VPSGrid Port 25 Outbound SMTP Policy

Outbound port 25 is blocked by default to prevent spam abuse. Use SMTP relays (587/465 with auth) for app mail. Port 25 exceptions require review — not guaranteed.

Overview

VPSGrid restricts outbound TCP port 25 on VPS instances by default. This protects IP reputation for all customers and aligns with industry anti-abuse practice on unmanaged hosting.

What this means

• Direct MTA-to-MTA delivery on port 25 from your VPS is blocked by default
• Application mail should use an authenticated relay (SendGrid, Mailgun, Amazon SES, etc.) on ports 587 or 465
• WordPress, cron, and app mail() functions need relay plugins or SMTP configuration — not raw port 25

Recommended approach

1. Choose a transactional email provider with API or SMTP auth
2. Configure your app to send through the provider — not localhost:25
3. Monitor bounce/complaint rates — compromised apps cause abuse suspensions

Port 25 review requests

If you believe your use case requires outbound port 25, open a billing/support ticket describing:

• Business identity and mail volume
• Opt-in list practices and bounce handling
• Why relay services cannot meet the requirement

VPSGrid does not guarantee port 25 approval. Confirmed spam or abuse leads to suspension per Abuse Policy.

Related ports

See Common VPS Port Numbers for SSH, HTTP, HTTPS, and RDP reference.

Verify

1. Application sends via authenticated relay — test message received
2. No reliance on localhost port 25 for production mail

Frequently Asked Questions

Related Articles

• Common VPS Port Numbers
• Article 6.2 — VPS Grid Abuse Policy
• Security Responsibilities on Unmanaged VPS
• What Information to Include in a Support Request

Need More Help?

Search this knowledgebase for related guides. If the issue persists, open a ticket at billing.vpsgrid.net with your service ID, primary IP, and steps already tried. See What Information to Include in a Support Request and Security Responsibilities on Unmanaged VPS for scope and required details.