Acceptance letter for an invitation to an event is an expression of your willingness and availability to attend the event. Its purpose is to acknowledge the receipt of the invitation letter and to let the host know that you can participate on the event.
In accepting invitation for any event, it is important to make a timely and brief response. You have to consider the three important parts of the body of the letter which should not be eliminated in writing.
The first part should state an expression of your appreciation to receive an invite. Use positive tones to show your pleasure and honor upon receiving the invitation. The second part of the letter should express the brief details of the event.
This is your way of reiterating the important details such as the place and date of the occasion. Finally, you have to confirm your coming and say a little expectation about the event.
When the invitation is personal in nature, the formality required by letters may be dispensed with. However, if the invitation for an event is formal, there must be strict adherence to the body of a letter.