In the main section of your letter, mention your intended last working day. State your resignation.I'd like to leave threes weeks before I had originally intended to leave. I still have a whole three months before the last day listed in my resignation. You are contractually obligated to 2 months. So I would put that date in my resignation letter. If you put in a signed written notice that you are resigning from a company with a date in it as to when your last day. I am writing to inform you that I will be resigning from my position as (Title) at (Company Name). I currently work at an at-will employment job in Michigan. Last day worked,; reason for termination; letter of resignation.