when sending to these domains.
What is an email feedback loop and why does it matter?
An email feedback loop (FBL), also known as an ISP feedback loop or complaint feedback loop, is a system implemented by Internet Service Providers (ISPs) to inform legitimate bulk email senders when their recipients mark an email as spam. When a subscriber clicks the “report spam” or “junk” button in their inbox, the FBL sends an anonymous notification back to the sender through a complaint report.
This mechanism is incredibly important for maintaining a good sender reputation. High spam complaint rates can lead to an IP address or domain being added to a blocklist (or blacklist), resulting in email delivery issues. By receiving FBL reports, senders can quickly identify which campaigns or segments are generating complaints and remove those subscribers from their lists, thus improving their overall email deliverability. Without an FBL, you might only discover high complaint rates when your emails start bouncing or landing in the spam folder at a significant rate, which can be much harder to recover from.
Many major inbox providers still offer FBLs, such as Yahoo and Gmail. These FBLs are crucial for modern email marketing strategies. Learn more about what a feedback loop is to further your understanding. For a comprehensive list, you can check which other ISPs offer feedback loops.
Proactive complaint management
Early detection: Identifies high-complaint segments quickly.
Improved deliverability: Allows for timely removal of problematic subscribers, reducing blocklist risk.
Better sender reputation: Keeps your sending practices aligned with ISP expectations.
Delayed detection of issues
Increased spam rate: Complaints go undetected, leading to higher rates at the ISP.
Blacklisting risk: Higher chance of your IP or domain being added to a blocklist without warning.
Reduced inbox placement: Emails more likely to land in spam folders, impacting campaign performance.
Navigating deliverability without a Charter.net feedback loop
Given the absence of a formal Charter.net (Spectrum) feedback loop, senders must adopt alternative strategies to maintain strong email deliverability to these domains. The key is to focus on proactive list management, strict adherence to best practices, and consistent monitoring of email performance metrics. This approach helps mitigate the risks associated with undetected spam complaints.
One important area is managing email delivery blocks from Spectrum/Charter. While Charter may not have a formal FBL, some historical sources suggest unblock@charter.net was once a contact point for delisting requests. However, this is not a substitute for an FBL and its effectiveness in the current Spectrum landscape is questionable. Instead, focus on preventing issues from arising in the first place.
This involves adhering to the highest standards of email hygiene. Regularly clean your mailing lists to remove inactive subscribers and hard bounces. Ensure all subscribers have explicitly opted in to receive your emails, preferably using a double opt-in process. This minimizes the chance of recipients marking your emails as spam, which is often the primary cause of poor deliverability and blacklisting (or blocklisting).
Maintaining a healthy sender reputation
List hygiene: Regularly remove inactive users and bounced email addresses.
Explicit consent: Use double opt-in to ensure subscribers genuinely want your emails.
Engagement monitoring: Pay close attention to open and click rates as indicators of content relevance.
Email authentication: Properly configure SPF, DKIM, and DMARC records to verify your sending domain.
Alternative strategies for managing recipient feedback
Since you can't rely on a dedicated FBL from Spectrum (Charter.net), you need to leverage other signals and tools to understand how your emails are performing. Monitoring your email metrics is paramount. Pay close attention to your bounce rates, particularly soft and hard bounces, as these can indicate problems with recipient addresses. High bounce rates can negatively impact your sender reputation, making it harder to reach the inbox even for legitimate emails.
Beyond bounce rates, closely track your open rates and click-through rates. A significant drop in these metrics for a specific segment, or to domains like Spectrum, might signal that your emails are landing in the spam folder or that recipients are disengaging. Also, ensure your emails include a clear and easy-to-find unsubscribe option to allow uninterested subscribers to opt-out gracefully rather than resorting to the spam button. Implementing a List-Unsubscribeheader is a best practice here.
Furthermore, regularly check blocklist monitoring services. Even without a direct FBL, if your emails cause significant complaints at Spectrum, your IP or domain might end up on a general or private blocklist used by many ISPs. Being proactive with your email hygiene and monitoring available deliverability metrics are your best defense against such issues. Also, ensure your DMARC records are correctly set up and DMARC reports are monitored, as these provide valuable insights into authentication failures and potential abuse patterns across all recipients, not just those at Spectrum.
Metric
Why it matters
Actionable insight
Bounce rate
High rates indicate invalid or problematic addresses. Includes soft and hard bounces.
Remove hard bounces immediately; investigate soft bounces.
Open rate
Indicates engagement; low rates can signal spam folder delivery or disinterest.
Test subject lines, content, and sending frequency. Segment disengaged users.
Click-through rate (CTR)
Reflects how engaging your content is. Low CTR can imply irrelevant content.
Improve content relevance, calls to action, and segment targeting.
Unsubscribe rate
Shows how many recipients actively opt-out. High rates suggest dissatisfaction.
A healthy alternative to spam complaints. Offer clear unsubscribe options.
Spam complaint rate (ESP)
Provided by your Email Service Provider (ESP) from other FBLs. Crucial for reputation.
Prioritize removing complainers immediately to protect sender reputation.
Staying vigilant in a changing email landscape
While the formal Charter.net feedback loop is no longer functional, the principles of good email deliverability remain the same. Proactive list management, a strong focus on recipient engagement, and diligent monitoring of all available email metrics are essential. Adapting to the evolving landscape of ISP policies and maintaining robust email authentication practices will continue to be critical for ensuring your messages reach the inbox.
Views from the trenches
Best practices
Ensure all subscribers have explicitly opted into your mailing list using a double opt-in process.
Segment your email list based on engagement and send more frequently to highly engaged users.
Provide clear and easy-to-find unsubscribe options in every email to reduce spam complaints.
Regularly monitor your bounce rates, open rates, and click-through rates across all campaigns.
Common pitfalls
Relying solely on FBLs from other ISPs to gauge deliverability to Spectrum/Charter domains.
Failing to remove inactive or bouncing email addresses from your list regularly.
Ignoring subtle dips in engagement metrics which could indicate underlying deliverability issues.
Not having robust email authentication (SPF, DKIM, DMARC) properly configured and monitored.
Expert tips
Implement a preference center to allow subscribers to customize content or frequency, reducing opt-outs.
Use a reputable Email Service Provider (ESP) that actively monitors ISP changes and provides deliverability insights.
Periodically re-engage inactive subscribers with targeted content or remove them to protect your sender reputation.
Beyond technical checks, focus on providing valuable content that resonates with your audience.
Expert view
Expert from Email Geeks says the Charter.net feedback loop has been non-functional for a while, meaning senders need to rely on other indicators for deliverability at Spectrum.
2023-07-01 - Email Geeks
Marketer view
Marketer from Email Geeks says they stopped seeing FBL reports from Charter years ago, and now they primarily monitor engagement metrics for Spectrum addresses.
Spam complaint rate (ESP)
