A small VPS costs about the same as a cheap email plan, and open-source mail servers have never been easier to install. For 5 to 20 users the server is the easy part. Here is everything else, so you can decide with the whole bill in front of you.
The short answer
Run your own server if you want to learn mail and can watch it every week. Pay a host if the mail belongs to a business and nobody wants that job. The VPS is cheap; the hours, the blocked ports and the first month of reputation-building are not.
- Typical VPS: About $5 to $6 a month
- Flat hosted plan: $5 to $6 a month for unlimited mailboxes
- Port 25 at big clouds: Blocked or throttled by default
- Ongoing time: An hour or two a month when nothing breaks
The first wall: port 25
Servers deliver mail to each other on port 25, and the big clouds close it by default because new accounts are where spam comes from. Google Cloud blocks outbound port 25 on every VM and does not lift it. AWS throttles it on EC2 until you file a request to remove email sending limits. DigitalOcean blocks SMTP ports on Droplets, and its documentation recommends a third-party sending service instead. Hetzner keeps port 25 closed on new cloud accounts and considers an unblock request once you have been a paying customer for about a month.
The usual fix is to send through a relay service while the server receives directly. That works well, and it also means you now have two providers, two bills and two sets of DNS records to keep aligned.
What Gmail checks before it accepts your mail
- SPF or DKIM on the sending domain (both, plus DMARC, at 5,000 a day)
- A PTR record: the IP's reverse DNS must match a name that points back to it
- TLS on the connection
- A spam complaint rate under 0.3% in Postmaster Tools
- An IP address that is not on a blocklist from its previous tenant
- Some history, because a brand new IP is treated with suspicion
The first four are configuration, and a good install script handles them in an afternoon. The last two are not under your control. A VPS address is recycled from whoever had it before, and if they sent spam you inherit the listing. Even a clean address starts with no reputation, so the first weeks can mean mail to Gmail and Outlook landing in spam while the address builds history. Gmail's rejections say which rule failed: 550 5.7.25 for a missing PTR, 550 5.7.26 for unauthenticated mail.
The real bill for 5 to 20 users
| Own server on a VPS | Flat hosted plan | |
|---|---|---|
| Monthly cost | $5 to $6 for the VPS, more for storage and backups | $5 to $6 for unlimited mailboxes |
| Outgoing mail | Direct once port 25 is open, or through a paid relay | Included |
| Spam filtering | Yours to tune | Included |
| Backups | Yours to set up and test | The host's job |
| Updates and security patches | Yours, every month | The host's job |
| When mail stops at 2 a.m. | You | Support |
| Your time | A day to set up, an hour or two a month after | An hour to set up |
Flat hosted plans at this price: Faivelo Starter $6 a month ($5 yearly), MXroute from $59 a year, Purelymail $10 a year. Prices checked 6 October 2026.
At 5 to 20 users the money is roughly even. The difference is who carries the pager. If one of those users is your best customer and their invoice bounces, an hour of your time is worth more than a year of hosting.
When running your own server is the right call
If you want to understand email properly, nothing teaches it like running a server. It is also right when your data has to stay on hardware you control, or when you already run infrastructure and have monitoring and backups in place. Mature open-source servers and all-in-one installers make the setup far less painful than it was ten years ago.
If none of those is true, a flat hosted plan costs the same and leaves the hard parts to someone whose full-time job they are. On Faivelo that includes placing the DNS records at your registrar for you and copying your existing mail in over IMAP. The record values are the same ones described above; the difference is that we keep checking them. For what a host does day to day, see what email hosting is.
The server costs five dollars. The reputation, the patches and the 2 a.m. bounce are the rest of the bill.
FAQs
Can I receive on my own server and send through a relay?
Yes, and it is the common way around a blocked port 25. Add the relay to your SPF record and publish its DKIM key, so mail sent through it still authenticates as your domain.
Is a home connection an option?
Rarely. Most residential connections block port 25 and their IP ranges are on lists that big mailbox providers reject or filter.
How long does a new mail server IP take to build reputation?
There is no fixed number. Start with low, steady volume to people who expect your mail, watch Postmaster Tools, and expect a few weeks before results settle.
Can I move from my own server to a host later?
Yes. Copy the mailboxes over IMAP, switch the MX and authentication records, and copy again to catch the stragglers. Nothing about the addresses changes.
Keep the domain, skip the server
Unlimited mailboxes for $6 a month, DNS placed for you, and your existing mail copied in. Fourteen days free, no card.