From Word Genius
Sometimes one little letter can completely change the meaning of a phrase. “With regard” and “with regards,” while spelled similarly, have very different meanings, and how you use them matters. Let’s take a look at the differences.
What Does Regard Mean?
Regard (without the “s”) is a homonym with a few meanings. When used as a verb with an object, it means “Consider or think of (someone or something) in a specified way.” When used as a verb without an object, it simply means to pay attention. Then it can be used as a noun to mean a particular aspect or point: “He was extremely detailed about his work in this regard.”
The plural noun regards is not always split out from regard in the dictionary, but in popular usage it usually means “best wishes.”
With Regards vs With Regard
If you’re trying to express something regarding, concerning, or on the subject of, the correct phrase would be “in/with regard to.” A less common, but still correct, usage would be “as regards,” which is probably why people start confusing when to use the “s” and when to drop it off.
Let’s look at a few examples:
“With regard to your request for time off, I have to submit it to the manager for review.”
“Please send my regards to your mother. I hope she comes home from the hospital soon.”
In the first sentence, “with regard to” means concerning. But in the second sentence, regards with an “s” is that plural noun conveying your best wishes.
“With regard” is a more formal usage that mostly pops up in business writing, so keep in mind that you probably only need to use that “s” when you’re writing a get well card.