Emails from my VPS go to spam

What this is#

Your VPS sends mail, but it lands in spam folders, or bounces outright. Deliverability comes down to three things receivers check: identity (does DNS prove who you are), reputation (does your IP and domain have a history), and content. Almost all of it is diagnosable and fixable yourself, and this page starts with the tools that tell you exactly what's wrong, faster than any support ticket could.

First, the ground rule: this guide is for the mail that's allowed on our network, personal, team, and transactional sending. If your volume is real, the honest fix is at the bottom.

Diagnose it in five minutes (before anything else)#

Three free tools pinpoint the problem, use them in this order:

1. mail-tester.com, the single best test. It gives you a one-time address; send a message to it from your VPS the same way your app sends, and you get a score out of 10 with an itemized list of everything wrong: missing SPF, broken DKIM, absent rDNS, blocklist hits, content flags. Fix what it lists, retest.
2. Gmail's "Show original", if Gmail is where your mail lands in spam. Open the message → three-dot menu → Show original: the top block shows SPF: PASS/FAIL, DKIM: PASS/FAIL, DMARC: PASS/FAIL for your actual mail. Anything not PASS is your to-do list.
3. MXToolbox, check whether your VPS IP and your domain sit on any blocklist, and use its SPF/DKIM/DMARC lookups to verify the records you publish. (Sending serious Gmail volume? Google Postmaster Tools shows your reputation with them directly. For an interactive walk-through of how your records evaluate, learndmarc.com is excellent.)

The foundation: your identity must line up#

Receivers first check that the sending server is who it claims to be. Three names must agree:

• Your mail server's hostname (what it says in the SMTP HELO, e.g. mail.yourdomain.com),
• the reverse DNS (PTR) of your VPS IP, set it yourself from the Network tab to that same hostname,
• and the A record of that hostname pointing back at your VPS IP.

That loop (forward-confirmed reverse DNS) is table stakes: without it, many receivers junk or refuse your mail no matter what else is right.

The authentication trio#

All three are DNS records at wherever your domain's DNS lives:

• SPF, a TXT record on your domain declaring which IPs may send for it: v=spf1 a mx ip4:YOUR.VPS.IP ~all. One SPF record only, multiple ones break validation.
• DKIM, your server signs outgoing mail and you publish the public key as a TXT record. Your mail stack generates the key pair (Mailcow does it for you; on plain Postfix, opendkim or rspamd does), and mail-tester tells you whether the signature verifies.
• DMARC, a TXT record at _dmarc.yourdomain.com telling receivers what to do when SPF/DKIM fail and where to send reports: start with v=DMARC1; p=none; rua=mailto:[email protected], and tighten to p=quarantine once reports show your legitimate mail passing.

Gmail and the other large receivers now effectively require SPF and DKIM, with DMARC strongly weighted. With all three passing plus correct rDNS, you're ahead of most of the internet.

Reputation: the part that takes time#

• A fresh IP has no history, and no history reads as suspicious. Warm it up: modest volume to real recipients who read the mail, ramping over weeks, not hundreds of messages on day one.
• Check the blocklists (MXToolbox above). If your IP is listed, the blocklist's own site has a self-service delisting flow, and fix the cause first or you'll be relisted. Keeping our ranges clean is exactly why bulk mail is forbidden here, which works in your favor: you're sending from a neighborhood that's kept clean.
• Rejected outright rather than spam-foldered? Read the bounce, the 550-style message names the reason and usually links the receiver's policy page (Gmail and Outlook bounces literally tell you what to fix).

Content, briefly#

With identity and reputation right, content rarely decides alone. The quick hygiene: send real text (not one big image), skip URL shorteners, make sure links point where they say, and keep your test phrases out of production mail (mail-tester flags the specifics for you).

When the right answer is a sending service#

If you're sending beyond personal and transactional volume, newsletters, campaigns, anything list-shaped, stop fighting deliverability from a single VPS: it's not allowed on our network, and services like Amazon SES or Mailgun exist precisely to own reputation and deliverability for you, cheaply. Many setups land on the hybrid: the VPS sends its transactional mail, the volume goes through a service.

When to contact us#

Almost everything above is self-service, the exceptions worth a ticket: outbound SMTP suddenly stopped working (our monitors block SMTP on mass-mail emission, fix the cause, often a compromised site or form, then ask for a review), or an rDNS record that won't apply from the Network tab.

Related questions#

• "Why do emails from my VPS go to spam?"
• "How do I test my email deliverability?"
• "How do I set up SPF, DKIM, and DMARC for my VPS?"
• "What reverse DNS do I need for a mail server?"
• "How do I check if my IP is blacklisted, and how do I delist it?"
• "Gmail rejects or junks my server's mail, what do I check?"