For a formal letter invitation, it's best to explicitly point out the purpose, event goals, and the value it can bring to participants. Polite Subject Line: Use a clear and respectful subject line, such as "Follow-Up: Request for Meeting.The deadline to request a Letter of Invitation is November 1st. Complete one form per attendee, and be sure to include all required information. Date. Name Address City, State, Zip. It provides essential details such as date, time, venue, and the purpose of the event. I am writing this letter to inform you about the upcoming__( mention the occasion or the event) It has been a while since we all have met up. An invitation letter is a written communication used to formally or informally invite someone to a specific event, occasion, or meeting. Due to the number of requests the Governor receives, he will not be able to accept every invitation. Where (What is the address of the event?