Most business email is sold by the seat: one price per person, every month, forever. Flat-rate hosting charges one price for the account and lets you create as many addresses as you like. It is a small corner of the market, the hosts in it are very different from each other, and every flat price has fine print. This is the corner, mapped.
The short answer
Flat-rate email hosting means the bill does not change when you add a person or an address. Four hosts do it properly today, at very different prices and with very different limits, and the right one depends on who you are: a tinkerer with time, or a business with a team.
- Purelymail: $10 a year, no hard limits, advanced pricing if you use a lot
- Migadu: $19 a year for 5 GB with daily message caps, $90 a year for 30 GB
- MXroute: $59 a year for 10 GB, 400 emails an hour
- Faivelo: $6 a month for 10 GB and three domains, $12 for 200 GB and unlimited domains
What "flat rate" actually means
Per-seat hosting meters people. Flat-rate hosting meters something else instead: storage, messages per day, or messages per hour. That is the first thing to understand, because "unlimited mailboxes" never means "unlimited everything". The host has moved the meter from the one place that annoyed you to a place that, for most small businesses, never comes up. For a few businesses it comes up on day one, which is why the fine print below matters.
The four hosts here all sell real mailboxes on your own domain with IMAP and SMTP, all allow unlimited addresses, and all let you add more than one domain. After that they part ways.
Catch one: the storage pool
Flat plans come with a pool of storage shared across every mailbox, and the pool is the real price tier. Migadu Micro is $19 a year for 5 GB; Mini is $9 a month or $90 a year for 30 GB; Standard is $29 a month or $290 a year for 100 GB (migadu.com/pricing, checked 6 October 2026). MXroute Small is $59 a year for 10 GB, Medium $69 for 25 GB and Large $79 for 50 GB (mxroute.com, checked the same day). Faivelo Starter is $6 a month for 10 GB on up to three domains and Growth is $12 a month for 200 GB and unlimited domains. Purelymail is the odd one out: $10 a year with "no hard limits" on users, domains or storage, and a note that if you use significantly more than $10 a year in resources you may be moved to advanced pricing, which is a $4 a year account fee plus $0.56 per compressed gigabyte per year and small per-message rates (purelymail.com/pricing and purelymail.com/advancedpricing, checked the same day).
The question to ask is how much mail your whole company keeps, not how many people it has. Five people with tidy inboxes fit in 10 GB for years. One person who never deletes an attachment does not.
Catch two: daily and hourly caps
This is the one that surprises people. Migadu's plans carry message caps per day: Micro allows 200 incoming and 20 outgoing messages a day, Mini 1,000 in and 100 out, Standard 3,000 in and 500 out (migadu.com/pricing, checked 6 October 2026). Twenty outgoing messages a day is fine for a personal domain and a problem for a shop replying to customers. MXroute allows 400 emails an hour per account across every plan (mxroute.com, checked the same day), which is generous for people and tight for anything automated. Faivelo does not meter everyday mail from mailboxes on paid plans. The only stop is a runaway limit of 2,000 messages an hour per login, there to catch a script or a stolen password. Application mail has its own separate quota (3,000 transactional sends a month on Starter, 20,000 on Growth).
Read the cap next to the price, and read it as a cap on the busiest day, not the average one.
Catch three: who does the setup, and who answers
The indie flat-rate hosts are run by small teams and they assume you can paste DNS records, choose a DKIM selector and read a bounce. That is not a criticism; it is the deal that makes $10 a year possible. If you enjoy that work, or already do it for a living, you will be happy there. Faivelo's price buys the other deal. The records are written at your registrar for you where the registrar allows it (one click at Cloudflare, Vercel, Netlify and others, a pasted key at Porkbun, Gandi and more). The migration from your old host runs in the background, and there is a support team on the other end. The unlimited mailboxes fine print spells out exactly where Faivelo's own limits sit.
A flat price moves the meter rather than removing it. The good hosts tell you where they moved it.
Who each host suits
A tinkerer with a few personal domains and a tolerance for DNS: Purelymail or Migadu Micro, and honestly either is cheaper than anything else on this page by a wide margin. A developer who wants many domains and does not mind an hourly cap: MXroute. A business with a team, role addresses, phones to set up and no appetite for records: Faivelo at $6 a month, with the 14-day trial to confirm the setup really is one click at your registrar.
If you want the three indie hosts and Faivelo compared line by line, including first-year cost once setup time is counted, that is Faivelo vs Purelymail, Migadu and MXroute. For how flat rate compares with the per-seat suites most teams are leaving, see the compare page.
FAQs
Is flat-rate email hosting cheaper than Google Workspace?
From the second person onward, yes, by a lot. Google Workspace Business Starter is $7 per user a month on an annual commitment (workspace.google.com/pricing, checked 6 October 2026). Five people cost $420 a year there and $72 on Faivelo Starter.
Does unlimited mailboxes mean unlimited storage?
No. Every flat plan has a storage pool shared by all mailboxes, and the pool decides the price tier. Check the pool against how much mail your company keeps.
Can I send newsletters from a flat-rate host?
Not from the indie hosts, whose daily or hourly caps are built for people, not campaigns. Faivelo includes separate marketing quotas from the Growth plan, with opt-in lists only.
Why are the indie hosts so cheap?
Small teams, no sales staff, and customers who do their own DNS. It is a fair trade if you are that customer.
Can I move between flat-rate hosts later?
Yes. They all speak standard IMAP, so any migration tool can copy mailboxes from one to another, and your domain stays wherever it is registered.
Flat rate, with the setup done for you
Unlimited mailboxes on your domain for $6 a month, records written at your registrar, old mail copied over in the background. Try it for fourteen days without a card and keep it only if the whole team is on it by then.