What's the difference between 'kind regards', 'regards', and 'best regards'?

The warmth scale (coldest to warmest):

"Regards" — neutral, almost cold. Used when you want to be professional but not warm. Some read it as slightly distant or even passive-aggressive when used between people who usually write more warmly.

"Best regards" — slightly warmer than "regards." Standard professional sign-off. Safe for most business emails.

"Kind regards" — warm and professional. The most common sign-off in British professional email. Slightly more personal than "best regards."

"Best" — very common, especially in American professional email. Casual but widely accepted. Some find it abrupt.

"All the best" — warm, genuinely friendly. Good for people you know.

"Yours sincerely" / "Yours faithfully" — formal letters only. "Sincerely" when you know the name; "faithfully" when you don't (UK convention).

The rule: Match the sign-off to the relationship and the email's tone. Don't sign a warm, friendly email with cold "regards." The mismatch reads as passive-aggressive.

Tags: business writing, email, professional communication, sign-offs