Cold-Email Deliverability

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name: Cold Email Deliverability
description: Sets up and protects cold-outbound sending infrastructure - dedicated lookalike domains, SPF/DKIM/DMARC authentication, 2-4 week mailbox warm-up, 30-50 sends/day per-mailbox caps, and continuous bounce/complaint monitoring, with a runnable DNS audit script. Use when someone says "my emails are going to spam", "set up cold email infrastructure", "warm up a new domain", "configure SPF DKIM DMARC", "how many cold emails can I send per day", or "my domain got blacklisted". Do NOT use for protecting an opted-in marketing or transactional program on your primary domain - use email-deliverability instead; do NOT use for writing the email copy - use cold-email-craft instead; do NOT use for designing the multi-step cadence - use outreach-sequence-designer instead; do NOT use for sizing the list - use prospect-list-builder instead.
---

# Cold Email Deliverability

Deliverability is not a copywriting problem; it is an infrastructure and reputation problem. The single most expensive mistake in cold outbound is sending it from the primary corporate domain - one spam-trap hit or complaint spike and invoices, hiring emails, and the founder's replies all start landing in spam, and that damage is slow and painful to reverse. Treat cold sending as a blast radius to isolate on purpose: separate domains, separate mailboxes, conservative volume, relentless monitoring.

Mailbox providers (Gmail, Outlook) score the *sending identity* - domain + IP + behavioral signals like complaints, bounces, and engagement - not the cleverness of the subject line. Primary-inbox placement is earned by behaving like a real human correspondent at low volume. Good copy on a burned domain still lands in spam. Note the scope: cold outreach to people who never opted in. An opted-in newsletter or transactional program follows different rules (subdomains of the primary domain, higher warm-up ramps, sunset policies) - that is email-deliverability territory.

## Inputs to collect

- Target daily send volume (or monthly prospect goal ÷ ~20 business days).
- Primary corporate domain, and confirmation that it will NOT be used for cold sends.
- Existing sending domains, their age, and any prior reputation damage (blacklist history, complaint spikes).
- ESP/mailbox provider (Google Workspace, Microsoft 365) and any existing SPF includes on the sending domains.
- List source and whether addresses are verified. If unverified, stop - route through lead-enrichment first.
- Label any volume or list-quality figure the user estimates rather than measures as a guess.

## The workflow

1. **Isolate the blast radius - separate sending domains.** Never send cold from the primary domain (acme.com). Register lookalike domains (trygetacme.com, acme-team.com, getacme.io) dedicated to outbound. Redirect them (301) to the main site so they resolve. If one gets burned, pause and rotate it without touching corporate mail.

2. **Authenticate DNS - all three, or you are getting filtered.**