How to write a resignation letter that's effective immediately? In the first sentence, clearly state your intention to resign and that your resignation is effective immediately.I am writing to inform you that I will be resigning from my position as (Title) at (Company Name). Simply state something like "Effective this dste, consider this my two week's notice. My last day will be September 1. I am writing to inform you that I will be resigning from my position as (Title) at (Company Name). Looking to resign with a Immediate Notice Resignation Letter? Use our resignation letter template for notice-period roles. This form may be used to draft your Resignation of Resident Agent.