Default Headers for Dedicated Sending Domains

A “default header” provides a fallback From Name and From Email for outbound messages sent via a dedicated sending domain when DMARC alignment fails. This ensures deliverability and brand consistency, even if a campaign’s custom header does not match the authenticated domain.

TABLE OF CONTENTS

• When to Use Default Headers
• Prerequisites
• Setting Default Headers (From Name & From Email)
• How Default Headers Work in Practice
• Best Practices & Considerations
• Common Troubleshooting Scenarios

When to Use Default Headers

• Fallback for DMARC Failures: If a campaign’s “From” address does not align with your dedicated sending domain’s DKIM/SPF records, HighLevel will automatically switch to the configured default header so that the message is still authenticated.
  
  

• Maintain Consistent Branding: Even if a typo or misconfiguration causes a non-aligned “From,” recipients will see your brand’s domain in the From field rather than a rejected address.
  
  

• Regulatory/Compliance Requirements: Industries requiring strict email authentication (finance, healthcare, etc.) should configure default headers to avoid DMARC rejections or quarantines.

Prerequisites

Before you can configure default headers, ensure that:

1. You’re in a Sub-Account

   • Only sub-accounts can add and manage dedicated sending domains and set default headers. Agency-level domains do not support per-sub-account default headers.
     
     

2. Dedicated Sending Domain Is Added and Validated

   • You have completed DNS setup (CNAME, DKIM, and SPF) for your custom sending domain (e.g., email.yourbrand.com).
     
     

   • HighLevel displays a green checkmark indicating your domain is validated under Settings → Email Service → SMTP Service → Dedicated Domain and IP

Setting Default Headers (From Name & From Email)

Navigate to Sub-account Settings - Email Service -> SMTP Service -> Dedicated Domain and IP -> Set headers under dedicated domain.

The designated header will be applied to emails sent through the dedicated domain when DMARC alignment fails.

How Default Headers Work in Practice

1. Campaign Configuration

   • When creating a broadcast or workflow email, you can set a campaign-level “From Name” and “From Email.”

   • If you intentionally use a different “From Email” (e.g., [email protected]) that does not align with your dedicated domain (email.yourbrand.com), DMARC will fail.

2. DMARC Check & Fallback

   • At send time, HighLevel checks DMARC alignment between the campaign’s “From” address and the sending domain’s DKIM/SPF records.

   • If alignment passes: The email goes out with the campaign’s chosen “From.”

   • If alignment fails: HighLevel overrides the campaign’s “From” with the default header you configured under that dedicated domain.

3. Recipient Experience

   • Recipients see a valid “From Name” and “From Email” that matches your authenticated sending domain.

   • The email remains DMARC-compliant and is less likely to be rejected or flagged as spam.

Best Practices & Considerations

1. Configure Default Headers Before Sending: Always set up your fallback header prior to launching major campaigns. If DNS or DMARC misconfiguration occurs, your default header will kick in automatically.
   
   

2. Monitor Replies: The default “From Email” can be any address at your sending domain, but ensure mailboxes or aliases are monitored (e.g., [email protected] forwarding to the correct team).
   
   

3. Test Before Scaling: Send a small internal test using a non-aligned “From” address to confirm HighLevel defaults properly. Check both inbox placement and DMARC status.
   
   

4. Understand Propagation Delays: Changing DNS (especially DKIM/SPF/TXT records) can take up to 48 hours to fully propagate. Without default headers, messages sent during propagation may be rejected.
   
   

5. Segregate by Sub-Account: If you manage multiple brands or departments, create separate sub-accounts—each with its own dedicated domain and default headers—for isolated control.

Common Troubleshooting Scenarios