How to Filter Spam With Apple Mail

Keep Junk Mail Out of Sight and Out of Your Inbox

Spam in Mailbox
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Apple Mail's built-in junk mail filter is pretty good at determining what is and isn't junk mail. The default settings work great right out of the box, but you can also customize the settings as needed.

Turn On Junk Mail Filtering

  1. To view or edit the junk mail filter, select Preferences from the Mail menu.
  2. In the Mail Preferences window, click the Junk Mail icon.

Your first choice is whether or not to enable the junk mail filter.

We can't imagine choosing not to use the junk mail filter, but maybe there are a few lucky individuals out there who manage to fly under the radar of spammers.

There are three basic options for how Mail can handle junk mail. First, it can mark it as junk mail, but leave it in your inbox, where you check it and make the final decision.

Next, Mail can move suspected junk mail to the Junk mailbox. This is the setting we recommend for most users, however, if you're brand new to using Mail, you might choose to have it mark junk mail as such but leave it in your inbox, until you feel comfortable about its accuracy. If you choose to have junk mail sent directly to the Junk mailbox, you can still check to be sure nothing was miscategorized before you empty the mailbox and send the junk into oblivion.

Finally, you can set up additional filters to perform custom actions on junk mail (unfortunately, unleashing a plague on the sender isn't one of the options.) We'll get back to custom actions in a minute.

There are three categories of messages that can be exempt from junk mail filtering at this level: the sender is in your Address Book; the sender is in your Previous Recipients and the message was addressed using your full name. It's generally safe to check all three categories, but you can deselect any or all of them if you prefer.

There are two more options at this level. You can choose to trust your ISP's judgment about junk mail, and you can have Mail filter out junk mail before applying any rules you set up. If you're not familiar with Mail rules, check out the following two articles:

Set Up Apple Mail Rules

Take Control of Your Email in Mail

Custom Junk Mail Filtering Options

  1. To access the custom junk mail filtering options, select Preferences from the Mail menu. In the Mail Preferences window, click the Junk Mail icon. Under "When junk mail arrives," click the "Perform custom actions" radio button, and then click Advanced.
  2. Setting up custom filtering options is similar to setting up rules for other mail. You can tell Mail how it should handle mail, in this case, junk mail, that meets certain conditions.
  3. First, you can specify whether any or all of the conditions you specify must be met.
  4. The conditions you set are really a personal preference sort of thing, and there are many options to choose from, so we're not going to go through them all. If you click on each of the pop-up menus, you can decide how you want to filter your mail. You can add more conditions by clicking the plus (+) button on the right side of the window, or delete conditions by clicking the minus (-) button.
  1. Use the pop-up menus under the "Perform the following actions" section to tell Mail how it should handle messages that meet the conditions you specified.
  2. When you're satisfied with the settings, click OK. You can come back and tweak these settings at any time if you find that Mail is being either an under- or overachiever when it comes to filtering junk mail.

You can also skip the custom options sections entirely. We find the standard options do just fine, but everyone has their own preferences for how they want to handle email.

How to Mark Mail as Junk or Not Junk

  1. If you look in Mail's toolbar, you'll see a Junk icon, which sometimes changes to a Not Junk icon. If you receive a piece of email that slipped past Mail's junk filter, click once on the message to select it, then click the Junk icon to mark it as junk mail. Mail highlights junk mail in brown, so it's easy to spot.
  1. Conversely, if you look in the Junk mailbox and see that Mail tagged a legitimate email message as junk mail by mistake, click once on the message, click the Not Junk icon to re-tag it, and then move it to the mailbox of your choice.

Mail has a built-in junk filtering database that learns as you go along. It's important to identify Mail's mistakes, so it can do a better job in the future. In our experience, Mail doesn't make an awful lot of mistakes, but it does make a few now and then, enough that it's worth scanning the Junk mailbox before you empty it, to make sure you don't miss anything important. The easiest way to do this is to sort messages in the Junk mailbox by subject. So many spam messages have similar subject lines that this speeds up the process of checking them. You can also sort by sender because many spam messages have names in the From field that are obviously bogus. But there are enough legitimate-sounding names to require double-checking the subject line, which takes more time than just checking by subject in the first place.