How to Use and Rename Flags in Apple Mail on Mac (2026)

To flag a message in Apple Mail on macOS, select it, click Flag in the toolbar, then pick a color. To rename a flag, open the disclosure arrow beside Flagged in the sidebar, click the flag's name, click it again and type a new one, such as "Urgent" for Red. Flagged mail collects in the Flagged mailbox.

Flags are the closest thing Mail has to a to-do list, and it's easy to go years using only the red one. Used with a little intent, seven colors with real names turn the Flagged mailbox into a set of short lists you can open in one click. This guide covers flagging and clearing flags on macOS, renaming them, filtering by flag, flagging automatically with rules, a keyboard shortcut for each color, and what does and doesn't carry over to your iPhone.

How to flag emails in Apple Mail on Mac

In Mail on macOS, you flag a message from the Flag button in the toolbar. The flag shows in the message's header, and the message also appears in the Flagged mailbox in the sidebar. The steps below follow Apple's Mail User Guide for macOS 27:

1. Open Mail and select one or more emails.
2. Click the Flag button in the toolbar.
3. Choose a flag color from the menu.

The menu offers seven colors: Red, Orange, Yellow, Green, Blue, Purple and Gray, as Mailbutler's guide to Apple Mail flags lists them. Nothing about them is built in; Red isn't more urgent to Mail than Gray. They mean whatever you decide, which is why renaming them (below) is worth the two minutes.

There's also a keyboard route. Shift-Command-L toggles a flag on and off; users on Apple's Community forums confirm it works in Mail, and Apple lists the same keys for flagging in iCloud Mail on the web. Apple's own Mail shortcut list doesn't include it and notes that shortcuts can vary with your language and keyboard layout, so if nothing happens, check the menu bar to see what your Mac shows.

How to change a flag's color or remove it

To switch colors, select the message, click Flag again and choose the new color. To remove a flag, select one or more flagged messages, click Flag and choose Clear Flag, per Apple's guide.

I clear flags on Friday afternoons. I open Flagged, read down the list, and clear everything that's done or no longer matters. A flag that sits there for three weeks is usually a decision I've been avoiding, and the sweep is where I finally make it.

How to rename flags in Apple Mail

You rename flags from the Flagged mailbox in the Mail sidebar, and the new name then shows wherever Mail lists that flag on your Mac. Apple's Mail User Guide gives these steps:

1. In the Mail sidebar, click the disclosure arrow next to Flagged.
2. Click the name of the flag you want to rename, such as Red.
3. Click it again so the name becomes editable.
4. Type the new name and press Return.

Renamed flags travel to your other Macs when iCloud Drive is on and Mail is checked in its list of apps, according to Apple's macOS Sequoia guide. Apple doesn't say they reach your iPhone, and they don't: iDownloadBlog's flag guide notes you don't see flag names on iPhone or iPad. On the phone, a flag is just a color.

A naming scheme that survives a busy week

Name flags after what you'll do, not after a topic. "Reply" tells you the next move; "Marketing" doesn't. Here's the set I use:

Yellow and Blue stay empty on purpose. Five names is about what I can hold in my head when I'm looking at a color on my phone with no label, and the spare colors are there when a short project needs its own list. Before my last 1:1, I opened Purple and had the agenda in front of me without writing one.

How to see only one flag color in Apple Mail

To show one flag at a time, expand Flagged in the sidebar or the Favorites bar, then choose a flag; only messages with that flag appear in the message list, per Apple's guide. Click Inbox to go back to everything.

Search works too. Apple's search guide says to type "flag" in the search field and choose Message is flagged to find every flagged email. To find a single flag, type its name (your renamed one, like "Approve") and pick the suggestion under Flags. For operators, date ranges and saved searches, read the post on Apple Mail search operators and Smart Mailboxes.

How to flag emails automatically with a rule

A Mail rule can flag incoming messages that match a condition, such as a sender's address or a word in the subject. You build it in Mail > Settings > Rules. Apple's rules guide covers the steps, though it doesn't name every action:

1. In Mail, choose Mail > Settings, then click Rules.
2. Click Add Rule and give it a name.
3. Choose whether any or all conditions must be met, then set the condition, for example From contains an address.
4. Under the actions, choose Mark as Flagged, then pick the flag color. Apple Community answers describe this action and its color choice; if your version shows the color as a separate action, click the add button to add it.
5. Click OK, then choose whether the rule should also run on mail you've already received.

