CPT code 74420 – Retrograde urography with or without KUB

Key takeaways

CPT code 74420 covers retrograde urography with or without KUB, inside the Diagnostic Radiology range 70010-79999.

Radiological supervision and interpretation is included in the global service and is never billed separately.

Modifier 26 covers the radiologist’s professional component, and Modifier TC covers the facility’s technical component.

74420 and CPT 52005 are separately billable, so the urologist bills 52005 while the radiologist bills 74420-26.

Practice management software like Pabau tracks modifiers and payer rules, which cuts manual entry errors on split-billing claims.

CPT code 74420: Official description and procedure category

CPT code 74420 is published by the American Medical Association under the Diagnostic Radiology section of the CPT code set (range 70010-79999). The complete official descriptor reads: Urography, retrograde, with or without KUB.

The procedure involves a urologist placing a ureteral catheter during cystoscopy and injecting radiopaque contrast in a retrograde direction, up toward the kidneys. A radiologist then supervises the imaging and interprets the study. That supervision and interpretation component is bundled into the global service, so it is never billed as a separate add-on.

Clinical indications and medical necessity for retrograde urography

Payers require documented clinical indications before approving a retrograde urography claim. A vague order note does not satisfy medical necessity review. The indication must be specific enough that an auditor can confirm the procedure was clinically appropriate for that patient on that date.

Payers routinely audit high-cost radiology imaging, and retrograde urography without a clear clinical trigger is a common prepayment review target. Accepted indications include:

• Ureteral obstruction – suspected stone, stricture, or extrinsic compression where other imaging is inconclusive
• Hematuria workup – gross or microscopic hematuria requiring upper tract evaluation
• Ureteral injury assessment – post-surgical or traumatic injury evaluation
• Surveillance for transitional cell carcinoma – upper tract monitoring following prior urothelial malignancy
• Filling defect evaluation – characterization of a defect seen on prior CT urogram or IVP

Each of these requires a corresponding ICD-10-CM diagnosis code on the claim. Mismatches between the stated indication and the diagnosis code trigger automated denials before a human reviewer ever sees the chart.

Modifiers 26 and TC: Professional and technical components

The most consequential billing decision for CPT code 74420 is how to handle the split service. The urologist places the catheter and injects the contrast. The radiologist supervises the imaging and interprets the results. Getting the split wrong produces denials that are hard to correct after the fact.

In a hospital outpatient setting, the radiologist bills 74420-26 and the hospital bills 74420-TC. A freestanding radiology group that owns the equipment and employs the interpreting radiologist bills 74420 globally, with no modifier. The urologist never bills 74420 directly, because the catheter placement and contrast injection are captured by the cystoscopy code.

The routing below follows from a single question, which is who owns the imaging equipment.

2026 Medicare reimbursement and fee schedule for CPT 74420

Medicare reimburses CPT code 74420 through the Medicare Physician Fee Schedule (MPFS), which CMS updates annually each January. Rates vary by geographic payment locality. Verify the national averages below against the CMS Physician Fee Schedule lookup tool for the locality where services are rendered.

Billing teams submit CPT code 74420 claims electronically and reconcile payment from the 835 remittance advice. Practice management software like Pabau routes those transactions through Claim.MD, our clearinghouse partner, which reaches thousands of US payers and returns real-time eligibility checks.

The 2026 rates have to come from the MPFS search tool itself, because third-party fee schedule aggregators may not carry final locality adjustments. The FastRVU 2026 RVU lookup is useful for the national work, practice expense, and malpractice RVU values, which are not locality-adjusted. Cross-check the payment rate against the CMS source before you bill.

Billing 74420 alongside CPT 52005 for cystoscopy

The most common billing scenario for CPT code 74420 pairs it with CPT 52005, cystoscopy with ureteral catheterization. The urologist performs the cystoscopy and the catheter insertion, which 52005 covers. The radiologist supervises the imaging and interprets the retrograde urogram, billed as 74420-26 in a facility setting.

These two codes are separately billable because they represent distinct services performed by different providers. CPT 52005 is not bundled with CPT code 74420 under National Correct Coding Initiative edits. Both can appear on the same date of service without a modifier override.

Occasionally one physician performs the catheterization and also interprets the images, which happens in some outpatient surgery centers. The global 74420 applies in that case. When the roles are split, verify which entity owns the imaging equipment before assigning modifiers.

Related CPT codes and the ICD-10-CM diagnosis crosswalk

Selecting the wrong ICD-10-CM code is the second most common cause of CPT code 74420 claim failure. The diagnosis must directly support the clinical indication documented in the procedure report.

