Email Sending Limits

RemarkableCloud routes all outbound mail through MailChannels, a transactional email relay. This protects your server’s IP reputation and improves deliverability. This page explains the limits and how they work.

Default sending limits

Limit	Default
Emails per hour per domain	500
Emails per hour per cPanel account	300
Maximum message size	50 MB
Maximum recipients per message	100
Daily sending limit	No hard limit at RemarkableCloud level

These limits apply to outbound mail sent through the server’s local mail system (Exim → MailChannels). They do not apply to mail sent via external SMTP services (Mailchimp, SendGrid, etc.) configured directly in your application.

MailChannels relay

All outgoing mail from your server passes through MailChannels before delivery. MailChannels:

• Maintains high sender reputation across its IP pool
• Handles retry logic for temporarily unreachable mail servers
• Provides delivery feedback (bounces, deferrals) visible in Exim logs
• Filters outgoing spam: if an account is compromised and sending spam, MailChannels blocks it before it affects your reputation

Increasing sending limits

If you need to send bulk email (newsletters, transactional notifications at scale), the server’s built-in limits are not the right tool. Instead:

Use a dedicated email service:

• MailWizz: self-hosted, full-featured email marketing platform. Can be installed on a separate Cloud Cube and routed through Amazon SES or SMTP.
• Amazon SES: low cost, high volume. Configure your application to use SES SMTP directly.
• Mailchimp / Brevo / SendGrid: managed services for marketing email.

Sending thousands of marketing emails through a hosting server (even legitimately) risks getting your server IP blacklisted, which would affect all email from all domains on the server. Use a dedicated sending service for bulk email.

Checking your mail queue

If email is queuing up or not delivering:

# View current mail queue
exim -bp

# Count messages in queue
exim -bpc

# View details of a specific message
exim -Mvl MESSAGE_ID

# Force delivery of queued messages
exim -qf

Or in WHM: Email → Mail Queue Manager.