Where can I find comprehensive lists of known disposable email domains to block?
Matthew Whittaker
Co-founder & CTO, Suped
Published 1 Jun 2025
Updated 19 Aug 2025
6 min read
Disposable email addresses (DEAs), also known as temporary or throwaway emails, are a persistent challenge for businesses trying to maintain a clean email list and ensure accurate user data. These addresses are designed to be short-lived, allowing users to sign up for services or access content without revealing their primary email address.
While they might seem harmless, DEAs can significantly impact your email deliverability, sender reputation, and marketing efforts. They often lead to inflated signup numbers, poor engagement rates, and a higher likelihood of hitting spam traps. Effectively identifying and blocking these domains is crucial for protecting your digital assets and ensuring your messages reach legitimate inboxes.
The core challenge lies in the dynamic nature of these domains. New ones emerge constantly, and old ones might reappear or change. Relying on a static blacklist (or blocklist) of known disposable email domains can quickly become outdated. This article will explore where you can find such lists, their limitations, and a more comprehensive strategy for managing them.
The challenge of finding and maintaining lists
Maintaining a comprehensive and up-to-date list of disposable email domains is a continuous battle. Many sources provide lists, but their effectiveness varies based on how frequently they are updated and the methodology used to identify these domains.
One of the most widely referenced community-maintained resources for disposable email domains can be found on GitHub. These repositories often aggregate domains from various sources and are updated by contributors over time. They typically provide the lists in plain text or JSON format, making them relatively easy to integrate into your systems. You might also find discussions on platforms like Reddit forums or developer communities that share insights and curated lists.
However, it is vital to remember that public lists, even those regularly updated, may not always be exhaustive or perfectly accurate. Some might include domains that are no longer disposable, or they might miss newly emerging ones. Always exercise caution and consider validating the lists against your specific needs before implementing them.
Understanding disposable email domains
Disposable email addresses serve various purposes for users, from signing up for free trials without commitment to bypassing email verification requirements. For businesses, accepting DEAs can lead to several negative consequences.
Data quality: They pollute your customer database with temporary or fake contacts.
Spam complaints: Users of DEAs are more likely to mark emails as spam, negatively impacting your sender reputation.
Resource waste: Sending emails to DEAs consumes sending limits and bandwidth without generating genuine engagement.
Limitations of static blocklists
While static lists can provide a baseline, they come with inherent limitations. The landscape of disposable email services is constantly evolving, with new domains appearing daily and existing ones changing their operational patterns. This means a list compiled yesterday might already be incomplete today. Moreover, some larger, legitimate mailbox providers (like Yahoo.com or Gmail.com) can function as disposable in practice if users frequently mark your emails as spam, effectively making them a one-time use address for your brand.
Another concern is the risk of false positives. An overly aggressive blocklist (or blacklist) might inadvertently block legitimate users who happen to use a domain that was previously classified as disposable but has since changed its nature. This can lead to customer frustration and missed opportunities. We have a related article on whether you should block disposable email addresses.
Furthermore, a simple domain match approach might not catch hyper-disposable domains, which are extremely short-lived domains that might only exist for a few hours. These are often used in sophisticated fraud attempts and require more advanced detection methods than a static blocklist can provide.
Implementing a comprehensive strategy
Given the limitations of static lists, a more robust strategy for managing disposable email addresses involves a multi-layered approach. This moves beyond simply finding a comprehensive blocklist (or blacklist) and integrates proactive measures into your email processes.
One effective method is to utilize real-time email verification services. These services often employ a combination of techniques, including regularly updated blacklists (or blocklists), domain analysis, and behavioral patterns, to identify DEAs and other risky email addresses at the point of entry. This proactive validation helps keep your list clean from the outset.
Another strategy involves implementing form-level validation and behavioral analytics. Look for suspicious patterns such as extremely fast sign-ups, unusual user agent strings, or repeat sign-ups from similar IP addresses. While not directly related to domain lists, these tactics complement your blocking efforts by identifying potential abuse that might not be tied to a known disposable domain. Understanding how to identify suspicious email domains and spamtrap networks can further enhance your defenses.
Static blocklists
Pros: Easy to implement, often free and publicly available.
Cons: Quickly outdated, risk of false positives, misses new domains, doesn't catch hyper-disposable domains.
Implementation
Download a list (e.g., from GitHub), upload to your system, and configure your registration forms or email capture points to reject entries matching these domains.
Dynamic email validation
Pros: Real-time updates, lower false positive rates, catches new and hyper-disposable domains, identifies other email quality issues.
Cons: Typically a paid service, requires API integration.
Implementation
Integrate a third-party email validation API into your signup forms, lead capture tools, or CRM. This provides instant verification at the point of data collection.
A good example of how to implement a basic check might look like this, using a list of known domains:
Effectively managing disposable email domains is a critical component of maintaining strong email deliverability and protecting your sender reputation. While publicly available lists can offer a starting point, they are rarely sufficient on their own due to the constant evolution of DEA services.
The most effective approach combines static blocklists (or blacklists) with dynamic email validation services and continuous monitoring. This ensures you are not only catching known threats but also adapting to new ones as they emerge. Prioritizing email list hygiene by preventing DEAs from entering your system will ultimately lead to higher engagement, better deliverability, and more valuable customer relationships.
For ongoing protection, consider regularly reviewing your email engagement metrics and monitoring for unusual patterns that might indicate DEA abuse. Tools that provide insights into your email domain reputation can also help you stay ahead of potential issues.
Views from the trenches
Best practices
Integrate real-time email validation APIs at all signup points to identify and block disposable email addresses instantly.
Regularly review and update your internal blocklists by cross-referencing with community-sourced lists.
Monitor email engagement metrics closely for signs of low engagement, which can indicate a high percentage of DEAs.
Consider implementing CAPTCHA or other anti-bot measures on forms to deter automated DEA signups.
Common pitfalls
Relying solely on static, outdated lists of disposable email domains can lead to many missed DEAs.
Blocking legitimate users due to an overly aggressive or poorly maintained disposable email blocklist.
Failing to adapt blocking strategies as new disposable email services emerge.
Not considering user behavior (e.g., immediate unsubscription) as an indicator of a 'disposable' interaction.
Expert tips
Use domain reputation checks as an additional layer to flag suspicious domains, not just known DEAs.
Analyze signup velocity and IP address patterns to detect automated DEA registrations.
Segment your audience based on engagement, filtering out consistently inactive or non-responsive DEA users.
Remember that some major email providers can effectively become disposable if users mark mail as spam.
Marketer view
Marketer from Email Geeks says that they use a specific GitHub repository for disposable email domains to help manage their lists.
2021-08-10 - Email Geeks
Marketer view
Marketer from Email Geeks mentioned finding a list of about 1,000 domains on Reddit, which they used for their own blocking efforts.
Yahoo.com or 
Gmail.com) can function as disposable in practice if users frequently mark your emails as spam, effectively making them a one-time use address for your brand.
