List-Unsubscribe Header: Why It’s a Big Deal

A list-unsubscribe header has become a more common and expected feature in email marketing, driven by industry best practices and legal requirements in different parts of the world. Most major mailbox providers now support list-unsubscribe headers to varying degrees, with some displaying visible one-click unsubscribe links and others processing them behind the scenes.

The use of list-unsubscribe headers is only likely to continue growing as they provide a user-friendly way for email marketing subscribers to quit email lists without issues.

In this detailed guide, we explain what a “list-unsubscribe” header is, how it works, and the numerous advantages of implementing it in your email marketing campaigns.

What is a List-Unsubscribe Header?

The list-unsubscribe header or email unsubscribe header is part of an email header; it provides a standardized way for email recipients to unsubscribe from mailing lists.

Including this unsubscribe header in an email allows email clients to display an “Unsubscribe” option at the top of an email, typically near the sender’s email address or the email subject line.

This feature makes it easier for recipients to opt out of receiving further emails from a particular mailing list without having to navigate to a separate unsubscription page or reply to the email with an unsubscribe request.

By providing a standard way to handle unsubscribes, the list-unsubscribe email header improves the user experience. It also has a benefit for email marketers — it reduces the chances of recipients marking emails as spam. Being marked as a spam email sender is much worse than a high email unsubscribe rate.

It’s a win-win for both senders and recipients, as the unsubscribe email header encourages responsible and user-friendly email marketing practices.

Why was the List-Unsubscribe Header Created?

The list-unsubscribe header is the result of a collaborative effort within the email industry. The goal was to establish standards that benefit both senders and recipients. By adopting a consistent approach to unsubscribes, email providers and email marketers worked together to create a more trustworthy email ecosystem.

Before implementing list-unsubscribe headers, users often had to scroll through emails desperately seeking unsubscribe links. If that sounds bad, the second option was much worse — email users had to visit external websites and find a page where they could opt out of mailing lists.

Comparatively, the unsubscribe email header is straightforward.

Before these headers existed, users would resort to marking messages as spam; it was simpler than finding an unsubscribe link. By making the unsubscribe process clear, the list-unsubscribe header reduces spam complaints, which is favorable to marketers.

Additionally, regulations governing email marketing practices require senders to provide an easy way for recipients to opt out of future communications. The list-unsubscribe header helps email senders comply with such regulations.

Over the past few years, this feature has also seen widespread adoption.

Which mailbox providers support list-unsubscribe headers?

Introduced to enhance the overall email experience for users, this header addition cut down on the rate of legitimate emails being marked as spam and encouraged email senders to comply with regulations.

Why List-Unsubscribe Headers are Important for Email Marketers

You might be thinking: “I’ve already included an unsubscribe link further down the email, why should I include one at the top, the first thing a reader will see? Why tempt them to opt out?”

The reason you should provide a list-unsubscribe header is: the moment your email recipient decides to bail, there’s no stopping them. And if this person struggles to find the unsubscribe option, they’re going to go for the next best option: Report as spam.

Between the two, you’d rather have your subscribers choose to unsubscribe. Mailbox providers take spam reports more seriously than unsubscribes. Excessive spam reports can even get you kicked off your own email services platform.

So let’s sum it up:

List-unsubscribe headers show your reader you’re confident in the value you provide.
Adding a list-unsubscribe header improves your sender score and, in the process, improves email deliverability. It’s safe to assume mailbox providers greatly appreciate you including a list-unsubscribe header.
Your email sender reputation won’t get hit and your subscribers will appreciate you offering them an easy out.
Including a list-unsubscribe header makes you seem professional and your company reliable.
It’s easy to implement.
Providing unsubscribe headers lets you meet CAN-SPAM requirements and adhere to the GDPR compliance checklist.
Do you really want to email uninterested subscribers? Not only does that increase your email marketing costs, but it’s also bad for email engagement when your recipients delete your emails without reading them.

Additionally, include this text in your email body: “If you’d like to unsubscribe and stop receiving these emails click here.”

