Apple Mail (Known as Mail.app) does not support HTML signatures by default. Mail.app does however support HTML, and with a little trickery, you can have a HTML signature!

1. Create your HTML signature

Use a HTML editor or text editor, or TextEdit. Create your signature as you wish it to display. In this example we will name the file signature.html . Save or move the signature file onto the Mac you wish to use it on.

2. Check your HTML signature

Go to the file you have created and open it with Safari (web browser)

3. Save your HTML signature as a Web Archive

In Safari while you are viewing the signature, click File then Save As... Choose "Web Archive" format. When you click save, make sure you use the ".webarchive" suffix. Just save the Web Archive to the desktop for the time being.

4. Open Mail.app on your Mac and create a new signature.

In the text portion of the signature, type " TEMP SIGANTURE ". This will make the next step easier. Close the preference window and quit the Mail.app application.

5. Open Terminal (Found in Applications --> Utilities)

We need to find the signature you created in step 4. From within Terminal, type the following at the command line:

grep -i "TEMP SIGNATURE" ~/Library/Mail/Signatures/*

You should get a result with a strange file name which looks something like the following:

84FC-FD6F765AB3EE4.webarchive

Now we replace the file we have found with our own signature.webarchive as follows (Remember to use the strange file name you found instead of my example):

cp ~/Desktop/signature.webarchive ~/Library/Mail/Signatures/84FC-FD6F765AB3EE4.webarchive

6. Check your handywork!

Run Mail.app and create a new email. Select your new signature using the signature drop down box. Your signature should look the same as it did when you opened it in Safari.

Cheers,

Darren!