Loops.so is a modern email platform for SaaS product marketing, popular with startups shipping their first email programs thanks to a clean dashboard, native audiences, and automated workflows. The unsubscribe mechanism uses a Handlebars-style merge variable in template bodies, and Loops handles RFC 8058 one-click headers automatically for every send (marketing and transactional alike, unlike most transactional-first competitors). Mailing groups let subscribers opt out of one topic (Product Updates, Weekly Digest) without leaving the account entirely.
Loops unsubscribe link
| Tag syntax | {{ unsubscribeUrl }} |
| Placement | Auto-embedded in every send footer |
| Scope | Per Mailing Group, plus account-wide fallback |
| Config path | Settings > Mailing Groups > Manage groups |
| RFC 8058 one-click | Yes, automatic for all sends including transactional |
How to add the unsubscribe tag in Loops
Place the merge tag exactly as shown below in the email template. Loops replaces it at send time with a signed URL scoped to the recipient and campaign.
{{ unsubscribeUrl }}For custom HTML templates, wrap the tag in an anchor to render a proper hyperlink in the delivered email:
<a href="{{ unsubscribeUrl }}">Unsubscribe from this list</a>Auto-embedded in every send footer
Yes, automatic for all sends including transactional The recipient's mailbox provider (Gmail, Yahoo) uses the List-Unsubscribe-Post header to expose the native one-click button on the message. Requires domain authentication with DKIM and DMARC.
Loops applies the unsubscribe check on transactional sends by default, which is unusual. If your transactional message triggers on a critical event (password reset, order confirmation), an unsubscribed contact still gets the message only if the Mailing Group is set as "Ignore unsubscribe status" in the Group settings. Otherwise, transactional messages skip unsubscribed contacts silently.
Testing your Loops unsubscribe link
- Send a test message to a controlled Gmail address you own via the Loops campaign preview action
- Click the footer unsubscribe link and confirm the opt-out on the landing page
- Check the subscriber or contact record: the status should be Unsubscribed within seconds
- Verify the RFC 8058 headers in Gmail: open the message, click three dots, then Show original. Look for
List-UnsubscribeandList-Unsubscribe-Post: List-Unsubscribe=One-Click
Want the full 222-platform reference?
See the pillar guide with the compliance landscape, the RFC 8058 deep dive, and the unsubscribe tag for every ESP: How to add an unsubscribe link: the complete 2026 guide →
Loops positioning and unsubscribe model
Loops is a modern email platform focused on SaaS product teams, positioned between transactional providers like Postmark and marketing platforms like Klaviyo. It handles both product-triggered emails (welcome, receipts, notifications) and marketing broadcasts from a single interface. The unsubscribe mechanism uses the {{unsubscribeUrl}} handlebars variable in Loops templates, replaced with a signed URL at send time. Marketing broadcasts include a default footer with the variable pre-populated; product-triggered transactional emails skip the unsubscribe link entirely.
Message type classification
Every email in Loops is classified as either transactional (product notifications) or marketing (broadcasts, sequences). The classification is set when creating the campaign template and determines whether unsubscribe headers are applied. Transactional messages skip both the visible unsubscribe footer and the RFC 8058 headers, matching the standard convention that transactional messages are outside opt-out scope. Marketing messages always include both. This separation is enforced at send time and cannot be overridden per-message.
RFC 8058 headers on marketing sends
Loops adds RFC 8058 one-click unsubscribe headers (List-Unsubscribe and List-Unsubscribe-Post) on all marketing sends from authenticated domains. Domain authentication is completed under the Domains section by configuring the required SPF and DKIM records. Loops verifies the records before enabling one-click headers. For accounts sending significant marketing volume to Gmail or Yahoo, this is required to meet the February 2024 bulk-sender enforcement, and Loops customer success guides teams through the setup as part of onboarding.
Suppression list management
Unsubscribed contacts are added to the account-wide suppression list, which blocks all marketing sends but allows transactional messages through. This is critical for SaaS applications: a user who unsubscribes from marketing should still receive password reset emails and shipping notifications. Loops enforces this at send time by checking the suppression list against the message classification. The suppression list is exposed through the Loops API for reconciliation with external product databases.
About the Author
Alaa · LinkedIn
Email infrastructure specialist with 8+ years of hands-on experience in SMTP, deliverability, and email verification. I’ve configured and troubleshot mail systems across Postfix, Exchange, and cloud relays, managed IP reputation and warmup campaigns, and built verification pipelines processing millions of addresses. My work spans DNS authentication (SPF, DKIM, DMARC, BIMI), bounce handling, blocklist monitoring, and compliance frameworks including CAN-SPAM and GDPR. I write every article on SMTPedia to give email professionals, developers, and marketers the accurate, RFC-grounded reference they need.
About SMTPedia
SMTPedia is an independent email industry reference covering SMTP, IMAP, POP3, email deliverability, marketing platforms, DNS authentication, and email verification. Every article is researched from official provider documentation, IETF RFCs, and industry best practices. Settings and configurations are verified quarterly.
We are cited as a source by ChatGPT, Microsoft Copilot, and thousands of email professionals worldwide. Learn more about our editorial process.
