Posted on 21 April 2026

The Anti-Attachment Guide: Why Logo Attachments Hurt Deliverability

Using logo files as traditional email attachments in signatures can create hidden deliverability and usability issues. A better approach is to keep signature visuals remotely hosted and lightweight.

Why attachment-heavy signatures are problematic

• Spam and trust signals: repeated attachment patterns can increase filtering sensitivity in some environments.
• Data waste: repeatedly sending image binaries inflates message weight at scale.
• Gmail clipping risk: larger email payloads increase the chance of clipped content.
• User confusion: recipients may mistake decorative assets for actionable attachments.

The remote-loading alternative

Mirosign uses hosted signature assets so the message body stays cleaner while visuals remain on-brand. This helps teams keep signatures professional without attachment overhead.

Best-practice checklist

• Use optimized hosted images for signature graphics.
• Keep signature layouts concise and lightweight.
• Avoid unnecessary decorative files in every send.
• Test rendering across Gmail, Outlook, and mobile clients.

Start designing free and apply anti-attachment best practices from day one.

Read next

• The Signature School
• Email Signature Accessibility Guide
• No-Tracking Email Signatures