Daily Sending Limits
WarmySender enforces multiple layers of sending limits to protect your deliverability:
Campaign-Level Limits:
- Daily send limit — Max emails per campaign per day (default: 100)
- Per-mailbox cap — Max sends from a single mailbox per campaign per day (default: 50)
- Per-prospect cap — Max emails to one prospect per day (default: 3)
- Per-prospect cooldown — Minimum hours between emails to the same prospect (default: 24)
Mailbox-Level Rate Limits:
- 2 emails per minute per mailbox
- 40 emails per hour per mailbox
- 500 emails per day per mailbox (hard cap across all campaigns)
Plan-Level Daily Limits:
- Free / Lite: 17 emails/day
- Pro: 333 emails/day
- Business: 1,667 emails/day
- Enterprise: 3,333 emails/day
- Ultimate: 10,000 emails/day
Provider-Level Limits:
- 30 emails per minute across all mailboxes on the same provider
- 600 per hour, 6,000 per day per provider
Domain-Level Limits:
- Per-recipient-domain caps prevent over-sending to any single company (e.g., max emails to @google.com per day)
Backoff System:
If any rate limit is hit, the system backs off: 1 minute → 5 minutes → 15 minutes → 1 hour. It resets after 30 successful sends within a 60-minute window.
Best Practice: Start with 20-30 emails/day per mailbox for new campaigns and increase gradually. Use multiple mailboxes to scale volume safely.