Email infrastructure and deliverability

Infrastructure is the layer that carries an email, and it is not the sequencer job. Treating it as one is the most common reason a campaign dies quietly. Four decisions are made here, all before anyone writes a subject line. Never send cold from your main domain, because reputation damage is not something you undo by stopping, and that domain also carries your invoices and your password resets. Get SPF, DKIM and DMARC written correctly, which is most of what you are paying a provider to automate at the moment a domain is created. Buy enough mailboxes that no single one carries too much volume, and let deliverability decide that number rather than the invoice. And warm up before ramping, which means the honest answer to when can we start is in about three weeks. Pricing here is per mailbox per month, in the two to five dollar range depending on whether it sits on their own infrastructure, on Google or on Microsoft, with dedicated IPs an order of magnitude above that. A dedicated IP is a real decision rather than a default: on low volume, a shared pool is warmer than anything you can build alone. Buy the estate before the campaign, not the week it launches.

What you are actually buying here

When I buy infrastructure, I am not buying software in the usual sense. I am buying domains and mailboxes with the DNS already written, so that SPF, DKIM and DMARC exist correctly from the first minute. That is the whole job of a provider like Mailpool: supply the estate the sending runs on, and take the authentication work off my hands. Everything else, the sequencer, the copy, the list, sits on top of this layer and inherits its reputation.

How the mailbox choice changes the bill

The price depends on where the mailbox sits. On their own infrastructure with rotating IPs, a mailbox costs 2.60 dollars per month. On Google rotating IPs it is 3.40 dollars per month, and on Microsoft rotating IPs it is 4.30 dollars per month. That spread is the practical version of a question I ask on every setup: does this client need the mailbox to look like a Google or Microsoft seat, or is a provider-run mailbox enough for the volume involved? The answer changes the monthly bill on an estate of any real size, so I decide it before buying, not after.

What you buy	Monthly cost
Mailpool mailbox, their own infrastructure, rotating IPs	2.60 dollars
Google Workspace mailbox, Google rotating IPs	3.40 dollars
Microsoft 365 mailbox, Microsoft rotating IPs	4.30 dollars
Dedicated IP, IPs you do not share	170 dollars

When a dedicated IP earns its price

A dedicated IP costs 170 dollars per month, which puts it in a different category from everything else on this page. On low volume I do not buy one, because a shared pool carries warmth I cannot build alone at that scale. A dedicated IP makes sense once volume justifies it and I control what runs on it. The mistake I see is buying one by default and then sending too little through it, which leaves a cold IP doing worse work than a warm shared one would.

What to decide before the campaign exists

The order I work in: separate domain, mailboxes bought in enough numbers that no single one carries too much volume, authentication verified, warmup started, and only then the sequencer. The ramping and the mailbox-count logic are covered in the infrastructure decisions made before the first email, and the platform choice that sits on top of this layer is covered in the four questions that decide a cold email platform. Buy the estate first. A burned domain cannot be bought back.