Mailshake is a cold outreach and sales engagement platform popular with SDRs, agencies, and consultants running personalized cold email campaigns from a Gmail or Outlook mailbox. The unsubscribe mechanism uses a merge variable placed manually in the email body, and Mailshake tracks unsubscribes at the account level via a suppression list synced across all campaigns. Since sends originate from personal mailboxes, RFC 8058 headers depend on the mailbox provider (Gmail Workspace, Outlook 365) and their own DMARC alignment. This guide covers the tag, the account-level suppression, and the mailbox-specific deliverability considerations.
Mailshake unsubscribe link
| Tag syntax | {{unsubscribeLink}} |
| Placement | Manual placement in the email body |
| Scope | Account-wide suppression list |
| Config path | Settings > Unsubscribes > Manage list |
| RFC 8058 one-click | Depends on the sending mailbox (Gmail, Outlook) DKIM setup |
How to add the unsubscribe tag in Mailshake
Place the merge tag exactly as shown below in the email template. Mailshake replaces it at send time with a signed URL scoped to the recipient and campaign.
{{unsubscribeLink}}For custom HTML templates, wrap the tag in an anchor to render a proper hyperlink in the delivered email:
<a href="{{unsubscribeLink}}">Unsubscribe from this list</a>Manual placement in the email body
Depends on the sending mailbox (Gmail, Outlook) DKIM setup 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.
Mailshake account-wide suppression means a prospect who unsubscribes in Campaign A is skipped in every future Campaign B, C, D. This is the correct behavior for cold outreach compliance but surprises agencies running distinct client accounts under the same Mailshake account. Use separate Mailshake accounts per client to segregate suppression pools.
Testing your Mailshake unsubscribe link
- Send a test message to a controlled Gmail address you own via the Mailshake 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 →
Mailshake and cold email sequences
Mailshake is a cold email outreach platform focused on B2B sales prospecting. Its unsubscribe mechanism uses the {{unsubscribe_link}} merge tag, replaced with a signed URL at send time. Mailshake includes the unsubscribe link by default in sequence templates to satisfy CAN-SPAM requirements for US-directed prospecting. For 1:1 personalized replies outside of a sequence, the link is optional; matching the tone of legitimate sales conversation is more important than blanket link inclusion.
CAN-SPAM and GDPR reality
US cold email under CAN-SPAM requires a functional unsubscribe mechanism, a physical postal address, and a truthful From header. Mailshake supports all three but does not enforce them; the sender is responsible for enabling the link and configuring the address. For EU prospecting, GDPR generally requires prior consent, and unsubscribe links do not create consent. Mailshake does not gate sends by geography, so senders bear compliance responsibility. Segmenting outreach by jurisdiction is standard practice for teams that operate internationally.
RFC 8058 headers on sequence sends
Mailshake adds RFC 8058 one-click unsubscribe headers on sequence sends from authenticated mailboxes. Each connected mailbox (typically Gmail, Outlook, or a custom SMTP server) must have DKIM configured; Mailshake can help set this up through the mailbox connection flow. The List-Unsubscribe and List-Unsubscribe-Post headers are added automatically for teams sending significant volume to Gmail or Yahoo, satisfying the February 2024 bulk-sender enforcement rules.
Suppression list and team coordination
Mailshake maintains an account-wide suppression list that blocks further sequence sends to any prospect who unsubscribes or replies unfavorably. This suppression persists across sequences, campaigns, and team members, preventing another rep from accidentally re-approaching a prospect who has already opted out. The suppression list is exposed through the Mailshake API for reconciliation with external CRM systems (Salesforce, HubSpot), which is essential for teams operating multiple prospecting tools in parallel.
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.
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