CPT code 76497 – Unlisted computed tomography procedure

Key takeaways

CPT code 76497 is the AMA’s unlisted CT procedure code, used only when no specific radiology CPT code covers the service.

A special report describing the procedure, its medical necessity, and the most similar listed code must accompany every claim.

Most commercial payers and Medicaid managed care plans require prior authorization before the CT service is performed. A claim with no authorization number on file is denied.

Pabau, the practice software we build, helps submit claims electronically, track prior-authorization numbers and follow claim status. The special-report checklist stays a practice workflow.

CPT code 76497: official descriptor and code definition

CPT code 76497 is defined by the American Medical Association as “Unlisted computed tomography procedure (eg, diagnostic, interventional).” It sits in the Radiology section of the CPT codebook, in the Diagnostic Radiology range 70010-76499. That range covers X-ray, fluoroscopy, MRI, and CT procedures.

In CPT terminology, “unlisted” only signals that no five-digit code describes that particular CT service yet. An unlisted procedure can still be established, approved, and covered. The AMA uses unlisted codes for services that exist clinically but have no descriptor of their own. That includes novel techniques that post-date the current code cycle.

Key code characteristics at a glance

What CPT code 76497 covers

CPT code 76497 covers any CT-based imaging procedure for which no specific CPT code exists. Three kinds of CT service most often end up here:

• Novel CT protocols: photon-counting CT, dual-energy CT with advanced spectral post-processing, or ultra-high-resolution CT when payer policy does not yet recognize a dedicated code.
• Emerging interventional CT techniques: CT-guided nerve blocks, CT-guided biopsies of unusual sites, or CT fluoroscopy procedures whose site-and-approach combination has no dedicated descriptor.
• CT services with no Category I code: a novel CT technique that has no Category I code and no Category III code. Where a Category III code exists, report it instead of 76497.

Treat 76497 as a last-resort code, and use it only after confirming no specific code matches the service. The AMA’s CPT guidelines are explicit that unlisted codes should not be used when a more specific code is available.

Exclusions and common misuses

The most frequent billing error with CPT code 76497 is using it for a CT procedure that already has a dedicated code. Payer edit engines check for this automatically. When a coder bills 76497 for a service that has its own code, the claim usually denies on the first pass.

Common CT procedures with their own specific codes that must never be billed as 76497:

• CT abdomen without contrast: CPT 74150
• CT abdomen with contrast: CPT 74160
• CT abdomen without and with contrast: CPT 74170
• CT abdomen and pelvis without contrast: CPT 74176
• CT abdomen and pelvis with contrast: CPT 74177
• CT abdomen and pelvis without and with contrast: CPT 74178
• CT chest without contrast: CPT 71250
• CT chest with contrast: CPT 71260
• CT angiography, chest: CPT 71275
• CT angiography, cardiac: CPT 75574
• CT angiography, abdomen and pelvis: CPT 74174

MRI codes (for example 70551 or 72148) are never an alternative to 76497, because MRI is a different imaging modality. Plain radiograph codes and fluoroscopy codes don’t apply to CT services either. Review the full radiology section of the current CPT codebook before concluding that 76497 is appropriate.

CPT 76497 vs. 76499 and the other unlisted imaging codes

CPT 76497 and CPT 76499 are easy to confuse, but each one covers a different imaging modality. Billing the wrong unlisted code gets the claim denied and delays payment.

Identify the imaging modality first, then pick the unlisted code for that modality. If the service used a CT scanner, 76497 is the only correct unlisted option, as the decision path below shows.

Documentation requirements for the special report

Every claim for CPT code 76497 needs a special report attached at the first submission. Payers price unlisted codes by report, so a claim sent without one is likely to be denied for missing documentation.

A complete special report covers five elements. Document all five before you submit, as part of your wider medical billing compliance routine:

1. Procedure description: What CT procedure was performed, how it was conducted (e.g., contrast agent, slice thickness, reconstruction protocol), and the anatomical region imaged.
2. Medical necessity narrative: Why this CT procedure was clinically indicated, linked directly to one or more ICD-10-CM diagnosis codes on the claim.
3. Absence of specific code: A statement that no specific CPT code describes the service as performed. Cite the closest comparable code you reviewed and rejected.
4. Complexity and time: Total imaging time, number of sequences or reconstructions, and any special technical considerations that distinguish this service from standard CT protocols.
5. Physician attestation: A signed statement from the supervising or interpreting radiologist confirming the documentation is accurate and complete.

