What is EMPS and how does it relate to opt-out lists and email marketing?
Matthew Whittaker
Co-founder & CTO, Suped
Published 22 Apr 2025
Updated 15 Aug 2025
8 min read
Email marketing is a powerful tool for businesses, but it comes with responsibilities. A key aspect of responsible email marketing is respecting recipient preferences, particularly when they no longer wish to receive communications. This is where the concept of opt-out lists and services like the Email Preference Service (eMPS) come into play.
Understanding how these mechanisms work and their role in maintaining good sender reputation is crucial. Failing to properly manage recipient preferences can lead to deliverability issues, poor engagement, and even legal repercussions.
I often see confusion around these terms and how they intersect with broader email security and deliverability practices. Let's delve into what eMPS is, its relationship to general opt-out lists, and why respecting these preferences is paramount for effective email marketing.
What is EMPS?
The Email Preference Service (eMPS) is a specific program designed to help consumers reduce unsolicited commercial emails. It's operated by the Association of National Advertisers (ANA), which is a key industry body. The idea behind eMPS is to provide a centralized database where consumers in the United States can register their email addresses to indicate they do not wish to receive commercial messages from participating companies. Marketers can then use this list to scrub their own mailing lists.
Historically, the eMPS was a significant tool for consumers seeking to reduce marketing clutter. Its effectiveness, however, relies on marketers proactively accessing and using the list to cleanse their outreach. While still available, its impact has somewhat diminished compared to direct unsubscribe mechanisms built into email platforms and applications. The ANA provides information on their DMAchoice service regarding how consumers can use eMPS to reduce unwanted mail and emails.
The purpose of eMPS
Consumer control: It provides a formal way for individuals to opt out of receiving commercial email from a wide range of companies.
Industry self-regulation: The service encourages marketers to respect consumer preferences and reduce unsolicited mail, promoting better industry practices.
Supplement to direct unsubscribes: While direct unsubscribe links are crucial, eMPS offers an additional layer for broad opt-out from multiple senders.
Although eMPS provides a broad mechanism for consumers, its influence on individual email marketing campaigns is often less direct than compliance with the CAN-SPAM Act in the U.S. or GDPR in Europe. These regulations legally mandate that marketers provide a clear unsubscribe option in every commercial email and honor those requests quickly. You can learn more about how to stop unwanted junk mail directly from the FTC.
The importance of opt-out lists
Opt-out lists, also known as suppression lists or do-not-contact lists, are fundamental to ethical and legal email marketing. They contain the email addresses of individuals who have explicitly requested not to receive further marketing communications from a particular sender or organization. Maintaining accurate and up-to-date opt-out lists is not just a best practice, but a legal requirement in many jurisdictions around the world. For instance, the CAN-SPAM Act requires marketers to honor opt-out requests within 10 business days.
The importance of these lists extends beyond legal compliance. Sending emails to recipients who have opted out can severely damage a sender's reputation, leading to lower deliverability rates, increased spam complaints, and potential placement on blocklists (or blacklists). Internet service providers (ISPs) and email service providers (ESPs) actively monitor for these behaviors and penalize senders who don't respect unsubscribe requests.
Opt-in approach
Subscribers actively agree to receive emails, typically by checking a box or submitting a form. This is the preferred method for building high-quality lists. It means the recipient has given clear and affirmative consent.
Consent: Explicit permission is obtained before sending any marketing emails.
Engagement: Leads to higher engagement rates and fewer spam complaints due to genuine interest.
Opt-out approach
Recipients are automatically added to an email list, but are given the option to unsubscribe or opt out later. This method is generally not recommended for new subscribers and is often restricted by privacy regulations.
Default inclusion: Assumes consent unless the user actively declines.
Risk: Higher likelihood of spam complaints and negative sender reputation if not carefully managed.
While eMPS is a specific, centralized opt-out list primarily for the US market, the concept of an opt-out list is far broader. Every legitimate sender should maintain their own internal opt-out (or suppression) list derived from unsubscribe requests received directly from their recipients. These internal lists are critical for compliance and maintaining good sender reputation.
EMPS vs. direct unsubscriptions and blocklists
eMPS operates as a consumer preference service where individuals proactively register their addresses. It's a voluntary mechanism for marketers to cleanse their lists before sending. This contrasts with the direct unsubscribe link that is legally mandated in every commercial email and must be honored by the sender when a recipient explicitly clicks it. Direct unsubscribe requests are immediate and binding for that specific sender.
Blacklists (or blocklists) are another distinct concept. While opt-out lists are about consumer preference, blacklists are databases of IP addresses or domains known for sending spam or unsolicited mail. Inclusion on a blacklist is a consequence of poor sending practices, which can include failing to honor opt-out requests, sending to old or unengaged addresses, or having high spam complaint rates. An email going to a blacklisted domain will often be rejected outright, unlike an email sent to an opted-out address that might still be delivered if the sender hasn't scrubbed their list, albeit with negative consequences.
