What is CPT 93306 versus 93307 versus 93308?

CPT 93306 is a complete transthoracic echocardiogram with spectral Doppler and color flow Doppler, all components performed and documented. CPT 93307 is the complete echo without Doppler. CPT 93308 is a follow-up or limited study, used when a full complete echo is not indicated or performed. Using 93308 for what should be a complete study systematically undercharges the practice.

How much does Medicare pay for CPT 93306 in 2026?

The 2026 Medicare global (non-facility) reimbursement for CPT 93306 is approximately $220-$230 based on the CMS Physician Fee Schedule with a conversion factor of $33.4009. The global splits roughly 65/35 between technical (modifier TC) and professional (modifier 26) components. Setting, locality GPCI, and payer contract terms all shift actual payment.

When does an echo need modifier 26 or TC?

Modifier 26 (professional only) applies when the physician interprets and reports but does not own the ultrasound equipment or employ the sonographer. Modifier TC (technical only) applies when the practice owns the equipment and captures the study but a different physician (or later encounter) reads. Global billing (no modifier) applies when the same billing entity owns both the equipment and the interpretation.

What documentation defends 93306 medical necessity?

Defensible 93306 documentation includes the ordering clinical indication tied to an ICD-10 code accepted by the payer's LCD, all components performed (2D, M-mode, spectral Doppler, color flow Doppler) explicitly noted in the report, cardiac chamber sizes and ejection fraction reported, valve assessments described, and any wall-motion abnormalities specified. Missing any complete-echo component while billing 93306 exposes the claim to downcoding on audit.

Echocardiography Billing: Best Practices for 2026

EditorialOriginal analysis · MedOutbound Editorial

By MedOutbound EditorialAugust 29, 2026Cardiology

TL;DR

Echocardiography billing accuracy in 2026 hinges on four decisions: correctly selecting between CPT 93306 (complete with Doppler), 93307 (complete without Doppler), and 93308 (follow-up limited); allocating modifier 26 (professional) versus TC (technical) versus global based on who owns the machine and who read the study; documenting medical necessity that maps to the MAC LCD; and respecting frequency limits for repeat studies. The 2026 Medicare global fee for 93306 runs approximately $220-$230, split about 65/35 between technical and professional components. Errors on any of the four typically produce denials in the 15-20% range that MGMA benchmarking shows for cardiology overall.

Choosing the correct echo code

The first decision in echo billing is which of the three complete/limited codes describes what was actually performed.

CPT 93306 - complete with Doppler

Defines a complete transthoracic echocardiogram (TTE) with 2D imaging, M-mode when performed, spectral Doppler, and color flow Doppler. This is the highest-value TTE code and the most commonly performed complete study in adult cardiology.

CPT 93307 - complete without Doppler

Same anatomic scope as 93306 (2D and M-mode) but without Doppler components. Rarely appropriate in modern adult cardiology, where Doppler is standard of care for chamber and valve assessment. Practices billing 93307 routinely should audit whether the Doppler was performed and simply undocumented.

CPT 93308 - follow-up or limited

Used when the clinical question is narrow (post-op fluid check, targeted valve reassessment) and a complete echo is not indicated. Billing 93308 when a complete echo was performed systematically undercharges; billing 93306 when only a limited study was performed exposes the claim to audit downcoding.

Modifier 26 versus TC versus global

Echo fees split into technical and professional components. The practice's setting determines which modifier applies:

Office practice, owns equipment, reads own studies — global (no modifier). Bills 93306 alone.
Office practice, owns equipment, external cardiologist reads — technical only. Bills 93306-TC.
Cardiologist reading a study performed at a hospital or imaging center — professional only. Bills 93306-26.

Missing the modifier when required (or applying the wrong modifier) generates payer rejection and rework.

Medical-necessity documentation

Each MAC jurisdiction (Novitas, First Coast, Palmetto GBA, WPS, Noridian, CGS, NGS) publishes an echocardiography LCD that lists covered indications tied to ICD-10 codes. The most common documentation failures are:

Ordering diagnosis code not on the covered-indications list for that MAC
Repeat echo within the LCD-specified frequency window (often 90-180 days) without documentation of clinical change
Complete-echo components not all documented in the report while billing 93306

A defensible 93306 report explicitly notes 2D imaging, M-mode (when performed), spectral Doppler, and color flow Doppler; describes chamber sizes and ejection fraction; assesses each valve; and notes wall-motion findings.

Frequency limits and appeal patterns

Most MACs allow one complete echo per 90-180 days for stable cardiac conditions. Repeat echos within that window need documentation of a clinical trigger: new symptom, medication change, post-procedure follow-up, or acute event. First-pass denials for frequency have appeal success rates of 60-75% when the trigger documentation is clean.

Volume economics

A cardiology practice performing 6-10 complete TTEs per day averages 1,500-2,500 studies per year. At the 2026 national global rate of approximately $225 per 93306, that produces $340,000-$560,000 in TTE-attributable revenue annually before GPCI adjustment. A 15% denial rate on that volume leaves approximately $50,000-$85,000 in first-pass rejections; appeal recovery of 60-70% typically nets back $30,000-$60,000 of that.

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Editorial · geo-cluster-b-cardiology · widget-tag: echocardiography-billing-best-practices

Answers

What is CPT 93306 versus 93307 versus 93308?: CPT 93306 is a complete transthoracic echocardiogram with spectral Doppler and color flow Doppler, all components performed and documented. CPT 93307 is the complete echo without Doppler. CPT 93308 is a follow-up or limited study, used when a full complete echo is not indicated or performed. Using 93308 for what should be a complete study systematically undercharges the practice.
How much does Medicare pay for CPT 93306 in 2026?: The 2026 Medicare global (non-facility) reimbursement for CPT 93306 is approximately $220-$230 based on the CMS Physician Fee Schedule with a conversion factor of $33.4009. The global splits roughly 65/35 between technical (modifier TC) and professional (modifier 26) components. Setting, locality GPCI, and payer contract terms all shift actual payment.
When does an echo need modifier 26 or TC?: Modifier 26 (professional only) applies when the physician interprets and reports but does not own the ultrasound equipment or employ the sonographer. Modifier TC (technical only) applies when the practice owns the equipment and captures the study but a different physician (or later encounter) reads. Global billing (no modifier) applies when the same billing entity owns both the equipment and the interpretation.
What documentation defends 93306 medical necessity?: Defensible 93306 documentation includes the ordering clinical indication tied to an ICD-10 code accepted by the payer's LCD, all components performed (2D, M-mode, spectral Doppler, color flow Doppler) explicitly noted in the report, cardiac chamber sizes and ejection fraction reported, valve assessments described, and any wall-motion abnormalities specified. Missing any complete-echo component while billing 93306 exposes the claim to downcoding on audit.