State rules on auto insurance nonrenewal notice When the mail arrives carrying a letter from a car insurance provider, the natural inclination is often to toss it into the "later" pile. However, if that envelope contains a notice of nonrenewal, ignoring it can lead to a costly, stress-filled scramble. Nonrenewal is the decision by a car insurance company to end a policy at the expiration date, and it’s a critical time bomb with a fuse length determined entirely by state law.