Add all five elements as required fields to your superbill preparation checklist. The report is then finished before the claim goes out, and nobody has to rebuild it for an appeal.

Prior authorization requirements

Prior authorization is required by virtually all commercial payers and most Medicaid managed care plans for unlisted radiology codes including CPT code 76497. Many large commercial payers delegate imaging authorization to radiology benefit managers (RBMs). eviCore healthcare, NIA/Magellan (now Evolent Health), and Carelon Medical Benefits Management (formerly AIM Specialty Health) make prior-auth decisions for dozens of health plans. Check the patient’s insurance card or the payer portal to determine whether an RBM is involved before initiating the auth process.

• Obtain authorization before scheduling the scan. Performing the CT and then seeking retroactive auth is a losing strategy with almost all payers.
• Reference the most similar specific CPT code in the auth request alongside 76497. RBM reviewers need a benchmark to evaluate clinical equivalency and set a reimbursement basis.
• Attach the clinical rationale upfront. The same medical-necessity narrative required in the special report should accompany the auth request. Submitting it twice (once for auth, once with the claim) is redundant but correct.
• Track the auth number. Every claim for 76497 must carry the prior-authorization reference number in Box 23 of the CMS-1500 form. Missing this triggers an auth-not-on-file denial even when authorization was obtained.

Traditional Medicare (Parts A and B) does not use a standard prior-auth process for radiology in most settings. Medicare Administrative Contractors (MACs) still conduct medical review of unlisted-code claims. The claim still requires a complete special report to pass MAC review.

How to bill CPT code 76497, step by step

Submitting a clean claim for CPT code 76497 requires more preparation than a standard radiology code. Follow these steps in order to improve first-pass acceptance. Steps 5 and 6 are where practice claims management software takes over the manual submission work.

1. Confirm no specific CPT code exists. Search the current year’s CPT codebook radiology section and cross-reference the AAPC CPT code lookup. Document your search in the patient record.
2. Obtain prior authorization. Contact the payer or RBM before the service date. Record the auth number and the name of the reviewer.
3. Assign ICD-10-CM diagnosis codes. Select codes that directly support the medical necessity of the specific CT procedure performed. Weak ICD-10 linkage is a top denial trigger for unlisted-code claims.
4. Complete the CMS-1500 claim form fields specific to 76497. See the table below for the key fields.
5. Attach the special report. For electronic claims, submit the special report as an attachment using the loop 2300 PWK segment (EDI 837P). For paper claims, attach a printed copy and include a cover letter.
6. Submit through your clearinghouse. Pabau sends claims electronically through Claim.MD, its US clearinghouse partner, to thousands of US payers. Our Claim.MD clearinghouse guide covers eligibility checks and claim status tracking.
7. Follow up within payer-specific windows. Medicare requires a 12-month timely-filing window from the date of service. Commercial payers commonly set 90-180 days. Missing timely filing is an unappealable denial.

Key CMS-1500 fields for CPT code 76497 claims

Reimbursement: how payers price an unlisted CT code

CPT code 76497 has no assigned Relative Value Units (RVUs) and no published Medicare Physician Fee Schedule rate. As an unlisted code, reimbursement is determined entirely through individual payer review and is designated “priced by report” (PBR) in the CMS Physician Fee Schedule.

In practice, payers benchmark the 76497 claim against the most similar specific CT code and pay at or near that code’s allowed amount. This is why the special report must explicitly identify the comparable code. A report that says “similar to CPT 74177” gives the payer’s pricing team a starting point. Without a comparison code, the reviewer has to guess, and the guess usually comes in low.

For charge setting, the table below shows 2026 Medicare national non-facility (global) rates for the CT codes most often used as comparators. Each is the total RVU from the CMS relative value file (July 2026) multiplied by the $33.4009 conversion factor.

These are national amounts before the Geographic Practice Cost Index (GPCI) adjusts them by locality. Qualifying APM participants are paid at a slightly higher conversion factor of $33.5675. Confirm local figures through the CMS fee schedule lookup or your MAC’s published rates.

