Anti-spam tools that run on your Mac can be useful, but if you have the chance, use the anti-spam features offered by your email provider. Not only does server-based filtering prove less taxing to your computer’s resources, but the anti-spam settings persist when you check your email on a different computer or mobile device. SpamSieve features include:

Offers customizable safelist and blocklist Works with IMAP, Exchange, and POP mail accounts Color coding indicates how spammy each message is Runs on your Mac and keeps spam off your iPhone and iPad Integrates with macOS Contacts app Notifies you only when you receive non-spam emails

A free trial is available. The paid version is $30. Spam Sieve v2.9.39 is compatible with OS X Lion (10.7) through macOS Catalina (10.15). POPFile v1.1.3f is a free download that is compatible with OS X Yosemite (10.10) through macOS Sierra (10.12). With SpamSweep, you can configure how often your accounts are filtered and set up a notification schedule. It supports IMAP accounts and has features for safelisting and customizing filtering rules. SpamSweep is a free download that is compatible with OS X Panther (10.3) through Mac OS X Snow Leopard (10.6). Spamfire is a free download that is compatible with OS X Tiger (10.4) and OS X Leopard (10.5).