Checking my last day of health coverage - what worked for you?

I am not sure what date my benefits stop after being let go as a data-entry clerk. I have read a lot of threads here and could not find my exact situation. I do not want to be surprised by a bill. What should I do about appointments?

Ask HR to confirm the exact date in writing. I also called the insurance company to double-check.

Dental and vision sometimes end on a different date from medical. Mine did.