Precertification is a requirement from your health insurance company to approve a medical service before you receive it. If your plan requires precertification for a specific procedure, test, or medication, your provider needs to get a green light from the insurer confirming the service is medically necessary. Without that approval, your insurer can reduce your payment or deny coverage entirely, leaving you responsible for the bill.
You’ll also see this called “prior authorization” or “preauthorization.” These terms are interchangeable in practice. A related but slightly different concept, predetermination, estimates what your plan will pay before treatment, but precertification is the actual approval gate that determines whether coverage applies at all.
How Precertification Works
The process typically starts when your doctor recommends a procedure, imaging study, or medication that your insurance plan flags as requiring approval. Your provider’s office submits a request to the insurer with clinical documentation explaining why the service is medically necessary for your specific situation. The insurer reviews that information, sometimes requesting additional records, and then issues a decision: approved, denied, or approved with modifications.
You don’t usually need to file this yourself. The provider’s billing or administrative staff handles the submission. But the outcome directly affects you, so it’s worth confirming that precertification has been obtained before your scheduled procedure. If your provider’s office assumes it’s been handled and it hasn’t, you’re the one who may face a surprise bill.
Which Services Typically Need It
Managed care plans like HMOs and PPOs are the most likely to require precertification, and the list of covered services varies by insurer and even by individual plan. That said, certain categories come up consistently:
- Advanced imaging: CT scans, MRIs, and PET scans
- Inpatient hospital stays and observation services
- Outpatient surgical procedures, especially elective or cosmetic-adjacent ones
- Invasive procedures like colonoscopies
- Specialty medications, particularly newer or high-cost drugs
Medicare has its own specific list for hospital outpatient services. As of 2023, procedures requiring prior authorization under Medicare include eyelid surgery (blepharoplasty), Botox injections, rhinoplasty, vein ablation, panniculectomy, spinal neurostimulator implants, cervical fusion with disc removal, and facet joint interventions. Private insurers maintain their own lists, which tend to be longer.
How Long Approval Takes
There’s no single national standard for how quickly insurers must respond to a precertification request, though that’s changing. The AMA has pushed for laws requiring insurers to respond within 48 hours for non-urgent requests and 24 hours for urgent ones. Some states already enforce tighter timelines. Washington, D.C., New Jersey, and Vermont all require a 24-hour turnaround for urgent requests.
At the federal level, CMS issued a final rule in January 2024 that will require payers to respond within 72 hours for urgent requests and within one week for non-urgent requests. These requirements take effect in 2026, with electronic system upgrades required by 2027. Until then, response times vary widely depending on your insurer. In practice, straightforward requests often come back within a few business days, while complex cases involving appeals or additional documentation can stretch into weeks.
Approvals Can Expire
A precertification approval isn’t permanent. Each approval comes with a validity window, and if your procedure or treatment extends beyond that window, you’ll need a new one. This catches people off guard most often with ongoing medications. One patient profiled by KFF Health News had been on a weight-loss medication for seven months before discovering that her prior authorization had quietly expired, disrupting her treatment.
The tricky part is that expiration timelines differ between insurance companies, between plans within the same company, and even between different services on the same plan. Your insurer can also change its drug formulary at any time and require a fresh authorization for a medication you’ve been taking for months. The most reliable way to check how long your approval lasts is to call your insurance company’s customer service line directly. Don’t assume your provider’s office is tracking this for you.
What Happens Without Precertification
If a service that requires precertification is performed without it, your insurer can reduce the payment or deny the claim outright. That gap falls to you or your provider, depending on the circumstances. In many cases, the patient ends up absorbing the cost. Even when a retroactive authorization is possible, it adds delays and paperwork with no guarantee of success.
The financial burden extends beyond individual bills. The administrative cost of managing precertification is significant for medical practices, often requiring staff to spend hours on phone calls and documentation for a single approval. This friction is one reason a growing number of physician practices are shifting to cash-only models, bypassing insurance entirely. For patients, the consequences can go beyond money. When prior authorizations are delayed or denied, some people postpone or skip treatment altogether, and insurers sometimes require patients to try cheaper alternatives before approving the originally prescribed treatment, a practice called step therapy that can add weeks or months before you receive the care your doctor recommended.
How to Protect Yourself
Before any scheduled procedure, imaging study, or new medication, ask your provider’s office directly: “Has precertification been obtained?” Get the authorization number if one has been issued. If your plan is an HMO or PPO and you’re seeing an out-of-network provider, be especially cautious. Managed care plans can deny or sharply reduce benefits for care obtained outside their network or without proper authorization.
For ongoing treatments, keep a record of when your authorization was granted and ask your insurer how long it’s valid. Set a reminder to check in before it expires. If your authorization is denied, you have the right to appeal. Your provider’s office can submit additional clinical documentation, and most insurers have both an internal appeal process and an external review option through your state’s insurance department.
Starting in 2026, federal rules will require insurers to be more transparent about prior authorization decisions and faster in their responses. Until then, staying proactive is the most reliable way to avoid coverage gaps that cost you money or delay your care.