CPT code 84460 – Alanine aminotransferase (ALT) test

Key takeaways

CPT code 84460 reports a quantitative ALT (SGPT) test on serum or plasma, distinct from the AST test reported under CPT 84450.

84460 bundles into the CMP (80053) and the hepatic function panel (80076), so billing it separately on the same claim is unbundling under NCCI edits.

Common denial causes include missing ICD-10 medical-necessity codes, no ABN on file for Medicare patients, and modifier errors on repeat same-day testing.

Pabau’s claims management software scrubs each 84460 claim for missing or invalid details, submits it through the Claim.MD clearinghouse, and auto-posts the ERA.

CPT code 84460: Official description and clinical overview

CPT code 84460 is the lab code for a single alanine aminotransferase (ALT) test. It sits in the Chemistry subsection (82009-84999) of the AMA’s Pathology and Laboratory section.

The official AMA descriptor reads Transferase; alanine amino (ALT) (SGPT). It covers one quantitative enzymatic assay of ALT activity in serum or plasma. Clinicians order it to check liver function or to watch for drug-induced liver damage.

ALT and its older synonym SGPT refer to the same analyte. Both terms appear in the AMA’s CPT code set, and either is acceptable in lab order documentation. The test is most often ordered as part of a liver workup, medication monitoring (statins, antiepileptics, antituberculars), or metabolic screening.

What the test measures: ALT (SGPT) and its clinical role

ALT is a liver-specific enzyme that catalyzes the transfer of an amino group from alanine to alpha-ketoglutarate. Elevated serum ALT levels indicate hepatocyte damage because the enzyme leaks from injured liver cells into the bloodstream. It is more liver-specific than AST (CPT 84450), which is also elevated in muscle injury and hemolysis.

Clinicians order CPT code 84460 in several common scenarios.

• Hepatitis screening and monitoring: Elevated ALT is the earliest biochemical marker in acute viral hepatitis A, B, and C.
• Medication toxicity surveillance: Statins, isoniazid, methotrexate, and valproic acid all carry hepatotoxicity risk. ALT monitoring is standard of care.
• Non-alcoholic fatty liver disease (NAFLD): ALT elevation in a metabolic context (obesity, type 2 diabetes) supports the diagnosis of NAFLD or NASH.
• Alcoholic liver disease: ALT is typically elevated but lower than AST in alcoholic hepatitis. The AST:ALT ratio guides diagnosis.
• Pre-operative clearance: Many surgical protocols include a baseline liver panel that incorporates 84460.
• Routine metabolic panel follow-up: When a CMP flags elevated ALT, a standalone repeat test uses CPT code 84460 directly.

CPT code 84460 fee schedule and Medicare reimbursement

The Medicare Clinical Laboratory Fee Schedule (CLFS), maintained by the Centers for Medicare and Medicaid Services (CMS), sets the national rate for CPT code 84460. Always verify the current CLFS rate in the CMS downloadable file before you submit, because the table below gives no 2026 figure.

Lab codes like 84460 are paid from the CLFS, not the physician fee schedule, so an RVU lookup won’t show their payment rate. Check the CLFS file directly.

If your practice builds a superbill for each visit, list the CLFS rate beside the CPT code. Billing staff can then flag a mismatch at entry instead of after adjudication.

CPT 84460 vs 84450: How ALT and AST differ

CPT 84450 (AST/SGOT) and CPT code 84460 (ALT/SGPT) measure different aminotransferases. Both can be billed on the same date of service when independently ordered and clinically indicated. No NCCI column I/II edit bundles the two codes against each other. The confusion arises because they are frequently ordered together in a liver workup and their numeric codes sit adjacent in the chemistry range.

Bundling rules: When CPT code 84460 cannot be billed separately

The National Correct Coding Initiative (NCCI) bundles CPT code 84460 into two panels billed on the same claim. They are the comprehensive metabolic panel 80053 and the hepatic function panel 80076. Billing 84460 separately alongside either panel on the same date of service is unbundling and triggers a CO-97 denial. The Office of Inspector General (OIG) actively monitors unbundling of lab panel components as a fraudulent billing pattern.