Our ICD-10-CM code reference carries the full descriptor and chapter placement for each of these diagnoses. Verify every code against the current fiscal year code set published by CDC/NCHS. The N13.x and R31.x ranges have been stable in recent update cycles, but annual review is still required.

NCCI bundling edits and billing rules

CMS updates National Correct Coding Initiative edits quarterly. The edits relevant to CPT code 74420 reflect the procedure’s structure. Because 74420 covers radiological supervision and interpretation, codes that duplicate that service are bundled and cannot be billed separately.

Check the current NCCI tables rather than a static reference. Edit pairs change, so a bundling rule that did not exist last quarter may apply today. Remittance messages name the edit that fired, which tells revenue cycle staff whether an appeal is worth filing.

• Bundled with 74420: Separate billing for radiological supervision and interpretation when already included in the global service is not payable
• Modifier override available: Some NCCI edits on 74420 can be overridden with a modifier when clinical documentation supports separate, distinct services
• 52005 is not bundled with 74420: These two codes describe services performed by different providers, and no NCCI edit bundles them together
• Quarterly review required: Verify current edit status through the CMS NCCI tables before submitting claims involving 74420 with other radiology or urology codes

Documentation requirements for a 74420 claim

Complete documentation is what converts a technically correct code selection into a paid claim. For CPT code 74420, the record must let an auditor verify medical necessity. It also has to identify the provider who performed each component and confirm that contrast was used retrograde.

The charge ticket should capture the referring provider, the performing provider (urologist), and the interpreting provider (radiologist) as distinct fields. A ticket that names only one physician forces the biller to guess which component to bill.

• Clinical indication: The ordering provider’s documented reason for requesting retrograde urography, tied to a specific ICD-10-CM code
• Procedure report: Operative or procedure note confirming catheter placement, contrast injection route (retrograde), and any KUB imaging acquired
• Contrast documentation: Type of contrast agent used and any adverse reaction monitoring
• Radiologist interpretation report: A signed, dated interpretation of the images with findings and impression, which is the deliverable that justifies the 74420-26 professional component
• Ordering provider information: Name and NPI of the provider who ordered the procedure
• Setting designation: Clear identification of whether the service was performed in a facility or non-facility setting, which determines the applicable fee schedule rate

The interpretation report is the document payers scrutinize most closely on audit. A brief addendum to an operative note is not a substitute. Payers want a standalone radiology interpretation report, signed by the interpreting physician.

Common billing errors and how to avoid them

CPT code 74420 generates a predictable set of billing errors, and the same five account for most of them. Working through them at charge entry reduces rework and shortens the time to payment for radiology and urology teams.

Categorizing these errors before they become denials is the whole point of a charge-entry check. The clean claim standards that govern first-pass payment catch all five at that stage.

How practice management software supports retrograde urography billing

The billing errors above share one root cause. Manual charge entry is applied to a code that needs two providers to coordinate. When the urology team and the radiology team each enter charges without a shared system to flag modifier requirements, errors multiply.

Pabau’s rules-driven claims management checks each charge against payer-specific rules as it is entered. A 74420 submitted in a facility setting without Modifier 26 is flagged before the claim leaves the practice. Claim.MD, our clearinghouse partner, then handles real-time eligibility verification and 835 ERA reconciliation across thousands of US payers.

Revenue cycle managers can track CPT code 74420 claim performance through practice-level reporting rather than relying on static fee schedule tables.

Connecting charge capture to the clearinghouse removes the manual steps between code selection and a paid claim. That matters most in split-billing scenarios, which is exactly what 74420 creates.

Streamline urology and radiology billing with Pabau

Pabau’s claims management workflows support modifier tracking, payer-specific rule sets, and clearinghouse integration. Split-billing scenarios like 74420 and 52005 move from charge capture to paid claim with fewer manual steps.

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Conclusion

CPT code 74420 is a straightforward code with three points where billing goes wrong. They are modifier assignment in facility settings, the urologist-radiologist service split, and ICD-10 specificity on medical necessity. Get those three right and most claims pay on first submission.

The costly decision is made before the claim is built. Confirm who owns the imaging equipment and who signs the interpretation report, and the modifier follows from that.

For practices handling high volumes of retrograde urography billing, connecting charge capture to clearinghouse submission with payer-rule validation removes most of the rework. Book a demo to see how Pabau handles split billing across urology and radiology.

Continue your research

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Want to reduce claim rejections before they reach the payer? Clean claim submission standards outlines the pre-submission checks that prevent the most common billing errors.

Building a denial management process for your urology or radiology practice? Denial management in healthcare explains how denials are categorized, appealed, and prevented across payer types.

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