Apple Mail plugins and extensions that still work

The Apple Mail plugins and extensions that work on macOS 27 today are SpamSieve for spam, Mailbutler for tracking, templates and AI, MailTrackerBlocker for spy pixels, GPG Mail for encryption (in beta), Grammarly for your writing, and Apple's own ChatGPT extension for drafting. If what you want is more than an add-on can give, such as junk stopped at the sender, search that finds what you remember, or Claude working in your mail, Alrighty is a separate Mac mail app that does that. It is not a plugin. It replaces Apple Mail.

Many lists for this search were written for the old plugins, which Apple Mail stopped loading with macOS Sonoma. And none of them says where each tool sends your mail. This page lists only what you can install and use today, and for each one it says what leaves your Mac.

How we checked

We read each tool's own page, store listing or help page on November 4, 2026, and every fact links to its source. For each tool we noted what it adds to Mail, what it costs, which macOS it supports, and where it sends your mail. Alrighty is our app, and it's listed first.

Why old Apple Mail plugins stopped working

Apple Mail used to load plugins: code from other developers that ran inside Mail itself. Apple replaced them with Mail extensions, which can do four kinds of job and no more. SmallCubed, which made MailTags and Mail Act-On, puts it plainly on its support page: "Mail on macOS 14 (Sonoma) will no longer load Mail Plugins."

Today, apps from the App Store can add four kinds of Mail extension, per Apple:

• Compose extensions help you write, for example by checking addresses as you type them.
• Action extensions help manage your inbox, for example by moving messages to Junk or Archive.
• Content blocker extensions stop remote content, such as tracking images, from loading.
• Security extensions encrypt, decrypt and sign messages.

Some tools on this page aren't Mail extensions at all. SpamSieve is its own app that works with Mail. Grammarly is a desktop app that works in most apps on your Mac. ChatGPT comes through Apple Intelligence. They still add to Apple Mail, so they're here.

How do I turn on a Mail extension?

Installing an extension doesn't turn it on. Apple says "you must turn it on in Extensions settings in Mail before you can use it" (Apple).

1. In Mail, choose Mail > Settings.
2. Click Extensions.
3. Select the checkbox next to the extension.

To remove one, select it and click Uninstall, or delete the app that contains it. These steps match Apple's Mail guide for macOS 27 as of November 2026.

Apple Mail add-ons at a glance

Tool	What it adds	Price	Works on macOS 27	What leaves your Mac
Alrighty	Its own mail app: Stop mail, Clean up, search, your AI	14-day trial, then Free or Pro	Yes, Apple silicon only	Emails its AI and Clean up read, to its server and AI models
SpamSieve	Spam filter that learns from your mail	$39.99 once	Yes	Nothing, it filters on your Mac
Mailbutler	Tracking, templates, notes, AI writing	From $5 a month	Yes	Account data to its servers; email body to OpenAI for AI
MailTrackerBlocker	Blocks spy pixels	$6.99 once	Yes	Not stated on its listing
GPG Mail	PGP encryption and signing	Support plan; 30-day trial	In beta	Your public key, only if you upload it
Grammarly	Spelling, grammar and tone as you type	Free; Pro is paid	Yes	What you write, to Grammarly
ChatGPT extension	Compose with ChatGPT in Writing Tools	Free, account optional	Yes, where available	Only the request you send to ChatGPT

Alrighty: best if you'd rather replace Apple Mail than patch it

Alrighty isn't a plugin, and it doesn't run inside Apple Mail. It's a separate desktop mail app, for Mac, Windows and Linux, that takes your iCloud, Gmail and Outlook accounts into one inbox. It belongs on this page because most people search for plugins to fix three things in Apple Mail: junk, search and AI. Alrighty builds those in.

• Stop mail. One click ends a sender's mail. Alrighty unsubscribes in every way the message offers, archives their mail, and moves their new mail out as it arrives. A spam filter like SpamSieve moves spam aside. Stop mail ends the newsletters and lists you never wanted, too.
• Clean up. It lists the senders you probably don't want, such as scams, cold outreach and newsletters you never open, so you can stop them all at once. A sure phishing message goes to Junk, and a likely one stays with a warning.
• Search that finds what you remember. Search runs on your Mac and matches what you mean as well as the words, so "when is my flight" finds the airline's confirmation. It keeps its own index and doesn't rely on Spotlight, which Apple Mail search does. Our Apple Mail search guide has the fixes if you'd rather stay.
• Your own AI in your mail. Claude, ChatGPT's desktop app, Codex, Cursor or a local model can read and search your mail through Alrighty. It can also work in a window you watch: open mail, write replies, file messages. Nothing sends until you click Send.
• Suggested replies. Signed in, opening a reply starts a draft in your voice, written from what you sent that person before. It's always a draft, and you send it.

