Most people file the wrong one. Filing a grievance when you need an appeal can waste weeks you do not have. Here is what each one is and when to use it.
You typically have 180 days from the date of the denial to file, though some plans have windows as short as 65 days. Note the deadline the day you receive the denial letter.
A grievance does NOT reverse a denial. If your goal is to get a denied service covered or a denied claim paid, a grievance is not the right tool. Filing one creates a record, but it does not trigger the same review rights as a formal appeal.
The reviewer is an Independent Review Organization (IRO) with no financial relationship to your insurer. Their decision is binding. If they overturn your denial, your insurer must cover the service. Independent Review Organizations overturn insurer denials at meaningful rates — in some states, more than 40% of external reviews result in the denial being reversed.
For urgent medical situations, each process has an expedited version. Expedited internal appeal must be decided within 72 hours. Expedited external review can be requested simultaneously with an expedited internal appeal in life-threatening situations and must be decided within 72 hours. You qualify when the standard timeframe would seriously jeopardize your health, life, or ability to regain full function. Your doctor can certify urgency.
