How many mailboxes you need, and why month one is short.

Everyone sizes their infrastructure off the steady state and then wonders why the first month missed. A new mailbox does not start at twenty five a day. This shows you both numbers.

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Twenty two working days a month, a hard ceiling of twenty five a day per mailbox, three mailboxes to a domain. Those three are not settings. Everything else on this page follows from them.

The arithmetic

Mailboxes you need

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Mailboxes, a month {{total}}

That is what your mail provider charges, not what Hisendy charges. Every Hisendy plan takes as many Google and Microsoft mailboxes as you want to connect, including the $29 one.

The three numbers everyone gets wrong.

Twenty five a day, not fifty Fifty a day from one mailbox is the number sold on landing pages. It is also the number that gets a domain filtered inside a fortnight. Twenty five is the ceiling here and it does not move, whatever plan you are on.

Three mailboxes a domain Put twelve mailboxes on one domain and the domain carries all twelve reputations at once. Three is the convention because when one goes wrong you lose a third of your capacity, not all of it.

Month one is 62 per cent of month two A mailbox that starts at eight a day and reaches twenty five in five weeks sends 340 in its first month and 550 after that. Size for the steady state and month one misses. Size for month one and you are paying for idle mailboxes forever. Most people should take the slower month.

The other free tools

List cleaner Paste a list. Get back the addresses worth paying to verify. Open it SPF, DKIM and DMARC checker Read your records the way a receiving server reads them. Open it Credit calculator Every AI action, priced, before you hand over a card. Open it

You can count mailboxes yourself. Pacing them is the work.

Connect as many as you like. Hisendy holds each new one at 8 a day, walks it to 25, and never asks you to run a warmup pool.

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No card. 2 mailboxes, 100 sends and 100 AI credits to start.