Cutter 8
$ 34 /month
- vCPU
- 4 × dedicated
- RAM
- 8 GB
- Storage
- 160 GB NVMe SSD
- Transfer
- 10 TB
- IPv4 / IPv6
- 1 / /64 routed
Solution
VPS for a self-hosted mail server (Postfix, Mailcow, Stalwart)
Cutter 8 · $34/moCutter 16 · $62/mo
Short answer
Self-hosting mail needs three things most providers do not give you: outbound port 25 open, self-service reverse DNS, and address space with no spam history. Two cores and 4 GB run Mailcow for a small team, 8 GB if you want full-text search. Deliverability, not hardware, is the hard part — set SPF, DKIM and DMARC before you send a single message.
What you need
| Resource | What you actually need |
|---|---|
| CPU | 2 cores for a small team, 4 for 50+ mailboxes |
| RAM | 4 GB minimum for Mailcow; 8 GB with Solr search |
| Disk | 160 GB NVMe and up, sized to your archive |
| Network | Port 25 outbound, static IPv4, self-service PTR |
Recommended plans
Cutter 16
$ 62 /month
- vCPU
- 6 × dedicated
- RAM
- 16 GB
- Storage
- 320 GB NVMe SSD
- Transfer
- 15 TB
- IPv4 / IPv6
- 1 / /64 routed
Recommended locations
Location is usually the decision that matters most for this workload — either because latency dominates, or because jurisdiction does.
Why OnionVPS for this
- Outbound port 25 is open by default — you do not have to ask, and there is no probation period.
- Reverse DNS is set from the panel in seconds; receivers reject mail without a matching PTR.
- Our IPv4 space is not recycled from previous abuse tenants, so you start with clean reputation.
- Swiss and Icelandic locations put stored mail under statutory correspondence protection.
How to set it up
-
Deploy a Cutter 8 and set the hostname
mail.example.com, matching what you will publish in DNS.
-
Set reverse DNS from the panel
The PTR record must resolve back to the same hostname or most receivers will reject you.
-
Install Mailcow or Stalwart
Both ship a complete stack; Stalwart is a single Rust binary if you prefer less Docker.
-
Publish SPF, DKIM and DMARC
Start DMARC at p=none, read the reports for a fortnight, then move to p=quarantine.
-
Warm the IP up gradually
A few dozen messages a day for the first week. Volume spikes from a new IP look exactly like a spam run.
Frequently asked questions
Is port 25 open on your VPS?
Yes, outbound port 25 is open on every instance by default. We do not require a support ticket, an account age, or a paid add-on to unblock it.
Can I set reverse DNS (PTR) myself?
Yes, for both IPv4 and IPv6, directly from the control panel. Changes propagate within a few minutes.
Will my mail land in spam?
Not if you configure SPF, DKIM, DMARC and a matching PTR, and warm the address up. Those four things account for the overwhelming majority of deliverability problems.