Prior Authorization

Medicare Denied Claim: Prior Authorization Expired

Name: Medicare Denied Claim: Prior Authorization Expired
Creator: Barley Billing Team
Published: 2026-03-26

Written by Barley Billing Team, Medicare Billing Experts | Last reviewed March 26, 2026

Does your notice say something like this?

"The authorization number is missing, invalid, or does not apply to the billed services"

"Precertification/authorization/notification absent"

"The authorization for this service has expired"

"The service provided does not match the authorized service"

If so, you're in the right place. Here's what it means and what to do.

What This Means

Your claim was denied because the prior authorization on file either expired before the service was provided or didn’t match the service that was actually performed. Even though your plan originally approved something, the approval wasn’t valid for what was ultimately billed.

This is a common issue when there are scheduling delays or when the service delivered differs from what was originally authorized.

Why This Happens

The authorization expired before your appointment. Prior authorizations have an expiration date. If your appointment was delayed beyond that date, the authorization is no longer valid. Common validity periods range from 30 to 90 days.
The service performed was different from what was authorized. If the surgeon authorized a procedure on your left knee but operated on your right knee, or if a different procedure was performed than what was approved, the authorization won’t match.
The claim used different billing codes than the authorization. Even if the service was the same, a mismatch between the CPT or HCPCS codes on the authorization and the claim can cause a denial.
More units or sessions were provided than authorized. If your authorization covered 6 physical therapy visits but you had 8, the extra visits may be denied.
The service was provided by a different provider. Some authorizations are specific to a particular provider. If you saw a different doctor or went to a different facility, the authorization may not apply.
Administrative delays in scheduling. Long wait times for specialist appointments or surgical scheduling can push the service date past the authorization expiration.

Should You Appeal?

Appeal outlook: Weak

Expired or mismatched authorizations are difficult to appeal successfully because the plan’s approval had specific terms that weren’t met. However, there are situations where an appeal may be worth pursuing:

The delay was caused by the plan or provider. If you couldn’t schedule the service within the authorization window because of long wait times or the plan’s own processing delays, document this in your appeal.
The mismatch is minor. If the service was essentially what was authorized but a coding difference triggered the denial, your provider may be able to correct the billing codes and resubmit.
The service was medically urgent. If your condition worsened during the authorization period and a different procedure was medically necessary, your doctor can document why the change was required.

If the authorization simply expired due to scheduling and the plan had no role in the delay, the appeal is unlikely to succeed. Your provider may need to request a new authorization instead.

What To Do Next

Contact your provider’s billing office. Ask them to review the authorization details and the claim. If the issue is a coding mismatch, they may be able to correct the claim and resubmit it.
Check the authorization letter. Review the expiration date, approved services, and any conditions listed. This will help you understand exactly why the claim didn’t match.
Ask your provider to request a new authorization if needed. For future services, a new prior authorization can be obtained. For the already-denied service, you’ll need to appeal.
If you appeal, document the timeline. Show when the authorization was issued, when you tried to schedule the service, and why there was a delay. Include any evidence that the delay was outside your control (appointment wait lists, cancellation notices, etc.).
For Medicare Advantage plans, note that under CMS rules finalized for 2026, approved authorizations must remain valid for the entire approved course of treatment. If your plan cut short an authorization for ongoing treatment, this rule may help your appeal.

Sources

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Appeal Deadlines — Check Your Notice for Exact Dates

Original Medicare

120 days from the date on your MSN

Medicare Advantage

At least 60 days (check your denial notice for exact deadline)

Not sure which you have? Check the top of your denial notice. If it names a private insurance company (like Humana, UnitedHealthcare, or Aetna), you have Medicare Advantage. If it says "Centers for Medicare & Medicaid Services," you have Original Medicare.

Frequently Asked Questions

How long is a prior authorization valid?

It depends on your plan and the type of service. Some authorizations are valid for 30 days, others for 60 or 90 days. Under new CMS rules for 2026, Medicare Advantage plans must honor approved authorizations for the entire course of treatment, even if you change plans. Check your authorization letter for the specific expiration date.

Can my provider get a new authorization?

Yes. If the original authorization expired, your provider can request a new one for the same service. However, the new authorization won't cover the date of service that was already denied. The previously denied claim would need to be appealed separately.

What if the service was delayed for reasons outside my control?

If the service was delayed because of scheduling issues at the provider's office, a hospital backlog, or other factors you couldn't control, mention this in your appeal. Some plans will consider extenuating circumstances, though there's no guarantee.

What does it mean that the authorization didn't match the service?

The prior authorization may have been approved for a different procedure, a different body part, a different provider, or fewer units than what was actually billed. Even small mismatches (like the wrong CPT code) can trigger a denial.

Want Us to Check Your Denial?

Send us your denial notice and we'll review it for free. We'll tell you if it's worth appealing and exactly how to do it.

This information is for educational purposes only and is not legal or medical advice. Always verify with your doctor's office and insurance company.