Getting started
Kestrel Mail uses a three-column layout: your mailboxes in the sidebar, conversations in the middle, and the selected message or thread on the right.
- Add accounts from Settings > Accounts.
- Use All Inboxes when you want one inbox across all your accounts.
- Open Compose to start a new message, then choose the sending account from the From picker when needed.
Adding an account
To add an email account:
- Open Settings (⌘,) and go to Accounts.
- Click Add account… and choose your provider: Continue with Google, Continue with Microsoft 365, Continue with iCloud Mail, or Set up with IMAP / SMTP.
- Google and Microsoft 365 sign in through your browser. iCloud asks for an app-specific password, with Apple's server settings filled in for you. For other providers, Kestrel detects server settings from your email address where it can and asks for them when it can't.
- Once signed in, your folders and messages start syncing right away.
You can add as many accounts as you need. Each one gets its own set of folders in the sidebar, and All Inboxes combines them all into one view.
Reading and organizing mail
Click a conversation to read it. If a conversation has multiple messages, they're threaded together and you can expand or collapse individual messages.
- Move to a folder — drag a conversation from the list onto any folder in the sidebar.
- Archive — press e or use the toolbar.
- Trash — press Delete or #.
- Star — press s to star or unstar. Starred messages appear in the Starred mailbox.
- Mark as junk — press ! to move a message to Junk (or back to Inbox if it's already there).
- Mark read / unread — press ⇧I to mark read or ⇧U to mark unread.
Summaries
Kestrel can summarize individual messages and entire conversation threads. Summaries appear as a short list of highlights: the key points from a single message, or one bullet per message, in order, for a thread.
Summaries run on your Mac through Apple Intelligence. Nothing is sent to a server. For better results, especially on long threads, you can download the optional enhanced model pack in Settings > AI Summaries.
Swipe actions
Swipe left or right on a conversation row to archive, trash, star, mark as read, or mark as junk. Each side has a full-swipe action and a partial-swipe action: a full swipe acts immediately, while a partial swipe shows a button first. Configure all four in Settings > Viewing.
Unsubscribe
When Kestrel detects that a message includes an unsubscribe option, it shows an Unsubscribe button in the message view — no scrolling through the email looking for a tiny link. For senders that support one-click unsubscribe, Kestrel sends the request itself; for the rest, it opens the sender's unsubscribe page or a pre-addressed email.
Rules
Rules let you automatically act on incoming messages. Set them up in Settings > Rules.
- Match messages by sender, recipient, subject, or folder.
- Actions: move to a folder, mark as read, star, or mark as spam.
- Rules run automatically when new messages arrive.
Everyday shortcuts
Kestrel uses single-key shortcuts for common actions and standard Mac shortcuts for everything else. Here's a quick reference.
Search and navigation
Search supports plain keywords as well as operators: from:, to:, cc:, bcc:, subject:, filename:, in:, before:, after:, has:attachment, and is:read / is:unread / is:starred. You can also type natural-language queries like "emails from Sarah last week" and Kestrel will figure out what you mean.
Compose
Every message you compose gets its own window, and you can keep as many open as you like while moving around the app. Switch the sending account with the From picker, reveal Cc and Bcc when you need them, and drag recipients between fields.
Attachments and message viewing
Attachments work the way you'd expect on a Mac. If an attachment has been viewed before, it's cached locally and available even when you're offline.
Use the attachment context menu to Open, Open With, Share, or save. You can also save directly to Downloads or choose a location with a save panel.
Settings and account management
Open Settings with ⌘, to manage accounts, preferences, mail rules, and advanced options. Adding new accounts and changing server settings are both in the Accounts tab.