Let’s now learn more about how this feature functions.

How List-Unsubscribe Header Works

The email list-unsubscribe header provides a standardized way for email recipients to unsubscribe from mailing lists directly from their email clients.

There are two ways of including a list-unsubscribe header — the mailto method and the URL method.

In the mailto method, users can unsubscribe by sending an email. The URL method involves visiting a link to unsubscribe. We will explain these in detail shortly, but here’s how a typical email recipient experiences the list unsubscribe header.

These are the 8 general steps explaining how the feature works:

For the feature to work, the list-unsubscribe header must be a part of the email headers. One or more URLs can be added to this header, pointing to the unsubscribe web pages for the mailing list. If the mailto method is used, an email address must be configured to receive unsubscription requests.
When this email reaches recipients, their email clients process the list-unsubscribe header information.
Email clients that support the list-unsubscribe header integrate this information into their user interface. This often results in the display of an “Unsubscribe” or similar option within the email client itself.
When a recipient decides to unsubscribe from the mailing list, they click on this Unsubscribe option.
Clicking it triggers the URL or activates the email link specified in the list-unsubscribe header.
Depending on the mailing list’s configuration, the recipient may be directed to a web page where they can confirm their desire to unsubscribe or they will be asked to send an unsubscription email to the address you specified.
The unsubscribe process, whether through a confirmation page or an automated removal, is carried out.
Finally, the recipient’s email address is taken off the mailing list.

Next, let’s check out which providers support list-unsubscribe headers.

Which Mailbox Providers Support List-Unsubscribe Headers?

Before you implement list-unsubscribe headers, you might be wondering — do the major mailbox providers even support it?

Here’s a list of the more renowned names that do, alongside the unsubscribe method:

Mailbox provider	Mailto method	URL method
Gmail	✅	✅
Gmail app on iOS and Android	✅	✅
Outlook	✅	❌
Yahoo! Mail	✅	❌
Apple Mail on macOS	✅	❌
Apple Mail on iOS	✅	❌

Mailbox providers that support list-unsubscribe headers

Considering Gmail, Apple Mail, and Outlook serve about 92% of the global email market, we’d say yes; it does make sense to implement list-unsubscribe headers in your emails!

How to Add List-Unsubscribe Header to Your Emails

Adding a list-unsubscribe header to your emails involves modifying the email headers before sending them. And you have two ways of doing this — you can use the mailto method or the URL method. If you wish to offer an easy unsubscribe option in your email headers, you can implement one, or both, of the two methods.

The Mailto Method

To use the Mailto unsubscribe method, you must first create a unique e-mail address for unsubscribe requests; ensure you reserve this account purely for unsubscriptions. The unsubscribe header in your emails will include this email address.

When recipients click on the “Unsubscribe” option in their email client, it opens their default email application with a pre-filled email to the address/addresses you specified. Once they press send, you will receive their unsubscribe request.

Typically, the code inserted into the header looks like this: “List-Unsubscribe:

<mailto:unsubscribe@yourcompany.com>”

If you use this method to deal with unsubscribes, you must constantly monitor the inbox so you can promptly honor the requests that come in.

Here’s a table comparing the pros and cons of Mailto method:

Pros	Cons
It’s more popular and hence more familiar to users.	In a few cases, the mailto method may skip the confirmation step, potentially leading to accidental unsubscribes.
It is simple to implement.	The unsubscribe email account needs constant monitoring.
It immediately initiates an unsubscribe request from a recipient.
It has widespread acceptance among mailbox providers	It’s more popular and, hence, more familiar to users.

Pros and Cons of using the mailto method in list-unsubscribe headers

Now let’s examine the second type of list-unsubscribe header.

The URL Method

The method is slowly building up in popularity these days, and here’s how it works.

For the URL method, you will have to create a landing page with a form/radio buttons for the unsubscription process. The list-unsubscribe header in your emails will lead users to this page to unsubscribe them.

