How to Add a Signature in Apple Mail
Step-by-step guide for Mac (2026)
Apple Mail has a love-hate relationship with HTML email signatures. Unlike Gmail or Outlook, it doesn't let you paste rich HTML directly into the signature editor without some workarounds. The app assumes you want plain text and strips out most formatting if you try the obvious approach. This is especially frustrating when you've spent time creating a beautiful signature with colors, images, and links. The good news? There are proven methods to make it work. The trick is understanding how Apple Mail processes signatures behind the scenes.
Launch Apple Mail, then click 'Mail' in the menu bar and select 'Preferences' (or 'Settings' on macOS Ventura and later). You can also use the keyboard shortcut Command+Comma to open preferences directly. The Preferences window is where all your Mail configuration happens.
Once the Preferences window opens, look for the tabs at the top and click on 'Signatures'. This is where all your email signatures live. You'll see three columns: accounts on the left, signature names in the middle, and the signature editor on the right.
Click the small '+' button at the bottom of the middle column to create a new signature. A default signature will appear with a generic name. You can create multiple signatures for different purposes, like one for work and one for personal emails.
Give your signature a descriptive name that makes sense to you. Double-click the default name and type something like 'Work - Professional' or 'Personal - Casual'. Good naming matters when you have several signatures and need to switch between them quickly.
Here's where it gets tricky with HTML signatures. Copy your signature from SigGen, then open it in a browser first. Select and copy the rendered signature from the browser, then paste it into the right panel in Apple Mail. This preserves the HTML formatting. Don't paste the raw HTML code directly.
Drag your newly created signature from the middle column to the email account in the left column. You can also use the 'Choose Signature' dropdown under each account to assign which signature gets used by default. If you have multiple accounts, repeat this for each one.
Apple Mail doesn't play nice with direct HTML pasting. If you paste raw HTML code, you'll just see the code itself in your emails. Not ideal.
The browser method works best: Copy your HTML signature code from SigGen, paste it into any text editor, save it as an .html file, then open that file in Safari or Chrome. The browser renders the signature properly. Now select everything in the browser, copy it, and paste into Apple Mail's signature editor. This preserves all the formatting.
Advanced option: You can manually edit the .mailsignature file stored in ~/Library/Mail/V10/MailData/Signatures/ (version number may vary). Quit Mail first, edit the file with your HTML, save it, then reopen Mail. This method gives you complete control but requires basic Terminal knowledge.
Signature reverts to plain text
Apple Mail sometimes strips formatting when syncing across devices via iCloud. Turn off iCloud sync for Mail temporarily, set up your signature, then re-enable it. Also check if you accidentally have 'Always match my default message font' enabled in Mail Preferences under Composing.
Images not showing
Images need to be hosted online with public URLs. Apple Mail can't embed local images in signatures reliably. Use image hosting services or upload your logo to your website first. Make sure the image URLs use HTTPS, not HTTP.
iCloud sync issues
If your signature looks perfect on your Mac but shows up broken on your iPhone, iCloud's sync is probably mangling the HTML. The safest approach is to set up signatures separately on each device rather than relying on iCloud to sync them correctly.
Signature appears twice
This happens when replying to emails if you have signature settings configured incorrectly. Go to Preferences > Signatures and check the 'Place signature above quoted text' option. Uncheck 'Always match my default message font' as well.
iOS Mail is even more restrictive than the Mac version. The built-in Settings app only lets you create plain text signatures with minimal formatting.
To get an HTML signature on iPhone or iPad, you need workarounds like emailing yourself the signature and copying it from that email into a new message, then saving it. It's clunky. Some users find it easier to just accept a simpler signature on mobile devices. Your call.