Cold email infrastructure that lands in the inbox

Why most cold email dies before it's read

Cold email rarely fails because of the copy. It fails on infrastructure: campaigns sent from the main company domain, missing or broken SPF, DKIM, and DMARC records, brand-new mailboxes blasting 200 sends on day one, and nobody watching bounce rates until the domain is already burned. Once a domain lands on a blacklist, no subject line can save it.

We've rebuilt this stack for dozens of clients — we currently manage 71 sending domains — and the pattern is always the same: fix the foundation first, then scale volume. Our own benchmark of what a broken system looks like: 350 emails sent for a single reply. A properly built system changes that math by an order of magnitude.

What we build

• Secondary sending domains — your primary domain never touches cold outreach, protecting the reputation your regular email depends on.
• Full DNS authentication — SPF, DKIM, and DMARC configured and verified on every domain, plus custom tracking domains so links don't look like a spammer's.
• Mailboxes and warmup — 2–3 mailboxes per domain, warmed for two to three weeks before a single prospect email goes out, with sending caps that ramp gradually.
• Sending platform setup — Instantly or Smartlead configured with inbox rotation, reply detection, and per-mailbox limits that respect provider tolerances.
• Sequence copy — three-to-five step sequences with personalization variables built in Clay from your enriched list, not mail-merge blasts.
• Ongoing deliverability ops — bounce and blacklist monitoring, placement checks, and volume adjustments every week, because deliverability is a practice, not a setup task.

How an engagement runs

Week one: domains purchased, DNS configured, mailboxes created, warmup started, and your ICP locked with a verified list build. Weeks two to three: copy written and approved while mailboxes finish warming. Week three onward: campaigns launch at conservative volume and scale on data — replies get routed into your CRM with automated follow-up, and many clients pair the email machine with an AI calling agent that works the same list from a second channel.

Not sure whether email is even your best first channel? Read our breakdown of cold email vs cold calling for B2B.

FAQ

How many sending domains do I need?

A useful rule: each domain holds 2–3 mailboxes, and each warmed mailbox sends 20–30 cold emails a day safely. To send 1,000 emails a day you're realistically running 12–15 domains. We size the fleet to your target volume and budget.

How long before replies start coming in?

Warmup takes two to three weeks before launch, and most campaigns see their first qualified replies within the first two weeks of sending. Treat the first 30 days as calibration: copy angles, segments, and volume all get tuned on real reply data.

Do you write the email copy too?

Yes. Sequences, subject lines, and personalization variables are included — written for your ICP and offer, then A/B tested after launch. You approve everything before it sends.