- Platform
- Mac
- Category
- Productivity
- Status
- Under Development
- Price
- Free
Mail Signature Manager is a native macOS app for creating, editing and organising Apple Mail signatures outside Mail’s built-in editor. It is for people who maintain multiple signatures across accounts. In development.
What it does
- Signature list and editor: a WYSIWYG editor plus an HTML editor and a live preview, so you can write the signature visually or fix the markup by hand. Images pasted into the editor are embedded and survive saving.
- Apply to Mail: the app reads Mail’s authoritative signature store (~/Library/Mail/V*/MailData/Signatures), patches only the text of rich multipart signatures so Mail keeps accepting them, and restarts Mail safely when it applies changes. It watches that folder and shows the changes Mail itself made.
- iCloud sync of your signatures through the app’s own iCloud container, with explicit Pull and Push buttons.
- Sync status view with pending changes and the last sync date.
- Runs on macOS 13 and later; the current build is compiled with the macOS 27 SDK and adopts the Liquid Glass style on macOS 26 and later.
Because Mail’s real store is protected by macOS privacy controls, the app needs Full Disk Access to write to it; without it, it degrades to reading the iCloud mirror.
Who it is for
Anyone juggling several signatures — work and personal accounts, languages, roles — who finds Mail’s preferences pane too limiting, and who wants the same set of signatures on every Mac they use.
Privacy and data
Signatures are stored where Mail stores them on your Mac and, if you use the sync, in your own iCloud container; no third-party service is involved.
Frequently asked questions
Does Mail Signature Manager change the signatures Apple Mail uses?
Yes, that is its purpose. It reads Mail’s own signature store under ~/Library/Mail and writes your edits back there — patching only the text of rich multipart signatures so Mail keeps accepting them — then restarts Mail safely so the changes are picked up. Because that folder is protected by macOS privacy controls, the app needs Full Disk Access; without it, it can only read the iCloud mirror and edits cannot reach Mail.
Can I edit signatures as HTML?
Yes. The app has a WYSIWYG editor for writing the signature visually, an HTML editor for the markup, and a live preview. Images pasted into the WYSIWYG editor are embedded in the signature so they are not lost when saving.
Does it sync signatures between Macs?
Yes, through iCloud. Signatures are stored in the app’s own iCloud container and you control the direction with explicit Pull and Push buttons; the sync status view lists pending changes and the last sync date. The app also watches Mail’s signature folder and shows changes Mail made on its own, so the two never silently diverge.
Which macOS versions does Mail Signature Manager support?
macOS 13 or later. The current build is compiled with the macOS 27 SDK, migrated to Swift 6, and on macOS 26 and later adopts the Liquid Glass interface style for its toolbar buttons; on older versions it keeps the classic look. The app is in development and not yet distributed; join the waitlist to be notified.
Get notified at launch
Mail Signature Manager is under development. Leave your email and I'll let you know the moment it ships — no spam.