• CMP (CPT 80053): Contains ALT (84460), AST (84450), total protein, albumin, bilirubin (total), ALP (84075), BUN, creatinine, glucose, and electrolytes. If the clinician orders an 80053, do not separately bill 84460.
• Hepatic function panel (CPT 80076): Contains ALT (84460), AST (84450), ALP (84075), total protein, albumin, and total and direct bilirubin. The same rule applies.
• Standalone billing is appropriate when only the ALT was ordered, or when the panel falls on a different date of service. A same-day repeat ALT ordered after a CMP for monitoring takes modifier 91.
• Modifier 59 does not override NCCI panel bundling edits for 84460 in the context of 80053 or 80076. Modifier 59 applies to distinct procedural services, not panel component unbundling.

The flow below puts those rules in the order a biller checks them on a live claim.

ICD-10 codes that support medical necessity for CPT 84460

Every claim for CPT code 84460 must link to an ICD-10-CM diagnosis code that justifies the test. Payers use Local Coverage Determinations (LCDs) and National Coverage Determinations (NCDs) to define which diagnoses establish medical necessity. The codes below are commonly accepted. Covered diagnoses vary by payer and change over time, so verify your MAC’s current LCD before you submit. Use the CDC/NCHS ICD-10-CM tool to confirm each code remains active in the current fiscal year.

A diagnosis of “abnormal liver enzymes” or “elevated LFTs” without a specific ICD-10 code is a common documentation shortcut that payers reject. Use R74.01 when a prior panel flagged elevated transaminases and the standalone ALT is a follow-up measurement.

Documentation requirements for billing CPT 84460

A complete chart supports both the claim and any post-payment audit. The ordering provider’s notes, not just the lab requisition, must show why the ALT test was clinically indicated on this date of service. Documentation for CPT code 84460 needs each of the following elements.

• Signed lab order: Written or electronic order from the treating provider, dated and tied to the encounter. Verbal orders must be authenticated promptly per HIPAA-compliant documentation policy.
• Clinical indication: A note entry (problem list, A/P section, or order comment) explaining why ALT monitoring is medically necessary. For example: “monitoring ALT every 3 months while on atorvastatin per ACC/AHA guidelines.”
• Ordering provider NPI: The ordering provider’s NPI must appear on the 837P claim in Loop 2420E, or in Box 17 on the CMS-1500. A missing or incorrect NPI triggers a CO-16 denial.
• Specimen collection date: Box 24A on the CMS-1500 (or equivalent 837P loop). The date of service is the collection date, not the report date.
• Place of service code: 81 (independent laboratory) is most common. POS 11 (office) applies when the physician performs the test in-office.
• ICD-10-CM diagnosis code: At least one code from the accepted list above must link to the CPT on the claim line.

When an ABN is required

An Advance Beneficiary Notice of Noncoverage (ABN) must be signed before CPT code 84460 is performed for some Medicare patients. It applies when the lab expects the test may not meet Medicare’s medical-necessity criteria for that diagnosis. This commonly applies to routine wellness or screening orders where no documented condition supports the test.

An ABN is not required for every Medicare ALT order. It is required when the specific clinical scenario falls outside covered diagnoses in the applicable LCD. Without a signed ABN on file, the lab absorbs the cost if Medicare denies on medical-necessity grounds. It cannot bill the patient.

Common claim denials for CPT 84460 and how to fix them

Most CPT code 84460 denials trace back to five claim adjustment reason codes (CARCs). A structured denial management workflow resolves each one differently. The table below maps each code to its root cause and the corrective action. For the full list, see our guide to medical billing denial codes.

Modifiers for CPT code 84460: When and how to use them

Lab chemistry codes like CPT code 84460 use modifiers sparingly. Two modifiers come up in repeat-testing scenarios. Picking the wrong one, or using either when the panel is the right code, is a leading cause of CO-4 denials.

Modifier 91: Repeat clinical diagnostic laboratory test

Modifier 91 is appropriate when a clinician orders a second ALT on the same date of service to obtain a subsequent result for treatment-management purposes. For example, a patient with suspected acute hepatitis has ALT measured at 8:00 AM. The clinician orders a repeat at 2:00 PM to track the enzyme trajectory over six hours.

