Limits & fair use

Real correspondence. You and the people you write to. Personal mail, project mail, small business mail. That’s the whole product, and keeping it to that is exactly why your mail lands in inboxes instead of spam folders.

Every MailHow mailbox sends from the same small set of IP addresses, and every inbox provider judges those addresses by the worst mail that leaves them. One account blasting a list would cost everyone else their delivery. That is the entire reason these numbers exist. They are not a paywall: the paid plan doesn’t raise them, and we don’t sell a bigger tier.

They are sized for correspondence, which is what this product is. If you write a hundred messages in an hour you are having an unusually busy day; if you need to send thousands, you need a bulk sender, and we would rather say so than take your money and fail you.

• Up to 100 messages per hour, per mailbox.
• Up to 500 messages queued at once, per mailbox.
• Around 40 MB per message, attachments included. This is the message size limit, not your storage.
• Mailbox storage: 1 GB on the free tier, 10 GB on the paid plan.

Approaching a limit, you’ll get a heads-up. Going over briefly, we’ll slow you down (defer), never bounce your mail. A deferred message keeps retrying and gets through; a bounced one is lost.

To protect the shared sending reputation, MailHow is not for:

• Spam or any unsolicited email.
• Marketing, advertising, or promotional bulk email.
• Running a mailing list or newsletter blast. (Subscribing to and replying to lists is fine.)
• “Warming up” a domain or sending reputation. There are dedicated services for that; we are not one.
• Phishing, malware, or anything illegal.

Light transactional mail to your own customers (receipts, confirmations) within the limits above is fine. If you need to send at volume, use a dedicated bulk/transactional provider, that’s a different job than a mailbox.

We watch the signals that show abuse in progress: per-account sending rates, bounce and complaint rates, the feedback loops inbox providers give us, and reports sent to abuse@mailhow.com. Accounts that endanger the platform or other users’ deliverability can be suspended immediately, and serious violations of these terms can lead to termination without refund. On a shared platform, one abuser hurts everyone. So we’re strict about this on purpose. Full terms are in the Terms of Service.