Where your mail goes. Your mail stays with Apple, Google and Microsoft, and Alrighty keeps its copy and its search index on your Mac. Your passwords and sign-ins stay on your Mac, encrypted with a key from your system's keychain. Its AI features and Clean up send only the emails they need to Alrighty's server, which passes them to an AI model (OpenAI's for answers and replies). Signed out, nothing goes to Alrighty's server.

Price. A 14-day trial with no card, then a Free plan or Pro. See everything Alrighty does.

What it can't do. It's not an add-on, so you leave Apple Mail to use it. On a Mac, it needs Apple silicon. It takes iCloud, Gmail and Outlook accounts only, so no Yahoo, AOL, Fastmail or other IMAP providers. There's no iPhone app and no calendar, and it has no PGP encryption. It's a new app with no long track record.

Pick it if you were about to install three plugins to fix junk, search and AI, and would rather have one app that does all three. Our Apple Mail alternatives page compares it with the other apps that replace Mail.

SpamSieve: best spam filter for Apple Mail

SpamSieve is a spam filter that learns from your own mail. It works with "Apple Mail (Mail.app), Outlook, Airmail, MailMate, GyazMail, and more," with IMAP, Exchange and POP accounts (C-Command). It keeps an allowlist of people you've written to, so their mail is never marked as spam.

Works on macOS 27. Yes. Its page lists "macOS 10.13 High Sierra through macOS 27 Golden Gate." Version 3.3.2 came out on September 18, 2026.

What leaves your Mac. Nothing. SpamSieve "does not need access to your mail account login and does not transmit your mail data anywhere. All the processing is done on your Mac."

Price. $39.99 once, or $63.98 for a family or two users (store). It's a one-time purchase, and minor updates are free. There's a free trial.

What it can't do. It filters spam. It doesn't unsubscribe you from lists, and it doesn't list cold senders for you to review. Mail you signed up for and no longer want isn't spam to it. Our spam blocker guide compares it with the other filters.

Pick it if you want to keep Apple Mail and want a stronger spam filter that runs on your Mac.

Mailbutler: best for tracking, templates and AI in Apple Mail

Mailbutler is an extension for Apple Mail, Gmail and Outlook. It adds email tracking, templates, mail merge, notes, tasks and signatures, and a Smart Assistant that writes and improves emails with AI on its Smart plan (pricing).

Works on macOS 27. Yes. Its compatibility page lists Golden Gate (27) back to Ventura (13), with iCloud, Gmail, IMAP, Yahoo and Exchange 2013 or later. You install it from the Mac App Store and create a Mailbutler account.

What leaves your Mac. Mailbutler says "Our servers are located in Frankfurt, Germany, and we don’t save or process any of the content of your emails," and "We only transmit your email body to OpenAI when you use the Smart Assistant feature" (Mailbutler). Its tracking tells you when your recipients open your mail and click your links.

Price. A free 14-day trial with no credit card. Then Starter is $5 a month, Professional $9 and Smart $14, per user, with about 25% off for yearly billing (pricing). The Mac App Store lists the same plans as in-app purchases.

What it can't do. It's a subscription, and the AI is only on the Smart plan and up. It adds tools for sending mail, not for stopping the mail you get.

Pick it if you send a lot of mail from Apple Mail and want to know who opened it, with templates and AI drafts.

MailTrackerBlocker: best for blocking spy pixels

MailTrackerBlocker is a Mail extension that "Blocks most spy pixels which can capture your IP address and function as read receipts and more," and shows what it blocked in the message header. It "Identifies over 300 of the most common email marketing vendors" (Mac App Store).

Works on macOS 27. Yes. It needs macOS 14.3 or later, and version 1.3.0 came out on October 27, 2026.

Price. $6.99 once.

What to know. Apple Mail already has Protect Mail Activity, which hides your IP address and downloads remote content privately (Apple). MailTrackerBlocker adds a list of who tracked you. And the listing warns that "Mail only allows up to one active Message Security Extension at a time," so setting it as yours "will not allow your GPG extension to fully function." Its listing doesn't say whether it sends anything off your Mac.

Pick it if you want to see which senders track you, not only block them.

GPG Mail: best for PGP encryption, while it's in beta

GPG Mail is the Mail extension in GPG Suite. It encrypts, decrypts, signs and verifies mail with OpenPGP keys, which you manage in GPG Keychain (GPGTools).

Works on macOS 27. Only in beta. GPGTools says "GPG Mail 8 is currently in beta" for macOS Golden Gate, and that "Some features we consider essential are still missing." It can't say when the beta ends, because Apple hasn't shared a timeline.

Price. "GPG Mail 8 beta requires an active GPG Mail 7 Support Plan," and the plan "will be a yearly subscription starting with GPG Mail 8." You can use GPG Mail 8 free for 30 days if you haven't had a trial before. The page we read doesn't show the plan's price.

