Unlimited SMTP server: run your own on a VPS
An unlimited SMTP server has no per-email fee and no volume cap from the software. Many "unlimited SMTP" plans are shared or hosted servers with hourly limits in the small print. With TurboMTA you run your own SMTP server on a VPS or PC, send from your own IPs and pay once per server.
Hosted "unlimited SMTP" versus your own SMTP server
| Topic | Hosted unlimited SMTP plan | Your own SMTP server (TurboMTA) |
|---|---|---|
| Who runs the server | The provider | You, on a VPS or PC you control (free setup included) |
| "Unlimited" in practice | Often subject to hourly caps, recipient limits and fair-use terms; read the contract | No cap in the software; limited by hardware, IP reputation and your host's rules |
| IP addresses | Usually shared or rotated by the provider | Your own IPs, which you warm up and protect |
| Cost model | Monthly fee | One-time licence per server plus your VPS cost |
| Data and logs | On the provider's servers | On your servers |
| Start-up effort | Minutes: paste credentials | A day or more: DNS, install, warm-up (we help) |
Searching for an unlimited SMTP server usually turns up two different things. One is a hosted plan where a company gives you SMTP credentials on its servers. The other is software that turns a server you control into an SMTP server. They solve the same need differently. SendUnlimitedMail sells the second kind: TurboMTA, software you run yourself. We do not sell SMTP credentials or hosting.
What to check before you buy any "unlimited" SMTP plan
- Hourly or daily sending caps and recipients-per-message limits.
- Whether IPs are shared, and what happens when another customer damages their reputation.
- The suspension policy and what counts as abuse or a complaint.
- Whether it allows your kind of mail: marketing, transactional or both.
- Claims of guaranteed inbox delivery: nobody can promise that, so treat them as a warning sign.
What you get with TurboMTA
TurboMTA is a self-hosted mail server (MTA) written in Go for Linux and Windows. It gives your VPS everything an SMTP server needs for sending:
- SMTP on ports 25, 587 and 465 with SMTP AUTH and STARTTLS, plus a native REST API.
- DKIM signing with several selectors per domain.
- VirtualMTA IP pools for per-domain routing and rotation across IPs you own or rent.
- Per-domain rate limits and backoff on bounces, so each mailbox provider gets a pace it accepts.
- A real-time web dashboard for queue, deliveries, bounces and suppression.
Connect your applications
Any application that accepts a custom SMTP server can send through TurboMTA. Create an SMTP user, then enter your own values. Example settings for a Laravel app (replace the placeholders):
- MAIL_HOST=mail.example.com
- MAIL_PORT=587 and MAIL_ENCRYPTION=tls (STARTTLS), or port 465 for implicit TLS.
- MAIL_USERNAME and MAIL_PASSWORD: the SMTP user you created in TurboMTA.
- The From address must use a domain with SPF, DKIM and DMARC in place.
How much can it send?
There is no single number, and anyone who gives you one without knowing your server and reputation is guessing. Throughput depends on CPU, RAM and network, on how many warmed-up IPs you use, on the pace each mailbox provider accepts, and on how recipients react. We recommend at least 2 GB of RAM and a gradual warm-up.
Who it is for, and the rules
TurboMTA is built for permission-based sending: newsletters and product mail to people who opted in, and transactional mail from your own applications. Our acceptable-use policy prohibits spam, purchased or scraped lists and phishing, and breaking it ends support.
Next steps
- Turn a VPS into an email server: Six steps with the exact DNS records.
- SMTP server for MailWizz, Acelle and Mautic: Connect your campaign software.
- What unlimited sending really means: The four real limits and a cost model.
- Pricing: $249 Linux, $249 Windows, $299 bundle, one-time.
Frequently asked questions
Is "unlimited SMTP" hosting really unlimited?
Often not. Hosted unlimited SMTP plans usually add hourly sending caps, recipient limits per message, shared IPs and fair-use rules in the small print. Read the terms for hourly limits, suspension policy and IP sharing. Running your own SMTP server removes the vendor cap, but your hardware and IP reputation still set the real limit.
Can I use TurboMTA as the SMTP server for MailWizz, Acelle, Mautic or my own app?
Yes, any application that lets you add a custom SMTP delivery server can send through TurboMTA: create an SMTP user, then enter your mail hostname, port 587 (STARTTLS) or 465, and the credentials. These are generic SMTP settings, not certified integrations, so check your application's own documentation for bounce handling.
Do I need an SMTP relay or can I send directly from my VPS?
You can send directly if your VPS provider allows outbound port 25 and you set up reverse DNS, SPF, DKIM and DMARC. If port 25 is blocked and cannot be unblocked, you either change provider or relay through another service on port 587 or 465. TurboMTA works for both.