Q: Is there a way to increase line spacing/leading in mail?

You can change the settings of the line spacing.

Mail menubar >>  Format  >> Show font.

Font window will be open and click on the point arrow next to the T – icon, then make a choise of none-, single- or double line spacing.

This option underlines the font, it doesn't increase the spacing between the lines.

Jowie,,talyian

Don't know if you figured this out, but in case anyone else searching has the same question—

I've had this issue as well. Just recently got a new iMac. Yosemite. There doesn't seem to be any obvious access to line-spacing, which isn't surprising—Yosemite has a lot of issues; it's like a friend who keeps trying to help you, but does it wrong.

Right, so the only solution I've found, and it works to a degree. Change the font.

Mail will render a font's leading to what it sees as normal, I'm sussing. 10/12, etc. Their default Helvetica doesn't look good.

Change your defaults—Try Damascus for composing, if you're looking for a built in one—or play around by changing the font with a test message until you find the one you like.

Apple? WT…

There is an indirect way to alter your line-height (spacing) in Apple Mail.

Write your email, or the part that you want to apply the special spacing too. Start a new TextEdit document (not plain text), and copy/paste a couple of lines of text from your Mail compose into TextEdit for boilerplate. In TextEdit, Format ▸ Text ▸ Spacing… . Try the setting in the attached screenshot, to see if it provides the expected spacing. Set the font and font-size to that in the Mail compose window. For this example, the font was 16pt Georgia.

Now, Format ▸ Font ▸ Copy Style. In the Mail Compose window, select the recipient text, and then apply Mail's Format ▸ Style ▸ Paste Style. Your spacing will change to the TextEdit setting.

Technically, one can create a custom, Favorite paragraph style in TextEdit after the font characteristic settings and spacing values are set for a segment of text. One could then right-click on selected text in Mail Compose, and from the contextual menu, choose Font ▸ Styles… . Although this approach has worked in the past on my Mavericks installation, it has now stopped working for an unknown reason, even with custom TextEdit paragraph styles that worked previously such as a red-strikethru text effect.

It's a HUGE F'UP BY APPLE.

Typical problem: you paste in some text from somewhere, and you get bizarre line spacing.

Simplest possible solution TO REMOVE A "BIZARRE" LINE SPACING:

1) highlight the text in question

2) "make plain"

3) now if desired, change back to whatever font it was.  ledding (line spacing) will now be normal and usable

If you want to "add" nonstandard line spacing.  the only solution is the complex one explained above .. paste in text from another app, which has teh line spacing you desire.

I've read all the answers to this problem, which I share with the first writer. And none of them is a practical solution. The fact remains, apple needs to include a way to change line spacing in MAIL! Currently? They do not. Period. End of sad story.

Here's a work-around I discovered. Select the offending text. Cut (Command-X) then Paste and Match Style (Command-option-shift-V). Now you can use the backspace to eliminate the double line spacing. It's fairly quick and easy. (But I agree with louisefrompittsboro, Apple needs to fix.)

I just realized that the original poster wanted to INCREASE line spacing. Sorry, this fix does the opposite. I was plagued with double spaced type that I couldn't get to single space. But I'm betting if you pasted in some double spaced type from Word, you would be stuck with that spacing, which may be what you were looking for.

Apple Feedback http://www.apple.com/feedback/