Modifier 91 is not permitted when the repeat is ordered because the first specimen was compromised, the equipment malfunctioned, or a testing error occurred. It applies only to clinically motivated repeats.

Modifier 59: Distinct procedural service

Modifier 59 is sometimes erroneously appended to CPT code 84460 in an attempt to override the NCCI bundling edit with CMP (80053). This does not work. The NCCI edit bundling 84460 into 80053 is a “column I/II” edit type that modifier 59 cannot override. Applying modifier 59 in this context triggers a CO-4 denial and, if audited, can support a finding of improper billing. Reserve modifier 59 for distinct procedural services whose NCCI edit carries a modifier indicator of 1.

How to submit a clean claim for CPT code 84460

A clean claim for CPT code 84460 moves through adjudication without manual intervention. Building a clean claim for a lab chemistry code means getting six fields right. Automated edits check them before a human reviewer sees the claim. Submit CPT code 84460 claims electronically as an 837P. Pabau submits claims electronically to thousands of US payers through the Claim.MD clearinghouse.

1. Select the correct code: 84460 for a standalone ALT. If a CMP or hepatic panel was also ordered, bill the panel code only.
2. Link a covered ICD-10 code: Place the diagnosis in Box 21 (CMS-1500) and reference it in Box 24E. Use R74.01, K76.0, Z79.899, or another LCD-approved code for this payer.
3. Report the ordering provider’s NPI: On the 837P it goes in Loop 2420E (ordering provider). On a paper CMS-1500 it goes in Box 17.
4. Set the date of service to specimen collection date: Box 24A. Do not use the date the result was reported.
5. Select the correct place of service: POS 81 (independent lab) or POS 11 (physician office). POS 81 and POS 11 carry different reimbursement rules under some payer contracts.
6. Apply a modifier only if clinically required: Use modifier 91 for a same-day repeat and no modifier for a standard single test. Never use modifier 59 against a panel.

Neighboring lab codes coders often confuse with 84460

Several chemistry codes in the 82xxx-84xxx range are frequently ordered alongside CPT code 84460 in a liver workup. Each needs its own claim line when ordered as a standalone, and each has its own panel-bundling rules.

Use the AAPC Codify CPT lookup to confirm panel inclusion for any chemistry code before billing it alongside 84460.

How Pabau cuts preventable denials on CPT code 84460

Most 84460 denials start before submission, with a panel code on the same claim or a missing ordering NPI. Many practices only find the error when the remittance comes back days later.

Pabau’s claims management software scrubs every claim for missing or invalid details before it leaves your system. Clean claims then go out electronically through the Claim.MD clearinghouse.

When the payer responds, the electronic remittance advice (ERA/835) is auto-posted against the claim. A denied 84460 line arrives with its CARC code attached, so your team can correct and resubmit it inside the timely-filing window.

Catch 84460 claim errors before submission

Pabau’s claim validation flags missing or invalid details on every lab claim, then submits it through Claim.MD and auto-posts the ERA. Your team spends less time reworking denied lines.

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Conclusion

CPT code 84460 is simple to bill once three details line up. The claim needs a covered ICD-10 code, no CMP or hepatic panel on the same date, and the ordering provider’s NPI. Check those before submission and most 84460 denials never happen.

If your team still finds these errors only after the remittance arrives, move the checks earlier in the workflow. The cost of one missed panel conflict is a full resubmission cycle on a low-value lab line. Book a demo to see how Pabau’s claim validation catches those errors before 84460 claims go out.

Continue your research

Need a full primer on how claims move from order to payment? What is revenue cycle management walks through each stage of the billing cycle for labs and physician practices.

Unsure which clearinghouse to use for lab claims? Medical claims clearinghouse guide explains how clearinghouses check claims before they reach the payer.

Want to stop denials before the test is drawn? Insurance eligibility verification covers the payer checks that prevent same-day lab denials at the point of order.

Billing the full liver panel instead? CPT code 80076 covers the hepatic function panel that already includes ALT.

Coding the diagnosis behind a follow-up ALT? ICD-10 code R74.01 covers elevated liver transaminase levels, the most direct medical-necessity code for 84460.

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