Where apps hide your files

Outlook for Mac signature files

Updated 2026-10-28 · 5 min read

Legacy Outlook for Mac stores each signature as a small file inside its hidden profile folder. Here is the path, why web guides disagree, and the safest way to carry signatures to another Mac.

The location

In the legacy Outlook for Mac profile, signatures are here:

~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/Main Profile/Data/Signatures

On the Mac used for this guide that folder holds a numbered subfolder, and inside it one file per signature with a generated name ending in .olk15Signature. Only the names were listed; no signature was opened. A university IT guide for restoring signatures on a Mac gives the same Data/Signatures path. Microsoft's own pages do not say where signatures are stored.

The folder sits inside ~/Library/Group Containers, which Finder hides. Press ⇧⌘G, paste the path and press Return, or run:

open ~/Library/Group\ Containers/UBF8T346G9.Office/Outlook/Outlook\ 15\ Profiles/Main\ Profile/Data/Signatures

Which Outlook are you on

Web pages disagree about where Outlook for Mac keeps signatures, because the app changed. Third-party guides list at least four locations:

• .../Outlook/Outlook 15 Profiles/Main Profile/Data/Signatures (verified above, legacy Outlook)
• .../UBF8T346G9.Office/Outlook/Signatures
• .../UBF8T346G9.Office/User Content.localized/Signatures
• ~/Library/Containers/com.microsoft.Outlook/Data/Library/Application Support/Outlook/Signatures

Only the first could be confirmed. On the Mac used for this guide, the container path above does not exist (its Application Support holds com.microsoft.Outlook and Microsoft, but no Signatures folder), UBF8T346G9.Office/Outlook holds only Outlook 15 Profiles and Outlook Sound Sets, and User Content.localized holds templates, not signatures. If your Outlook is a newer build and the first path is empty, search the other three, or use the search tip at the end of this post.

Microsoft does not document the new Outlook's storage, so the safest way to see your signatures on any version is inside the app.

See and edit them in Outlook

Microsoft's current article gives different menus for the two interfaces.

• New Outlook for Mac: open the Outlook menu, choose Settings, then Mail, then Signatures. Select a signature under Signature name and click Edit.
• Legacy Outlook for Mac: open the Outlook menu, choose Settings, then Email, then Signatures. The + button adds a signature, and double-clicking Untitled names a new one.

Defaults are set on the same screen: under Set default signature (new Outlook) or Choose default signature (legacy), pick an account, then choose the signature for new messages and for replies or forwards. Each account needs its own default.

Copy a signature out without touching the folder

The reliable way to move a signature is through the editor, because it works on every version and does not depend on a file format Microsoft has not published:

1. Open the signature in the editor as above.
2. Press ⌘A to select everything, then ⌘C to copy.
3. Paste it into a TextEdit document in rich text mode, or straight into the signature editor on the other Mac, with ⌘V.

Pictures and links may come across with the paste, but Microsoft does not say so. Check the result by sending yourself a test message before you rely on it, since formatting can shift between versions.

Back up the signature files

If you do want the files, quit Outlook first, then copy the whole Signatures folder to your Desktop with Finder: hold ⌥ while you drag, or use Edit > Copy and Edit > Paste Item. Copying changes nothing in the original. Keep the copy; do not move the original folder out of the profile.

Microsoft does not describe restoring by file copy. A university guide restores signatures by closing Outlook and pasting the backed-up files into the same Data/Signatures folder, which is the nearest thing to a documented method, but test on one signature first and keep the copy if Outlook does not list it afterwards.

Do signatures roam between Macs

Do not rely on it. Microsoft's roaming signatures page describes Outlook for Windows (build 2303 or later) with Microsoft 365 or Outlook.com mailboxes, and says nothing about the Mac. Third-party reports (Office Watch, Exclaimer) say signatures do not roam in Outlook for Mac, including the new one, so a Mac keeps its own. Microsoft's Mac signature article does not mention syncing. If you use Outlook on two Macs, make each signature once per Mac, or paste it as shown above.

Signature images and files

If a signature shows a logo, the picture is either embedded in the signature or loaded from a web address. Embedded pictures may travel with a copy-and-paste; check after pasting. A logo loaded from a web address needs that address to stay online. Keep the original logo file somewhere you can find it.

Why a normal search misses it

Signature files carry generated names and live in a protected hidden folder, so Spotlight and Finder searches for your company name or the text of a signature find nothing.

Finding them again

Typing olk15Signature into Everywhere lists every signature file in the profile, wherever it sits, and ⌘↵ shows one in Finder. This works once Everywhere has Full Disk Access, because Group Containers is a protected area. It matches file names only, so it cannot search for the words inside a signature, and if the extension does not appear on your version, type Signatures and read the folder column instead.

Common questions

Where are Outlook signatures stored on a Mac?

In legacy Outlook for Mac, at ~/Library/Group Containers/UBF8T346G9.Office/Outlook/Outlook 15 Profiles/Main Profile/Data/Signatures, as files ending in .olk15Signature. Microsoft does not document the location for the new Outlook.

How do I move my Outlook signature to a new Mac?

Open the signature in Outlook's signature editor, select all, copy it, and paste it into the editor on the new Mac. Copying the files is a fallback that Microsoft does not describe.

Do Outlook for Mac signatures sync between computers?

Do not count on it. Microsoft's roaming signatures page covers only Outlook for Windows, and third-party reports say signatures do not roam in Outlook for Mac, including the new Outlook. Plan to set them up on each Mac.

How do I open the signature settings in Outlook for Mac?

In the new Outlook, choose Outlook > Settings > Mail > Signatures. In legacy Outlook, choose Outlook > Settings > Email > Signatures.