Prior authorization, or preauthorization, is a utilization management process used by some health insurance companies in the United States to determine if they will cover a prescribed procedure, service, or medication.

Prior authorisation is a check run by some insurance companies or third-party payers in the United States before they will agree to cover certain prescribed medications or medical procedures. According to insurance companies the reasons they require prior authorizations include age, medical necessity, checking for the availability of a cheaper generic alternative, or checking for drug interactions. There is controversy surrounding prior authorisations and public opinion does vary about why insurance providers require it. The primary controversial reason is that it benefits some insurance companies as they allegedly avoid paying for expensive patient treatments and increase business profits at the expense of patient health. A failed authorisation may result in a requested service being denied or an insurance company requiring the patient to go through a separate process known as "Step therapy". Step therapy dictates that a patient must first see unsuccessful results from a medication or service preferred by the insurance provider, typically considered either more cost effective or safer, before the insurance company will cover a different service.

After a request comes in from a qualified provider, the request will go through the prior authorization process. The process to obtain prior authorization varies from insurer to insurer but typically involves the completion and faxing of a prior authorization form; according to a 2018 report, 88% are either partially or entirely manual.

At this point, the medical service may be approved or rejected, or additional information may be requested. If a service is rejected, the healthcare provider may file an appeal based on the provider's medical review process. In some cases, an insurer may take up to 30 days to approve a request.

Streamlining the prior authorization process includes standardizing processes for different prior authorization workflows, reducing manual touches, and improving efficiency. Providers should also work closely with payers to ensure that they understand the requirements for each prior authorization. This means capturing the necessary information upfront and securing an agreement from the payer to cover the services. Providers should also track the status of prior authorizations to ensure that they are approved in a timely manner so that payments are not delayed

Insurers have stated that the purpose of prior authorization checks is to provide cost savings to consumers by preventing unnecessary procedures as well as the prescribing of expensive brand name drugs when an appropriate generic is available. In addition, a prior authorization for a new prescription may help prevent potentially-dangerous drug interactions. A 2009 report from the Medical Board of Georgia showed that as many as 800 medical services require prior authorizations.

According to Medical Economics in 2013, physicians have expressed frustration with the current prior authorization process with regards to time spent interacting with insurance providers and the costs incurred based on that time. A 2009 study published in Health Affairs reported that primary care physicians spent 1.1 hours per week fulfilling prior authorizations, nursing staff spent 13.1 hours per week, and clerical staff spent 5.6 hours. A 2012 study in the Journal of the American Board of Family Medicine found that the annual cost per physician to conduct prior authorizations was between $2,161 and $3,430. The cost to health plans was reported at between $10 and $25 per request by 2013. It was estimated in 2009 that prior authorization practices cost the US healthcare system between $23 and $31 billion annually.

A number of legislative and technological developments attempt to optimize the prior authorization process: