Outreach OS

Multi-inbox campaigns that don't burn out sender reputation.

Round-robin sending, timezone windows, per-mailbox caps, and per-domain throttling — so 10,000 emails a day look like 10,000 individual conversations.

  • Blended warmup: real cold sends mixed with warmup traffic from day one so ramp-up is invisible to spam filters.
  • One-click A/B on subject, opener, or CTA — winners promote automatically.
  • Every send has RFC 8058 unsubscribe headers — Gmail bulk-sender safe.
Round-robin sending
Distribute volume across mailboxes to protect each sender's daily quota.
UTC + local windows
Send only during a lead's business hours, in their timezone.
Per-domain throttling
Automatic cool-down between messages to the same recipient domain.
Multi-step sequences
Follow-ups branch on reply, open, or click — no more manual ticks.
Bring your own SMTP
Hostinger, Google Workspace, Zoho, Fastmail, AWS SES — you own the mailbox.
Reputation-safe defaults
Warm-up ramp, bounce backoff, and suppression list enforced automatically.
Related

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