Medicare coverage for CPT 76497

No National Coverage Determination (NCD) or Local Coverage Determination (LCD) sets specific coverage criteria for CPT code 76497 itself. Coverage is decided by the Medicare Administrative Contractor (MAC) through individual claim review.

For a MAC to approve a 76497 claim, the documentation must satisfy three conditions:

• Medical necessity established: The CT procedure must be reasonable and necessary for the patient’s diagnosis or treatment. ICD-10-CM codes and clinical documentation in the medical record support it.
• No specific code applies: The claim must demonstrate that no existing CPT code describes the service. A coder attestation or a written explanation in the special report is required.
• Not experimental: The procedure must not be classified as investigational under Medicare. If the CT technique is part of a clinical trial, coverage may be available under Medicare’s Clinical Trial Policy. Separate coverage rules and a different claim process apply.

Medicare Advantage plans (Part C) follow their own coverage policies, which may be stricter than Traditional Medicare. Confirm coverage and prior-auth requirements directly with the specific plan before performing the service.

Why 76497 claims are denied and how to prevent it

Every unlisted-code claim goes to manual review, so CPT code 76497 claims are denied more often than claims for specific CT codes. Systematic denial management workflows and familiarity with medical billing denial codes help teams catch issues before they become recoupments.

How to appeal a denied claim

Most denied 76497 claims are recoverable on first-level appeal when the denial is documentation-based. A missing special report or an inadequate medical necessity narrative is fixable; a timely-filing denial generally is not.

1. Identify the denial reason code. Read the Remittance Advice remark codes (CARCs and RARCs). Common codes for unlisted procedures include CO-4 (service inconsistent with modifier), CO-97 (bundled), and N519 (invalid combination of HCPCS modifiers).
2. Draft the appeal letter. State the clinical rationale, confirm no specific CPT code exists, and cite AMA CPT guidelines for unlisted-code use. Attach the updated or original special report.
3. Reference the comparable specific code. State the most similar listed CPT code and explain why that code does not fully describe the service performed. This gives the payer a reimbursement benchmark and demonstrates due diligence.
4. Request peer-to-peer review for clinical denials. When a payer denies on medical necessity grounds, the interpreting radiologist should request a peer-to-peer call with the payer’s medical director. These calls resolve a meaningful proportion of clinical-criteria denials.
5. Track your deadlines. Medicare redetermination requests must be filed within 120 days of the initial denial remittance date. Commercial payer appeal windows vary; most fall between 30 and 180 days. Missing the window forfeits the appeal right.

How claims management software keeps 76497 claims on track

Radiology billing teams often track 76497 claims across a payer portal, a spreadsheet of auth numbers, and a folder of special reports. Each handoff is a chance for the auth number to drop off the claim.

Pabau turns the invoice into an electronic CMS-1500 claim and sends it through Claim.MD to thousands of US payers. Your team can track the prior-authorization number against each claim and follow its status in the same billing workflow.

The special-report checklist stays a practice workflow, and your coders still confirm that no listed code fits. What changes is the follow-up. A claim stuck in manual review shows up in claim status long before the timely-filing deadline.

Keep unlisted CT claims moving

Pabau helps your team submit 76497 claims electronically, track prior-authorization numbers, and follow each claim’s status until it’s paid.

Book a demo

Conclusion

Billing CPT code 76497 well comes down to the work done before the scan. Confirm that no Category I or III code fits, secure the authorization, and write the special report against the closest comparable code. Done that way, novel CT work gets paid at a defensible rate. Used as a shortcut for listed procedures, the code brings denials and audit exposure.

The trade-off is time, because each 76497 claim takes more coder and radiologist effort than a listed code. Reserve it for services that need it. Pabau’s clean claim submission workflows help you submit claims electronically to thousands of US payers, track prior-authorization numbers and follow claim status. Book a demo to see how Pabau keeps your unlisted CT claims moving from submission to payment.

Continue your research

Need to understand how clearinghouse submission works for complex codes? Our Claim.MD clearinghouse guide explains how electronic claim routing works for unlisted and specialty codes.

Want to reduce denials before they happen? Understanding electronic remittance advice covers how to read ERA files and identify denial patterns early.

Looking for an overview of the claims filing process? The 837 file guide walks through EDI claim submission for radiology and specialty practices.

Frequently asked questions