Email sending limits by provider (Gmail, Outlook, SMTP, SES)
Gmail Workspace caps ~2,000 recipients/day (far lower for cold), Outlook ~10,000 but throttles new senders hard, SES scales with reputation. For cold email, the safe cap is ~30–50/mailbox/day. Here's the table.
Short answer: provider *account* limits (Gmail Workspace ~2,000 recipients/day, Outlook ~10,000/day, Amazon SES scales with reputation) are far higher than what's safe for cold email. For cold outreach the real cap is ~30–50 emails per mailbox per day after warmup — driven by deliverability, not the provider's hard limit. Scale with more mailboxes, not a hotter one.
Provider hard limits (for context, not targets)
- Gmail / Workspace: ~2,000 external recipients/day (much lower while new).
- Outlook / Microsoft 365: ~10,000/day, but throttles new senders aggressively.
- SMTP relays / SES: scale with your sending reputation + approved quota.
The cap that actually matters for cold
30–50/mailbox/day post-warmup. Want 400/day? Use ~10 mailboxes and rotate. One mailbox at its provider max = flagged fast.
Autocloz enforces per-mailbox daily caps + min-gap pacing and rotates across your pool automatically.
> Start free — scale safely across a mailbox pool, not a single inbox.