Why does Gmail List-Unsubscribe only work on the second attempt?
Michael Ko
Co-founder & CEO, Suped
Published 3 May 2025
Updated 19 Aug 2025
8 min read
It can be incredibly frustrating for recipients and email senders alike when the List-Unsubscribe button in Gmail seems to require two clicks to actually work. A user clicks it once, confirms, but the button remains, and they're still on the list. Only after a second interaction, perhaps selecting a different option, does the unsubscribe actually register. This isn't just an inconvenience, it's a critical deliverability issue that can impact sender reputation and inbox placement.
This puzzling behavior, where the initial unsubscribe attempt fails and a second one succeeds, often stems from a specific technical misconfiguration on the sender's side. It's usually related to how the server handles different types of web requests for the unsubscribe link. Understanding this technicality is key to resolving the issue and ensuring a smooth, single-click unsubscribe experience for your subscribers, which is increasingly important for maintaining good standing with mailbox providers like Gmail.
Ignoring these subtle failures can lead to higher spam complaints, diminished sender reputation, and ultimately, emails landing in the spam folder instead of the inbox. This article will break down why this happens and what steps you can take to fix it.
Understanding List-Unsubscribe headers
The List-Unsubscribe header is a crucial element in email deliverability, allowing recipients to easily opt out of mailing lists. Historically, this header, defined in RFC 2369, supported two main methods: a mailto: address and an http/https URL. The mailto: option triggers an email sent to a specific address, while the URL directs the user to an unsubscribe page.
With the rise of user-friendly email clients and the need for a seamless user experience, RFC 8058 introduced the List-Unsubscribe-Post header. This header enables a one-click unsubscribe mechanism, sending a POST request directly to the specified URL without requiring the user to visit a landing page or confirm via email. Mailbox providers like Google and Yahoo are increasingly enforcing this standard to improve user experience and reduce spam complaints. For more details, see how Gmail and Yahoo's new requirements work.
Here's an example of correctly formatted List-Unsubscribe headers:
When Gmail's unsubscribe button (the one next to the sender's email address) is clicked, it first attempts to perform a one-click unsubscribe by sending a POST request to the URL specified in the List-Unsubscribe-Post header. If your server is configured to block or improperly handle POST requests to that specific URL, the first attempt will fail silently from Gmail's perspective. This is a common pitfall that leads to the perceived two-click unsubscribe behavior.
Upon failure of the initial POST request, Gmail then offers the user a fallback option. This often presents as a slightly different pop-up or a direct link to Go to Website. When the user clicks this, it typically triggers a GET request to the unsubscribe URL. Since web servers are generally configured to handle GET requests for page loads, this second attempt usually succeeds, leading to the user being unsubscribed.
The key takeaway here is that the problem isn't with Gmail's feature itself, but with the server's readiness to receive and process the expected POST request for an instant unsubscribe. If the server only accepts GET requests for the unsubscribe URL, the initial RFC 8058 compliant attempt will fail, creating a frustrating experience and potentially leading to spam complaints because users feel trapped.
Compliance with one-click unsubscribe requirements
The distinction between RFC 2369 and RFC 8058 is critical for modern email deliverability. With new requirements from Google and Yahoo for bulk senders, one-click unsubscribe is no longer just a best practice; it's a mandatory requirement to ensure your emails reach the inbox. Failure to implement this correctly can lead to severe deliverability issues, including emails being sent directly to the spam folder or even your domain being added to an email blacklist (or blocklist).
The primary goal of these new requirements, including the one-click unsubscribe, is to improve the user experience and reduce unwanted email. When it's easy for users to opt out, they are less likely to mark emails as spam, which positively impacts your sender reputation. Conversely, if unsubscribing is difficult or broken, users will resort to marking your emails as spam, signaling to mailbox providers that your emails are unwanted.
