Deliverability Comes Before Copy
I see it constantly. A founder spends two weeks perfecting their cold email copy, loads up 5,000 leads, hits send from their main company domain, and gets a 0.5% reply rate. They conclude that cold email is dead.
Cold email is not dead. Their emails just never reached a human being. They went straight to spam, and no amount of clever copywriting can save an email that nobody sees.
Across the client campaigns we run, the single biggest driver of results is not the messaging. It is whether the sending infrastructure was built properly before the first email went out. Get this right and average copy will still book meetings. Get it wrong and world-class copy will book nothing.
Here is the exact setup we use for every client.
Step 1: Never Send Cold Email From Your Main Domain
Your primary domain carries your company's entire email reputation. Client conversations, invoices, support threads, everything. If that domain gets flagged for spam, your real business email starts landing in junk folders, and repairing a burned domain takes months.
So the first rule is simple: cold outbound never touches your main domain. Instead, buy secondary domains that are close variations of your brand. If your company is acme.com, you might pick tryacme.com, acmehq.com, and getacme.com.
Two things matter when choosing them. First, they should look credible to a prospect who glances at the sender address. Second, every secondary domain must redirect to your real website, so anyone who types it into a browser lands on your actual site instead of a blank page. A parked, empty domain is a spam signal to both filters and humans.
Step 2: Structure Your Mailboxes for Volume
The math of cold email volume is mailbox math. A healthy mailbox can send roughly 20 to 30 cold emails per day before providers start paying attention. If you want to send 300 emails a day, you do not push one mailbox harder; you spread the load across more mailboxes.
Our standard pattern is 2 to 3 mailboxes per domain, usually simple name variations like des@ and des.l@ on each one. Keep it to a real human name. Mailboxes like info@, sales@, or outreach@ get worse inbox placement and worse reply rates because they scream mass email.
A typical starting setup for a client looks like this:
- 3 to 5 secondary domains
- 2 to 3 mailboxes per domain
- 20 to 30 cold emails per mailbox per day once warmed
That gives you somewhere between 200 and 400 emails per day of safe capacity, which is more than enough to book meetings consistently. It also gives you insurance: if one domain takes a reputation hit, you pause it and the rest of the system keeps running.
Step 3: Get Your DNS Records Right
Every sending domain needs three DNS records configured before it sends anything: SPF, DKIM, and DMARC. These records prove to receiving mail servers that you are who you say you are.
You do not need to understand the cryptography behind them. You need to know that Google and Microsoft now effectively require all three for bulk senders, and a missing record is one of the fastest routes to the spam folder. Most modern mailbox providers set these up for you automatically or give you the exact records to paste in. Verify all three on every domain before warmup starts, not after a campaign underperforms.
Step 4: Warm Up Before You Send
A brand new mailbox has zero reputation. If it starts blasting 30 cold emails a day in its first week, providers treat it exactly like what it looks like: a spam operation spinning up fresh accounts.
Warmup fixes this by having your mailboxes exchange emails with a network of real inboxes that open, reply to, and rescue your messages from spam. This gradually builds a history of positive engagement.
Our rules for warmup:
- Warm every new mailbox for at least 2 to 3 weeks before it sends a single cold email
- Ramp sending volume gradually instead of jumping straight to full capacity
- Keep warmup running in the background permanently, even on active mailboxes
Skipping warmup to launch a week earlier is the most expensive shortcut in cold email. You save seven days and lose the domain.
Step 5: Respect the Limits Once You're Live
Infrastructure is not a set-and-forget asset. It degrades if you abuse it. The operating rules we hold every campaign to:
- Stay at or under 30 cold sends per mailbox per day
- Keep bounce rates under 3% by only emailing verified addresses
- Rotate sending across all mailboxes instead of leaning on one
- Remove unsubscribes and bounces from your lists immediately
Bounce rate is the one to watch most closely. Every bounced email tells the receiving server that you are guessing at addresses, and a bounce rate above 4 or 5% can tank a domain in days. This is why lead verification is not optional, and it is why we prune unverified emails from every list before a campaign launches.
Watch the Signals
You will know your infrastructure is healthy by watching a few numbers weekly. Open rates holding steady, reply rates in the normal range for your offer, bounces under 3%. When something is wrong, the pattern is usually a sudden cliff: opens drop by half overnight on one domain. When that happens, pause that domain, let warmup run on it for a couple of weeks, and shift volume to your healthy domains. This is exactly why you built more capacity than you need.
None of this is glamorous. But this unglamorous foundation is the difference between a campaign that books 7 qualified meetings a week and one that quietly emails a spam folder for a month. Build the foundation first, then worry about the copy.
If you have questions about your own setup, feel free to reach out. I am happy to take a look.