Email deliverability for cold outreach
The best message in the world earns nothing from the spam folder. Deliverability — whether your email actually reaches the inbox — is the quiet foundation under every outbound result. This guide covers the warm-up, limits, authentication, and habits that keep you in the inbox.
Why deliverability decides outbound
Mailbox providers like Google and Microsoft constantly judge your domain's reputation. Send high volume from a cold domain, get marked as spam, or email unengaged lists, and they quietly route your mail to the spam folder — where reply rates collapse. The teams that win outbound treat deliverability as a discipline, not an afterthought.
1. Warm up your domain
A new domain or inbox has no reputation. Warm it up by ramping volume gradually so providers learn to trust you. A structured ~25-day ramp — starting near 20 emails/day and climbing steadily — builds trust before you scale. Skip this and you'll spend months digging out of the spam folder.
Outpace includes automatic domain warm-up that throttles your sending to the ramp schedule, so you can't accidentally outrun your reputation.
2. Respect sending limits
More sends is not more pipeline. Even on a fully warmed domain, keep sequenced volume measured — most teams should stay under ~300 sequenced emails per day per inbox. If you need more reach, add inboxes or tighten your targeting rather than cranking volume on one domain.
3. Authenticate your domain
Set up SPF, DKIM, and DMARC records. These prove your mail is legitimately yours and are effectively required by major providers. Misconfigured authentication is one of the most common reasons good cold email lands in spam.
4. Build habits that protect the inbox
- Tighten your ICP — fewer, better-fit recipients means fewer spam complaints.
- Personalize every message so it reads like a person, not a blast.
- Remove bounces and unengaged contacts promptly.
- Honor unsubscribes immediately and make opting out easy.
- Watch reply and bounce rates as early warning signals, not vanity metrics.
Most of these come back to fit. If you haven't tightened your targeting yet, start with our ideal customer profile guide.
Frequently asked questions
How many cold emails can I send per day safely?
On a freshly warmed domain, ramp gradually — start around 20/day and increase over a few weeks. Even after a full warm-up, most teams should stay under ~300 sequenced emails per day per inbox to protect reply rate and reputation. Volume beyond that is where deliverability usually breaks.
What is domain warm-up and do I need it?
Domain warm-up is the process of gradually increasing sending volume on a new domain or inbox so mailbox providers learn to trust it. Yes — sending a high volume from a cold domain on day one is the fastest way to land in spam. A structured ramp over ~25 days establishes trust before you scale.
What email authentication records do I need?
Set up SPF, DKIM, and DMARC on your sending domain. These records prove your mail is legitimate and are effectively required by major mailbox providers. Missing or misconfigured authentication is one of the most common causes of cold email landing in spam.
How do I improve my cold email reply rate?
Reply rate and deliverability are linked. Tighten your ICP so you send to fewer, better-fit accounts; personalize each message; keep volume measured; and remove unengaged contacts. Relevance signals to mailbox providers that recipients want your mail, which protects the inbox you depend on.
Deliverability, handled automatically
Outpace builds in domain warm-up and sending limits so your cold outreach stays in the inbox — and your reply rate stays high.