This table outlines the key differences between the traditional and modern unsubscribe methods:
Feature
RFC 2369 (Traditional)
RFC 8058 (One-Click)
Method
mailto: or HTTP GET request
HTTP POST request
User Experience
Often requires multiple steps (e.g., confirmation page, sending email)
Immediate unsubscribe with a single click in the email client
Compliance
Basic standard, less effective for reputation
Mandatory for bulk senders to maintain good standing with major providers
Fixing the two-click unsubscribe issue
The core of the Gmail two-click issue is often a server-side misconfiguration preventing the initial POST request from being processed correctly. To fix this, you'll need to ensure your unsubscribe URL is set up to accept and respond to HTTP POST requests. Here's a quick guide:
Check your List-Unsubscribe headers: Ensure both List-Unsubscribe and List-Unsubscribe-Post headers are present and correctly formatted in your email. The List-Unsubscribe-Post should point to a unique URL capable of handling POST requests.
Verify server configuration: Work with your web development or server administration team to confirm that the unsubscribe URL is configured to accept HTTP POST requests. Sometimes, firewalls or web server settings might inadvertently block POST requests to specific endpoints.
Implement robust unsubscribe logic: Ensure your backend system instantly processes the unsubscribe request upon receiving a POST request. This means removing the user from the mailing list immediately, without requiring further action or confirmation.
Test your unsubscribe process: Send test emails to a Gmail account and attempt the one-click unsubscribe. Monitor your server logs to confirm that the POST request is received and processed successfully on the first attempt.
By proactively addressing these technical aspects, you can significantly improve your email deliverability and avoid common pitfalls that lead to emails going to spam. If you're encountering persistent issues with emails reaching the inbox, you may need a more comprehensive strategy to boost your deliverability rates.
Problem vs. solution
The problem
The unsubscribe link only supports GET requests, causing the initial POST request from Gmail to fail, requiring a second, manual click.
Impact on deliverability
Increased spam complaints: Users frustrated by difficult unsubscribes will mark emails as spam.
Damaged sender reputation: Higher spam rates lead to lower trust from mailbox providers.
Configure your unsubscribe URL to accept HTTP POST requests as defined by RFC 8058.
Benefits for deliverability
Reduced spam complaints: Easy opt-out means fewer spam reports.
Improved sender reputation: Signals good sending practices to mailbox providers.
Enhanced inbox placement: Higher likelihood of reaching the primary inbox.
Final thoughts
The Gmail List-Unsubscribe issue, where it seems to only work on the second attempt, often comes down to a fundamental mismatch in how your server handles unsubscribe requests versus what modern email clients expect. The initial one-click unsubscribe attempt from Gmail relies on an HTTP POST request, as mandated by RFC 8058. If your server is not configured to accept these POST requests, the first attempt will fail.
The subsequent, successful attempt is a fallback mechanism where Gmail directs the user to a web page, typically using a GET request. This usually works because web servers are inherently designed to handle GET requests for accessing URLs. To ensure your unsubscribe functionality works seamlessly on the first click, it's imperative to properly configure your server to receive and process POST requests for your List-Unsubscribe-Post URL. This compliance is vital for maintaining a strong sender reputation and ensuring your emails consistently reach the inbox.
Views from the trenches
Best practices
Ensure your unsubscribe URL is configured to accept and process POST requests for RFC 8058 compliance.
Always include both mailto and URL options in your List-Unsubscribe header to provide flexibility for different email clients and user preferences.
Regularly test your unsubscribe process from various email clients to catch any unexpected behavior early.
Common pitfalls
Forgetting to enable POST request handling on your unsubscribe endpoint, leading to two-click unsubscribes.
Not including the mailto: option in your List-Unsubscribe header, limiting unsubscribe methods.
Relying solely on the web-based unsubscribe link without implementing one-click functionality.
Expert tips
Validate your List-Unsubscribe headers using an email header analyzer to ensure they are correctly formed.
Keep your unsubscribe logic simple and efficient, avoiding unnecessary redirects or complex user flows.
Review your server logs for failed POST requests to your unsubscribe URL to diagnose hidden issues.
Expert view
Expert from Email Geeks says that the customer's URL was blocking POST requests. The initial attempt from Gmail was a POST request, and when that failed, it appeared to fall back to a GET request with the second pop-up.
2024-02-27 - Email Geeks
Expert view
Expert from Email Geeks says that Gmail sometimes won't display the in-platform unsubscribe button if they don't trust the sender's reputation or the link domain reputation.
Gmail.
Google and 
Yahoo are increasingly enforcing this standard to improve user experience and reduce spam complaints. For more details, see how Gmail and Yahoo's new requirements work.
new requirements from 
