Choosing an SMTP mailbox service when you are still testing outreach

Count the people who will genuinely send from their own address during your test, not the size of the list you hope to reach. That headcount is the figure that decides your tier. A startup running a small honest test usually needs fewer mailboxes than it assumes, because most of the work sits with one or two people writing and following up.

Lifetime tiers sized by mailbox count mean the number you commit to is a mailbox number, not a monthly send allowance. Before you pay, write down who needs an address, which replies route where, and whether anyone outside the founding group will send. If the answer is uncertain, the smaller tier keeps the test bounded while you learn whether outreach produces replies at all.

The figure that should not drive your choice is the size of your prospect list. A mailbox is not a contact list, and no tier supplies recipients, so the names you write to are your own research either way. Compare tiers on seats you will actually configure and check, and treat list building as separate work with its own cost in time.

Each lifetime level hands you a set number of mailboxes: Starter covers five, Studio covers fifteen, and Floor covers fifty. Those are the published tiers, and the mailbox count is the variable that separates them. Everything the product provides around a mailbox, including browser webmail and the warm-up and authentication checks, applies to the mailboxes you hold at your level.

For a small founding team, five mailboxes is often enough to test whether cold outreach earns replies: one or two sender addresses, a shared address for inbound, and room for a co-founder. Fifteen suits a team that has added a second sender or split outreach by segment. Fifty is a commitment to scale, and it makes sense once replies already exist and you are adding senders deliberately.

What you get at every level is the same kind of working mailbox: standard SMTP and IMAP, accessible in a browser as well as a mail client, with warm-up and authentication checks alongside setup. What changes is how many of those mailboxes you hold. That distinction matters because the product's job is to give you addresses you control, not to fill your pipeline.

Behind the tier comparison sits a simpler question: is outreach worth doing at all for your startup right now? If you cannot say who you would write to and what you would ask, no mailbox tier fixes that. Answer the question first, then choose a tier that lets you test the answer cheaply rather than one that assumes the answer is yes.

Your biggest objection, an annual contract signed before the first reply, is a fair one. Lifetime tiers avoid the recurring commitment question, but they still ask you to choose a mailbox count up front. The sensible approach is to pick the level that matches the test you can honestly run in the next few weeks, not the level that matches your ambition for the year.

Ask also what happens if the test fails. A smaller tier leaves you with mailboxes you can still use for support, transactional mail or internal communication, so the spend is not wasted on an experiment that ended. If the test succeeds, moving up later is a decision made with evidence rather than hope. That sequence is the real comparison point between levels.

Moving from Starter to Studio buys ten more mailboxes, which means more senders, more inbound addresses, or both. For a startup, that step is usually justified by a second person owning outreach, or by splitting sender identity so replies land in the right place. It is not justified by a larger list, because the list comes from your own research regardless of tier.

Studio to Floor buys thirty-five more mailboxes and signals a different stage: outreach is producing replies and you are adding senders on purpose. At that point the work shifts from proving the channel to managing who sends what from which address. Buy the higher tier when that management problem is real, not in anticipation of it.

Across every step, the extra mailboxes come with the same underlying setup checks, and placement in the inbox is still not promised, so a message can miss it even when authentication passes. Services beyond the mailbox count carry their own price. Read the published table before paying so you know what your chosen level includes and what it does not.