The relationship is indirect: failing to respect opt-out requests can lead to higher spam complaints, which in turn increases the risk of being listed on a blacklist. This significantly impacts email deliverability. For example, some large email providers, such as Google and Yahoo, have tightened their sender requirements, making it even more crucial to manage your sender reputation effectively.
Feature
eMPS
Direct opt-out
Email blacklist/blocklist
Purpose
Centralized consumer preference to reduce unsolicited email.
Individual request to stop receiving emails from a specific sender.
List of senders (IPs, domains) with poor sending reputation.
Mechanism
Consumer registers with a third-party service.
Recipient clicks an unsubscribe link in an email.
Managed by anti-spam organizations or ISPs.
Impact on sender
Marketers are encouraged to scrub lists, but compliance is voluntary.
Legal obligation to remove from list within a specific timeframe.
Emails may be blocked, quarantined, or sent to spam folders.
Deliverability
Indirectly affects deliverability if used by marketers.
Directly impacts deliverability and sender reputation if not honored.
Directly impacts deliverability; severe consequence for senders.
Understanding these distinctions is essential for any email marketer. While eMPS offers a macro-level approach, the micro-level management of direct unsubscribe requests and avoiding blacklists is where the majority of your deliverability efforts should be focused. You can check out more details about how email blacklists work for a deeper dive.
Effective management of opt-out requests
For email marketers, the most effective strategy for managing recipient preferences centers around compliance and proactive list hygiene. This means ensuring every commercial email has a clear and functional unsubscribe link. The one-click unsubscribe header is now a requirement for large senders to comply with new sender requirements from major providers like Google and Yahoo.
It's also vital to process unsubscribe requests promptly, ideally automatically. Delaying or failing to honor opt-out requests can lead to severe penalties, including fines and irreversible damage to your sender reputation. Recipients who repeatedly try to unsubscribe but cannot will often mark your emails as spam, which is a significant negative signal to ISPs. This can lead to your emails going to spam or even being blocked entirely. This is one of the main reasons why companies ignore opt-out requests.
Example of a List-Unsubscribe header for one-click unsubscribeHTTP
Finally, regularly cleaning your email lists and focusing on engaged subscribers is a crucial proactive measure. Remove inactive subscribers and re-engage those who have shown signs of disinterest before they resort to unsubscribing or marking your emails as spam. This approach, combined with respecting all opt-out requests, will significantly improve your email deliverability and overall marketing success.
Views from the trenches
Best practices
Always include a prominent and easy-to-find unsubscribe link in every commercial email you send.
Process all unsubscribe requests immediately and automatically to ensure timely removal from your lists.
Regularly clean your email lists by removing inactive or unengaged subscribers to improve sender reputation.
Implement one-click unsubscribe (List-Unsubscribe header) to meet modern sender requirements.
Common pitfalls
Failing to process unsubscribe requests promptly, leading to increased spam complaints.
Making the unsubscribe process difficult or confusing, frustrating recipients.
Sending commercial emails to contacts who have explicitly opted out or marked your emails as spam.
Not understanding the difference between eMPS, direct opt-outs, and email blacklists.
Expert tips
Monitor your spam complaint rates closely through Postmaster Tools to identify potential issues early.
Segment your audience and tailor content to reduce unsubscribe rates and increase engagement.
Consider re-engagement campaigns for inactive subscribers before permanently removing them from your list.
Prioritize explicit consent (opt-in) over assumed consent (opt-out) for building high-quality lists.
Expert view
Expert from Email Geeks says eMPS is the DMA's version of a global opt-out list, but its relevance has diminished over time. Its primary use case now is for marketers to wash their lists against the data to ensure compliance.
2020-08-12 - Email Geeks
Marketer view
Marketer from Email Geeks says intentionally spamming people who have explicitly opted out would likely not go well for the sender due to severe negative consequences for deliverability.
2020-08-14 - Email Geeks
Maintaining a healthy email ecosystem
The Email Preference Service (eMPS) and general opt-out lists are both integral to maintaining a healthy email ecosystem, albeit in different ways. While eMPS offers a macro-level tool for consumer choice, the day-to-day responsibility for honoring unsubscribe requests falls squarely on individual marketers.
Adhering to legal requirements and ethical sending practices, such as providing clear unsubscribe options and promptly removing recipients from your lists, is non-negotiable. This not only ensures compliance but also safeguards your sender reputation and improves overall email deliverability. Failing to do so can lead to serious consequences, including being placed on a blacklist (or blocklist), which can severely impact your ability to reach the inbox.
Ultimately, respecting recipient preferences builds trust and fosters a positive relationship with your audience, leading to more engaged subscribers and more successful email marketing campaigns. Focus on building an opt-in list and honoring every unsubscribe. This is the path to long-term deliverability success.
Google and 
Yahoo, have tightened their sender requirements, making it even more crucial to manage your sender reputation effectively.
