How to set up a cold email domain (secondary domains + redirects)
Never send cold email from your primary domain. Buy a few lookalike secondary domains, 301-redirect them to your main site, set up SPF/DKIM/DMARC, and warm them. Here's the full setup.
Short answer: to set up a cold email domain, don't use your primary domain — buy a few lookalike secondary domains (e.g. try-acme.com, getacme.io), 301-redirect them to your main site, configure SPF + DKIM + DMARC on each, add a couple of warmed mailboxes per domain, and warm them for ~3 weeks. This protects your primary domain's reputation while letting you scale volume across several domains.
The setup, step by step
- Buy 2–4 secondary domains that resemble your brand.
- 301-redirect each to your primary site (so clicks/lookups land somewhere real).
- Authenticate each: SPF, DKIM, DMARC (start
p=none). - Add 1–3 mailboxes per domain (Google/Microsoft/SMTP).
- Warm up ~21 days before real sends; cap each mailbox at 30–50/day.
- Rotate across the pool and watch bounces per mailbox.
Why a separate domain
If a cold campaign hits spam traps or complaints, you want the damage contained to a throwaway domain — not your main one that hosts your app and team email.
Autocloz manages the mailbox pool, warmup, auth checks and rotation across all your sending domains automatically.
> Start free — connect your sending domains and let Autocloz pace + protect them.