A resignation implies future activity. Friends, colleagues, and students will want to know what is next for me.Both possibilities involve leaving your job; however, there are some benefits you're entitled to get when you retire instead of resigning. A resignation letter should be written at least 30 days prior to the effective date of resignation. A resignation letter will work, but should I send a retire notice? Depends on your company's policies. The resignation letter must identify your last day of employment. A letter of resignation usually contains a reason and gives a date upon which the resignation is effective. The term "voluntary separation" as used in the statute means leaving employment of one's own free will.