Quick answer
Protect deliverability by sending cold outbound only from dedicated sending domains, never your primary domain. Warm each inbox for three to four weeks, cap volume at roughly 30 to 50 sends per inbox per day, verify every address to keep bounces under 2 percent, authenticate with SPF, DKIM and DMARC, and remove anyone who does not engage.
Key takeaways
- Never send cold volume from your primary domain.
- Warm inboxes for three to four weeks before real volume.
- Keep bounce rate under 2 percent and spam complaints under 0.1 percent.
- Authenticate with SPF, DKIM and DMARC on every sending domain.
Setup checklist
- Register two to three lookalike sending domains, not your primary domain
- Configure SPF, DKIM and DMARC on each
- Create two to three mailboxes per domain
- Run automated warm-up for three to four weeks
- Verify every list before import and re-verify anything older than 60 days
- Cap at 30 to 50 cold sends per mailbox per day
- Include a plain-text opt-out and honour it immediately
Thresholds to watch
| Metric | Safe | Warning | Stop sending |
|---|---|---|---|
| Bounce rate | Under 2% | 2 - 4% | Over 4% |
| Spam complaints | Under 0.05% | 0.05 - 0.1% | Over 0.1% |
| Reply rate | Over 4% | 2 - 4% | Under 2% |
| Sends per mailbox / day | 30 - 50 | 50 - 80 | Over 80 |
Compliance basics
- United States: CAN-SPAM requires accurate headers, a physical address and a working opt-out.
- Canada: CASL requires consent or a documented existing business relationship. It is stricter than CAN-SPAM.
- United Kingdom and EU: UK GDPR and PECR apply. B2B cold email to corporate addresses is possible under legitimate interests, with documentation.
- Always suppress opt-outs globally and immediately, across every sending domain.
Frequently asked questions
Divide target daily volume by 40. For 400 daily sends, plan roughly ten warmed mailboxes across two to three domains.
It helps establish sending history, but list quality and reply rates matter more. Warm-up cannot rescue a bad list.
Talk to a Philippines outsourcing specialist
Tell us the role you need and we will send a shortlist of pre-vetted Filipino talent, a cost comparison against local hiring, and a 30-day onboarding plan.