Approval letters are document that are sent confirming or approving any fact or action for which consent is required to perform or implement. Thus, these kinds of letters have to be drafted with authenticity and clarity so that no alterity or mis-understanding is caused due to it. In order to impart a communicative yet professional look to the letter one must ensure to maintain the following points, irrespective of the kind of approval.
Begin the letter with a line of confirmation and also explicate the reason of approval if it is relevant to the context.
The letter should also bear the details of the proceeding and further action that is needed to be taken by the recipient.
If the approval is subjected for a timeline, then the letter should also have a clear mention about it. This would help to denote the commencement of approval or a period within which the approval would remain valid.
Depending on the content and type of approval one can close the letter in congratulatory tone.
Ensure to use simple and lucid language i.e easily understandable without being much verbose.
As these are important piece of document, proofread the approval letter prior sending in order to avoid heedless errors.