CPT Code 93306: Description, Billing and Payment (2026)

CPT 93306 reports a complete transthoracic echocardiogram (TTE) with real-time 2D imaging, M-mode when performed, spectral Doppler and color flow Doppler. Because both types of Doppler are built into the code, the separate Doppler codes 93320, 93321 and 93325 are not reported with it, and the study must be complete for the code to apply.

Echocardiography is one of the most frequently billed cardiac imaging services, and it is also a common focus of payer edits and reviews. Most problems come from picking the wrong echo code for the study actually performed, splitting the professional and technical components incorrectly, or weak medical necessity documentation. This guide covers the code family, documentation, modifiers and payment basics for 2026.

CPT 93306 Code Description

CPT 93306 describes a transthoracic echocardiogram, real-time with image documentation (2D), including M-mode recording when performed, complete, with spectral Doppler echocardiography and with color flow Doppler echocardiography. “Complete” means the study evaluates the cardiac chambers, valves, great vessels and pericardium as fully as the patient’s anatomy and image quality allow, with the findings documented in the report.

The Transthoracic Echo Code Family

Doppler add-on codes 93320, 93321 and 93325 may be reported with 93307 or 93308 when Doppler is performed, but not with 93306. Stress echocardiography (93350 and 93351) and transesophageal echocardiography (93312 and related codes) have their own codes.

Documentation Requirements

The report is what supports the code. A clean 93306 claim usually rests on a report that includes:

• The clinical indication for the study, in specific terms.
• 2D evaluation of all chambers, valves, great vessels and the pericardium, with measurements.
• Spectral Doppler and color flow Doppler findings, with key velocities and gradients where relevant.
• Comments on image quality and any structures that could not be adequately seen.
• A signed interpretation with findings and conclusions by the interpreting physician.
• Images retained according to the facility’s policy.

If the study was stopped early or only part of the heart was evaluated, it is not a complete study. Bill 93308, or 93307 with the appropriate Doppler add-ons, based on what was actually performed.

Medical Necessity and Diagnosis Coding

Echocardiograms must be reasonable and necessary for the patient’s condition. Some Medicare Administrative Contractors publish local coverage determinations or billing articles for TTE, so check your MAC’s current policy. Common indications include:

Use the most specific code the documentation supports. For chest pain, our chest pain ICD-10 code guide explains the R07 options. Abnormal echo findings may lead to further testing, such as a 93458 diagnostic cardiac catheterization.

Modifiers for CPT 93306

When the physician practice owns the equipment and provides the interpretation, the global service is billed with no modifier. In a hospital outpatient setting, the physician bills 93306-26 and the hospital bills the technical service on its institutional claim.

How Medicare Pays for 93306

Medicare pays 93306 under the Physician Fee Schedule using relative value units, the payment locality’s geographic adjustments and the conversion factor, which is $33.4009 in 2026 for clinicians who are not qualifying APM participants. Payments are also reduced by the 2% sequestration adjustment. The American Society of Echocardiography’s CY2026 rate comparison lists a national amount of about $197.85 for the global service, $67.51 for the professional component and $130.34 for the technical component. Your actual allowed amount depends on your locality, so check the CMS Physician Fee Schedule look-up tool for your MAC and locality.

Commercial payment depends on each contract. Compare remittances with your contracted rates, and treat the difference between your charge and the allowed amount as a contractual adjustment, not a loss.

Prior Authorization

Original Medicare does not generally require prior authorization for a transthoracic echocardiogram. Many Medicare Advantage and commercial plans manage cardiac imaging through their own utilization programs or radiology benefit managers, and requirements differ by plan and site of service. Verify authorization requirements during eligibility checks, before the study is scheduled.

Worked Example: Hospital Outpatient Echo

A cardiologist in a private group reads a complete TTE performed in a hospital’s outpatient echo lab for a patient referred with a new murmur and shortness of breath.

1. Code selection. The report documents a complete 2D study with spectral and color flow Doppler: 93306.
2. Component. The hospital owns the equipment and employs the sonographer, so the cardiologist bills 93306-26 with POS 22.
3. Diagnosis. The report confirms moderate aortic stenosis, so the claim lists I35.0 as primary and R06.02 as secondary.
4. No extra Doppler codes. 93320 and 93325 are not added, because Doppler is included in 93306.
5. Hospital side. The hospital bills the technical service on its own institutional claim.

Common 93306 Billing Errors

• Billing 93306 for a study that was not complete.
• Adding separate Doppler codes to 93306.
• Billing the global service when the hospital owns the equipment.
• Using an unspecified diagnosis when the report supports a specific one.
• Missing authorization for plans that require it.

Billing 93306 With Other Cardiac Services

A complete echo is often performed alongside other cardiac services, and each pairing has its own rules. An E/M visit on the same day is billed separately only when it is significant and separately identifiable from the decision to order the echo. Myocardial strain imaging (+93356) is reported in addition to 93306 when it is performed and documented. A stress echocardiogram (93350 or 93351) is a different service and is not reported as 93306 plus a stress test. When a contrast agent is used for image enhancement, the agent is reported with its HCPCS code where the payer allows it. Check National Correct Coding Initiative edits before billing any pair of cardiac imaging codes on the same date. Our overview of echocardiogram CPT codes lists the related transthoracic, transesophageal and stress echo codes in one place.

Repeat Studies and Frequency

Medicare does not set a single fixed frequency limit for transthoracic echocardiograms. Instead, each study must be reasonable and necessary based on the patient’s condition at the time. A repeat study is usually supported when there is a change in symptoms or clinical status, a change in therapy that needs to be assessed, or a known condition such as valve disease that needs periodic follow-up. A repeat study ordered only on a routine schedule, without a documented reason, is more likely to be denied.

When a repeat study is needed, the order and the report should state why. If the follow-up question is narrow, such as checking an effusion, a limited study (93308) may describe the work more accurately than another complete study.

Frequently Asked Questions