Anti-Spam Filters

What Are Anti-Spam Filters?

Anti-spam filters automatically mark unwanted emails as spam based on the sender’s address, domain, or subject. They work independently from filters — they are simpler and dedicated exclusively to spam protection.

Filter Types

An anti-spam filter can block emails based on:

• Sender email — a specific address (e.g., [email protected])
• Domain — all addresses from a given domain (e.g., spam-company.com)
• Subject — messages containing a specific phrase in the subject

You can combine conditions — e.g., an email from a specific domain and with a specific subject.

Per-User and Per-Account Filters

Anti-spam filters can operate at two levels:

• Per account — blocks spam for all users in the account
• Per user — blocks spam only for a specific user

Per-user filters have higher priority than per-account filters.

Creating an Anti-Spam Filter

1. Go to Mail → Anti-Spam Filters
2. Click + (New Filter)
3. Fill in:
   • Sender email — address to block
   • Domain — domain to block (alternative to email)
   • Subject — phrase in the subject
   • User — optionally, per-user filter
4. Save

An anti-spam filter can also be created directly from the email view — the Mark as Spam button automatically creates a filter.

Filter Priority

The system automatically calculates priority based on specificity:

1. Email + subject (highest)
2. Email
3. Domain + subject
4. Subject
5. Domain (lowest)

Spam Counter

Each filter has a counter showing how many emails it has blocked (spam_count).

Important Information

• Provide either email or domain — not both at the same time
• The sender email must be unique within the account/user scope
• Per-user filters take priority over per-account filters