Spam prevention is not only about filters. Your habits decide how often your main address appears in forms, lists and databases.
Use address tiers
Keep one address for important accounts, use aliases for ongoing subscriptions, and use temporary email for quick tests. This makes unwanted mail easier to control.
Read before signing up
Look for privacy links, communication preferences and unsubscribe details. If a site hides these basics, protect your primary inbox.
Review subscriptions
Every few months, unsubscribe from messages you no longer read. A clean inbox is easier to protect and easier to search.