Confirmation letter is an acknowledgment letter sent to confirm the details. These letters are formal and needs to be written in formal and professional tone.
Confirmation letter can be written for personal work like an invitation for wedding or birthday party or to respond for any letter.
It can be for official as well, like confirmation letter for business, appointment confirmation or resignation.
This letter needs to be short and concise.
Ask the reader to contact you for any query or doubt he may have.
In case of close associates and loved ones, the confirmation letters can convey warmth and happiness. However even in such a case, they should be kept short.