Rules run in the order they're listed, and Mail stops at a Stop Evaluating Rules action or once a rule moves the message to another mailbox, per Apple. If a flag rule seems to do nothing, drag it higher. To run rules on mail you already have, select the messages and choose Message > Apply Rules (Control-Command-L).

Keep flag rules narrow. I once set one to flag anything with "invoice" in the subject, and within days the Approve list was mostly receipts I never had to touch. Now that rule only matches the two addresses that send me bills to sign off. Flags you didn't choose stop meaning anything quickly.

How to add a keyboard shortcut for each flag color

Apple's Mail shortcut list has nothing for a specific flag color, but macOS lets you assign a shortcut to any menu command. Apple's Mac User Guide gives the steps:

1. Choose Apple menu > System Settings, click Keyboard, then click Keyboard Shortcuts.
2. Select App Shortcuts, click the Add (+) button, and choose Mail from the Application menu.
3. In Menu title, type the command exactly as it appears in Mail's menus, including capitals, such as Clear Flag or a flag's name.
4. Click the Keyboard shortcut field, press the keys you want, then click Done.

The menu title has to match exactly, or the shortcut won't work, and a combination that clashes with an existing shortcut is ignored. If you've renamed your flags, open the flag menu in Mail first and copy the name it shows now. For a fuller list of Mail shortcuts, see our Apple Mail keyboard shortcuts guide.

Do Apple Mail flags sync to iPhone and other Macs?

The flag itself syncs: Apple's iPhone guide says flags you add to an email appear on that email in Mail on all your Apple devices. Colors and names are less reliable. Here's what carries over:

On colors, a long-standing Apple Community answer says iCloud and Microsoft Exchange accounts support colored flags, while providers that don't fall back to red. If your work account turns every flag red on your phone, that's the provider, not a setting you missed. On the iPhone, you add a flag by opening the email, tapping the reply button and tapping Flag; tap a colored dot to choose the color, per Apple.

Why your Apple Mail flags aren't working

Most flag problems in Mail come down to the account type, a missing sync setting or a rule that never ran. Work down this list:

1. The colors don't show under Flagged. You're using only one color. Flag a message with a second color and the list appears.
2. Flags turn red on another device. The email provider doesn't store flag colors, per the Apple Community. Keep color-dependent lists on an iCloud or Exchange account, or use only Red for that account.
3. Your renamed flags are back to colors on another Mac. On both Macs, check that iCloud Drive is on and that Mail is ticked in the iCloud Drive options, per Apple.
4. Shift-Command-L does nothing. Look at the flag commands in Mail's menu bar for the shortcut your Mac shows; Apple says shortcuts vary by keyboard layout.
5. A flag rule didn't touch old mail. Rules only run on new messages unless you applied them; select the mail and choose Message > Apply Rules.
6. A custom shortcut doesn't fire. The menu title is off by a character, or the keys clash with another shortcut, per Apple.

Flags, VIPs or Follow Up Suggestions: which to use

Flags are for messages you need to act on; Mail has two other features that cover nearby jobs. Apple's macOS 27 guide describes all three:

I use VIPs for my manager and flags for the specific emails I have to act on. Making someone a VIP and also flagging all their mail doubles the noise without adding information. If you'd rather tint whole groups of senders, our guide to color coding in Mac Mail covers rules that color messages instead of flagging them.

Habits that keep the Flagged mailbox useful

• Name flags after actions. "Reply" and "Approve" beat "Clients" and "Q3".
• Use fewer colors than you have. Leave two empty for short projects.
• Clear on a schedule. A weekly sweep keeps Flagged a list of real work.
• Unflag before you archive. Once an email is done, clear the flag and file it, so Flagged only holds open work. Our guide to archiving in Mac Mail covers finding it again.
• Don't rely on names on the phone. Pick colors you can tell apart at a glance.