Getting pre-authorization (also called prior authorization) starts with your doctor’s office submitting a request to your insurance company, but there are things you can do at every stage to speed the process along and avoid a denial. The whole process typically takes anywhere from 24 hours to 7 calendar days, depending on urgency and your plan type.
What Prior Authorization Actually Is
Prior authorization is your insurance company’s way of confirming that a treatment, procedure, or medication is medically necessary before they agree to cover it. Your insurer reviews the request against clinical guidelines, peer-reviewed evidence, and their own coverage criteria. If the request checks those boxes, they approve it. If not, they deny it, and you or your doctor can appeal.
Not every medical service requires prior authorization. The ones that typically do fall into a few broad categories: specialty medications (especially biologics and high-cost drugs), advanced imaging like MRIs and CT scans, elective surgeries, durable medical equipment such as power wheelchairs and prosthetics, and out-of-network care. Your insurance plan’s website or member services line will have a specific list of what requires pre-approval under your policy.
The Step-by-Step Process
Your doctor’s office handles most of the heavy lifting, but understanding each step helps you follow up effectively and catch problems early.
1. Confirm Your Coverage and Eligibility
Before anything else, verify that the service you need is covered under your plan and that your policy is active. You can do this by calling the number on the back of your insurance card or logging into your insurer’s member portal. This step catches the simplest and most frustrating reason for denial: 17% of denied requests are for services the plan simply doesn’t cover. Finding this out before your doctor submits paperwork saves everyone time.
2. Check Whether the Service Needs Authorization
Your doctor’s billing staff will typically know this, but you can double-check by looking at your plan’s provider manual or calling member services. Ask specifically whether the procedure code or medication requires prior authorization. Some plans require it for brand-name drugs but not generics, or for outpatient surgery but not office visits.
3. Your Doctor Submits the Request
Your doctor’s office gathers the clinical documentation and submits it to your insurer. This usually includes your diagnosis, the specific treatment being requested, your medical history, and any evidence showing why this particular service is needed. Submissions go through an electronic portal or by fax. Once submitted, you should receive a reference number. Keep it.
4. The Insurer Reviews and Decides
The insurance company’s medical reviewers evaluate the request. They’re looking at whether the treatment aligns with established clinical guidelines and whether less expensive alternatives have already been tried. For standard requests, insurers must respond within 7 calendar days. Expedited requests, used when a delay could seriously harm your health, require a response within 72 hours. For prescription drugs, the timeline is even tighter: 24 hours in many cases.
5. You Get a Decision
The insurer notifies both you and your doctor. If approved, you’ll receive an authorization number and can schedule the service. If denied, the notice must include a specific reason for the denial.
What Insurers Look For
Insurance reviewers evaluate your request based on scientific evidence, established clinical practice guidelines, and safety data. In practical terms, they want to see that the treatment is appropriate for your specific diagnosis, that you’ve tried standard first-line treatments when applicable (this is called step therapy), and that the requested service isn’t experimental or cosmetic under your plan’s definitions.
If your doctor is prescribing a medication for a use that’s different from its original FDA approval (off-label use), the request can still be approved if there’s supporting evidence from recognized drug databases or peer-reviewed medical literature. This is where your doctor’s documentation matters most. Submitting observational studies, treatment guidelines, or consensus statements alongside the request can make the difference between approval and denial, especially for less common conditions.
How to Improve Your Chances of Approval
The single biggest thing you can do is make sure your doctor’s office submits thorough documentation the first time. Nearly a quarter of denials happen simply because the insurer didn’t receive enough information to make a decision. Call your doctor’s office a day or two after submission to confirm everything went through. Then call your insurance company to confirm they received it and ask if any additional documentation is needed.
Keep a written log of every call you make: the date, the representative’s name, and what they told you. If your authorization is for a time-sensitive procedure, ask your doctor’s office to submit it as an expedited request, which forces a decision within 72 hours. You’re allowed to request this whenever a standard timeline could negatively affect your health.
What to Do If You’re Denied
A denial isn’t the end of the road. The most common reasons for denial are that the insurer considers the service not medically appropriate (47% of denials), that they lack sufficient information (23%), or that the service isn’t covered under your plan (17%). Your response depends on which reason applies.
If the denial is for insufficient information, have your doctor resubmit with more detailed clinical notes. This is often the easiest fix. If the insurer questions medical necessity, your doctor can request a peer-to-peer review, which is a phone call between your treating physician and a doctor employed by the insurance company. This direct conversation often resolves disagreements faster than paperwork alone.
If those steps don’t work, you can file a formal appeal. Most plans give you up to 180 days from the denial date to appeal. The process typically has three levels: two internal appeals reviewed by the insurance company, and one external appeal reviewed by an independent third party. Before you start, confirm that the service isn’t specifically excluded from your plan. Appealing an excluded service won’t change the outcome regardless of medical evidence.
For the internal appeal, write a letter (or have your doctor write one) explaining why the treatment is necessary, and attach supporting medical records, lab results, or relevant clinical guidelines. If the first internal appeal is denied, escalate to the second. If both internal appeals fail, you have the right to an external review, where an independent reviewer outside the insurance company makes the final call. If your situation is urgent, you can request an expedited appeal, which requires the insurer to decide within 72 hours.
How Long an Approval Lasts
Once you have an approved authorization, it doesn’t last forever. The validity period varies by insurer and type of service, but most approvals are tied to a specific timeframe or course of treatment. For chronic conditions, many insurers now make authorizations valid for the full length of treatment. If your dose changes, the authorization should remain valid for at least one year without needing resubmission.
If you switch insurance plans, your new plan is generally expected to honor an existing prior authorization for a minimum of 90 days. This grace period is meant to prevent gaps in treatment while your new insurer processes its own review. If you’re on a stable treatment regimen and your plan changes at open enrollment, contact your new insurer before the switch to understand their prior authorization requirements.
New Rules Taking Effect in 2026 and 2027
Federal regulations finalized in 2024 are rolling out changes that should make prior authorization less painful. Starting in January 2026, Medicare Advantage plans, Medicaid, and marketplace insurers must respond to standard requests within 7 calendar days and provide a specific reason for any denial. They’ll also be required to publicly report their approval and denial rates.
By October 2027, additional rules will push insurers toward fully electronic prior authorization systems, which should reduce the fax-and-phone-tag cycle that currently bogs down the process. These changes won’t eliminate prior authorization, but they set enforceable deadlines and transparency requirements that didn’t exist before.