Prior authorization denied? What to do next, step by step

What prior authorization is

Prior authorization, also called preauthorization or precertification, is your health plan's approval before you get certain care. Plans often require it for imaging such as MRIs, some surgeries, specialty drugs and some ongoing therapies. Usually your doctor's office sends the request, not you.

Two kinds of denials look similar but mean different things:

• The request was denied. The plan reviewed the request and said no before the care happened.

• No request was on file. The care happened, the claim came in, and the plan denied it because authorization was missing. On an explanation of benefits (EOB), this often appears as reason code 197, which X12, the body that maintains these codes, describes as "precertification/authorization/notification/pre-treatment absent."

The next steps differ, so first work out which one you have.

Step 1: Find out exactly what happened

Call your doctor's office and ask:

• "Did you submit a prior authorization request for this service? On what date?"

• "What did the plan say, and do you have the reference number?"

• "Did the plan ask for more information?"

Then call the plan and ask:

• "Is there an authorization request on file for this service and date?"

• "If it was denied, what was the specific reason?"

• "Is this a final decision, and how do I appeal?"

Sample denial · Northgate Health Plan (synthetic)

Request: MRI, lumbar spine · Requested by: Northgate Spine Clinic · Decision: not approved

Reason: the plan's criteria require six weeks of documented conservative treatment before imaging. Records received show three weeks.

This denial points to a specific gap: documentation of treatment time. The fix may be more records rather than a full argument about medical need.

Step 2: Know the timelines that apply to your plan

Private plans

HealthCare.gov describes these rules for insurers: a written denial of prior authorization within 15 days, or within 72 hours for urgent care. If you appeal, the insurer must decide within 30 days for a service you haven't yet received. Urgent appeals must be decided as quickly as your condition requires, and no later than 4 business days after the request.

Medicare Advantage, Medicaid and CHIP plans

A federal rule from CMS (known as CMS-0057-F) sets prior authorization timelines for Medicare Advantage plans, state Medicaid and CHIP fee-for-service programs, Medicaid managed care plans and CHIP managed care entities. Starting January 1, 2026, these payers must send decisions within 72 hours for urgent requests and within seven calendar days for standard requests. The rule also requires a specific reason for any denied prior authorization. These provisions don't apply to prior authorizations for drugs.

The same rule covers Qualified Health Plans on the federally facilitated exchanges for other purposes, but CMS says they are excluded from these decision timeframes.

Step 3: Choose the right route

Ask for a peer-to-peer review

Some plans let the treating doctor talk directly with the plan's medical reviewer about a denial. Ask your doctor's office whether your plan offers this and whether they will request one.

Resubmit with missing information

If the denial says records were incomplete, ask the office to send the missing documentation, such as treatment notes, test results or a history of what has been tried before. Ask whether it counts as a new request or a reconsideration.

File an internal appeal

If the plan stands by its decision, you can appeal. HealthCare.gov says you generally have 180 days from the denial notice to file an internal appeal. Include:

• the denial letter and reference number;

• a letter from your doctor explaining why the service is needed now;

• the records the plan said were missing;

• the plan's own criteria, if the denial cites them, with a note on how you meet them.

Ask for an expedited appeal if it's urgent

If waiting could seriously harm your health, ask for an expedited review and have your doctor state why it's urgent. HealthCare.gov says that in urgent situations you can ask for an external review at the same time as your internal appeal.

External review

If the internal appeal is denied, HealthCare.gov says you can ask for an independent external review within 4 months of the final denial. The insurer is required by law to accept the external reviewer's decision.

If you already got the care

If authorization was missing and you received the service anyway, ask:

• The provider: "Was authorization your office's responsibility? Can you ask the plan for a retroactive review?" Rules on this vary by plan.

• The plan: "Can this be reconsidered with the medical records?"

• Both: "Am I responsible for this amount under my plan and the provider's contract?" Check the group code next to the denial on your EOB. Under X12's code list, "CO" means contractual obligation and "PR" means patient responsibility. CO points to the provider's contract rather than to you, so ask before you pay an amount marked that way.

Don't ignore the bill while you sort this out. Tell the billing office you're appealing, ask them to note the account, and ask whether collection will pause.

Keep a paper trail

• Save the denial letter, EOB and every message.

• Note each call: date, time, name and what was said.

• Write down reference numbers for the authorization request and the appeal.

• Put the appeal deadline in your calendar.

Get the denial decoded

When EasyToDecode opens, you'll be able to upload a prior authorization denial or the EOB that shows it and see the reason and deadline quoted from the page, with what's missing listed, plus an editable appeal letter and questions for your doctor's office. See how it works or join the waitlist.