To add this feature, here is the snippet of code you will have to include in the header: “List-Unsubscribe:

<https://yourcompany.com/unsubscribe>”

When recipients click on Unsubscribe, the list-unsubscribe URL will lead them to the web page you created. Here, they can confirm the unsubscribe reason and complete the unsubscription. You can also allow immediate removal without confirmation.

Ensure users don’t need to log in on this page because that can be aggravating for people looking to quickly unsubscribe.

Regardless of the method you choose, it’s a good idea to send feedback to the recipients, providing information about the unsubscribe action. This email can include details about the success of the unsubscribe request plus you can express regret to see them go.

Let’s look at the pros and cons of the URL method of list-unsubscribe headers:

Pros	Cons
The URL method may be more popular with users due to immediate confirmation of unsubscription.	Select users may dislike being sent to a web page for unsubscription.
You can create customized unsubscribe processes.	It’s more complicated to create, as compared to the mailto method.
It provides a good opportunity to collect feedback — the reason for unsubscribing.

Pros and Cons of using the URL method in list-unsubscribe headers

Now that you know about both methods, let’s explore how to add this amazing feature to your emails.

Setting Up List-Unsubscribe Headers on Your Email Services Platform

So you’ve locked the method of list-unsubscribe you wish to use — good job!

Here are the 4 key steps to follow next.

On your email platform, locate the page where you can add custom headers to your emails. This is usually an option in your settings page, SMTP server settings, or in the code if you’re sending emails via custom software.
Insert the list-unsubscribe header into the email headers. The header will be either a URL or an email address, depending on the unsubscribe method you choose. You can (and should) include both.
It’s now time to test if the feature works correctly. Send test emails to yourself and verify that the unsubscribe option works as expected.
The success of the list-unsubscribe header depends on email client support for the feature. And since there’s always a chance it could fail or work incorrectly, add alternative methods for recipients to unsubscribe, such as a clear and visible unsubscribe link within the email body.

Another added benefit of list-unsubscribe headers is that most mailbox providers see them in a positive light. Next, let’s look at how popular mailbox services treat list-unsubscribe headers.

The Gmail List Unsubscribe Header in Action

Gmail loves list-unsubscribe headers; as one of the most popular mailbox providers with a user-first approach, it makes sense.

The Gmail list-unsubscribe header function was introduced in 2014, under the name of Auto-Unsubscribe. If you want your emails to make it to Gmail’s Primary Inbox, you must implement it.

List-Unsubscribe Header Example

Below, you can view the different ways the list-unsubscribe function works on the web, Android, and iOS versions of Gmail.

A screenshot of the Gmail list-unsubscribe header in the web version

Why Adding a Gmail List-Unsubscribe Header is Critical

The Gmail spam update indicates Google plans to fight spam with a vengeance — the email giant has made list-unsubscribe headers mandatory for bulk email senders.

It’s part of Google’s campaign to focus on sender reputation a lot more to fight the spam menace. If you email more than 5,000 Gmail users in a day, the company wants you to implement email authentication. It also wants you to make it easier for consumers to opt out of your mailing lists by adding a one-click unsubscribe header.

Google insists that senders implement this feature ASAP; they want subscribers to be able to unsubscribe with a single click in the near future.

Gmail supports both mailto and URL methods of list-unsubscribe headers.

The Outlook List-Unsubscribe Header

Outlook also supports list-unsubscribe headers, but only of the mailto variety.

When Outlook detects a mailto link, it displays an “Unsubscribe” link next to the sender’s email when a list-unsubscribe header is present. The below image indicates the presence of a list-unsubscribe header in the code of an email.

Microsoft is known to evaluate your sender score before showing your email to their service users, so even if the feature may not always work, there is a deliverability benefit to including a list-unsubscribe header in your emails.

How to Create an Unsubscribe Link in Outlook

If you use Outlook to email a list of subscribers, you can include an Outlook unsubscribe button using the steps listed here:

Compose a new email: Open Outlook and start composing a new email.
Add text for the link: Type “Unsubscribe” or a similar phrase in your email body.
Insert the link: Highlight the text, right-click, and select Insert Link (or use Ctrl+K).
Add the unsubscribe URL: Enter the URL for your unsubscribe page or email address for unsubscribe requests.
Test the link: Send a test email to ensure the link works correctly before sending it to your audience.

With this technique, you can add a one-click unsubscribe header to your outgoing Outlook emails.

List-Unsubscribe Header in Apple Mail

Both Gmail and Outlook support list-unsubscribe headers — how about Apple? Does Apple Mail unsubscribe work as well? The answer is yes!

The Apple Mail unsubscribe feature is in line with industry standards. It provides users with a streamlined way to unsubscribe from mailing lists directly from their email clients. This applies to both iOS and macOS.

Apple Mail supports both the URL and mailto methods of the list-unsubscribe header. This allows you to include web-based URLs and/or email addresses in the header, giving your recipients flexibility in how they choose to unsubscribe.

If your email includes the list-unsubscribe header, Apple Mail displays an “Unsubscribe” option within the Mail app on an iPhone or a Mac computer, in a distinct banner, above the email body. On iOS, the banner is visible above your email address whereas on the Mac Mail app, the banner is below your email sender name.

Users can then click on the “Unsubscribe” option, which triggers the specified unsubscribe mechanism — a web-based confirmation page or an email removal process. Apple Mail may provide feedback to the user or sender about the success of the unsubscribe action.

Dos and Don’ts for List-Unsubscribe Headers

If you’re wondering about best practices while implementing list-unsubscribe headers, we’ve got a list of dos and don’ts that should cover all the bases.

Best practices for list-unsubscribe headers

Remember — list-unsubscribe headers help you comply with email unsubscribe laws and support email accessibility guidelines.

Achieve Better Email Deliverability: Knowledge Resources

The Campaign Refinery blog is filled with excellent articles to help you become a better email marketer.

Here are 11 related topics you may find interesting:

Campaign Refinery: In Favor of List-Unsubscribe Headers

We believe the sender-recipient relationship is a symbiotic connection and should be treated with respect. When you add a list-unsubscribe header to your emails, you are showing respect to your recipients for their time and attention.

We highly recommend you build a list of subscribers wholly interested in receiving your content. That is also why we recommend the double opt-in method when onboarding new prospects.

The best part of adding the list-unsubscribe header feature is that it keeps recipients away from the “Report spam” button. Spam reports can rapidly drag down your sender reputation.

At Campaign Refinery, we are strongly in favor of marketers following best practices to ensure your sender score never takes a hit, and including a list-unsubscribe header definitely counts as a huge plus.

Besides this feature, here are additional tips to improve email deliverability:

Constantly monitor your email IP address score
Check domain reputation periodically,
Send relevant email content,
Implement an email segmentation strategy,
Use email validation,
Implement email security protocols,
Work with a reputable email platform.

When it comes to deliverability, there are no two ways about it — Campaign Refinery’s deliverability rates crush the competition.

To experience what it’s like to see your inboxing rates skyrocket, sign up to become a Campaign Refinery customer today!

FAQ

How Does Apple Mail Unsubscribe Work?

Apple Mail detects unsubscribe headers in emails and offers users a convenient one-click option to unsubscribe directly from the app.

How to Add an Unsubscribe Link to an Email in Outlook?

Insert an unsubscribe URL or email address into your message by highlighting text, selecting “Insert Link,” and adding the appropriate details.

What is an Unsubscribe List?

An unsubscribe list refers to the list-unsubscribe function, which makes it easy for email recipients to unsubscribe from an email list.

What is the Email Marketing Unsubscribe Process?

The unsubscribe process involves a recipient clicking a link or button to be removed from an email list, which is typically handled by email marketing software.

Why Unsubscribe Never Works?

Unsubscribe links may fail if the sender is non-compliant with email laws, uses deceptive practices, or the recipient’s request isn’t processed correctly.

Does Email Unsubscribe Work?

Yes, when implemented properly by legitimate senders, unsubscribe links effectively remove recipients from email lists.