[Your letterhead, if desired; if not, your return address]
[Date of letter-month, day, and year]
[Recipient's first and last names]
[Company name]
[Street or P.O. box address]
[City, State ZIP code]
Dear [recipient's name]:
A little bird told me that you have a big birthday coming up, so I want to send you huge congratulations! The little bird also told me that you will be over the hill as you turn 40, but I just want to say "hogwash" to that! You will always be young at heart in my book, and you’ve always looked way younger than you are anyway.
I would love to get together so we can celebrate your birthday in person, so please give me a call sometime soon and we can make plans. It will be so much fun to give you a big birthday hug and enjoy some birthday cake together. Best wishes for many more happy and healthy decades, and again, congratulations on celebrating this exciting milestone!
Sincerely,
[Signature]
[Sender's first and last names]