What leaves your Mac. When you create a key, you can choose to upload it to a key server so others can find it. That upload is optional.

Pick it if you exchange PGP-encrypted mail and can live with a beta. If you only need encryption sometimes, Mail can also sign and encrypt with personal certificates (S/MIME), per Apple.

Grammarly: best for checking what you write

Grammarly isn't a Mail extension. It's a desktop app, and Grammarly says it "will work in Apple Mail, Outlook, Gmail, and most other email clients" (Grammarly). It checks spelling, grammar and tone as you type, in Mail and in other apps.

Works on macOS 27. It needs "macOS 10.15 or newer."

Price. You can use the free version "as long as you want." Grammarly Pro adds more suggestions. We didn't check Pro's price.

What leaves your Mac. What you write is checked by Grammarly. It says it does "not and will not sell the content you upload," and that you can stop it from training on your writing: "turn off Product Improvement and Training in your account settings" (Grammarly).

Pick it if you want the same writing help in Mail, Slack and your browser.

ChatGPT in Writing Tools: best built-in AI for drafts

Apple Mail has no ChatGPT plugin, but macOS does. With Apple Intelligence on, Writing Tools can use the ChatGPT extension. In a message, Control-click the text, choose Show Writing Tools, click Compose, and describe what you want ChatGPT to write (Apple).

Turn it on. In System Settings, open Apple Intelligence & Siri, click ChatGPT, then Set Up. You don't need a ChatGPT account (Apple).

What leaves your Mac. Only the request you choose to send. Apple says "You control when ChatGPT is used and are asked before any of your information is shared," and your IP address is hidden from ChatGPT. Signed in, your ChatGPT account settings and OpenAI's policies apply.

What it can't do. It writes from what you give it. It can't search your mailbox or read your past mail. And "Apple Intelligence on macOS 27 is not available in all languages or regions," and the extension works only where ChatGPT is available.

Pick it if you want ChatGPT to draft an email without leaving Mail and without installing anything.

Can I add Claude or ChatGPT to Apple Mail?

Not as a plugin. ChatGPT can draft in Mail through Writing Tools, as above, but it can't read your mailbox. For an AI that reads and searches your mail, you connect it with an MCP server. For Apple Mail, those servers mostly drive Mail with AppleScript, and our Apple Mail MCP server guide compares them, including which ones can send without asking you.

Alrighty takes a different route. It's the mail app, and Claude or ChatGPT's desktop app connects to it with Connect AI. The AI can read, search and draft, and nothing sends until you click Send. Our guide to letting Claude read your email has the steps.

What happened to MailTags and Mail Act-On?

They're no longer sold. SmallCubed says "We have stopped selling MailSuite to new customers as it will not work in Sonoma" (SmallCubed). MailSuite was the bundle of MailTags, Mail Act-On and SigPro. SmallCubed now makes MailMaven, a separate mail app, so like Alrighty it replaces Apple Mail rather than adding to it.

How to choose

• Junk, search and AI fixed in one app, and you'll leave Apple Mail: Alrighty.
• A stronger spam filter that runs on your Mac: SpamSieve.
• Open tracking, templates and AI drafts for mail you send: Mailbutler.
• A list of who tracks you: MailTrackerBlocker.
• PGP encryption: GPG Mail, in beta on macOS 27.
• Writing help in every app: Grammarly.
• A quick AI draft with nothing to install: ChatGPT in Writing Tools.
• Claude reading your Apple Mail: an MCP server, from our Apple Mail MCP server guide.

Questions

Does Apple Mail still support plugins?

No. Mail stopped loading plugins in macOS 14 Sonoma. It now takes Mail extensions from the App Store, which you turn on in Mail > Settings > Extensions. Some tools, such as SpamSieve and Grammarly, work with Mail from their own apps instead.

Why doesn't my Mail extension show up?

Installing an extension doesn't turn it on. Open Mail > Settings > Extensions and select its checkbox. If its button isn't in the toolbar, customize the toolbar to add it.

Can I use GPG Mail and MailTrackerBlocker together?

Not fully. Mail allows only one active message security extension at a time. If you set MailTrackerBlocker as that extension to get its tracker report, GPG Mail won't fully work.

Is there a ChatGPT plugin for Apple Mail?

There's no plugin, but the ChatGPT extension in Apple's Writing Tools drafts text in Mail. It works only where Apple Intelligence and ChatGPT are available, and it can't read your mailbox.

Do Apple Mail extensions read my email?

It depends on the tool. SpamSieve says it processes everything on your Mac and sends nothing. Mailbutler sends your email body to OpenAI when you use its Smart Assistant. Check each tool's own page before you turn it on.