G0398 HCPCS code: Home sleep study test (hst) with type ii portable monitor, unattended; minimum of 7 channels: eeg, eog, emg, ecg/heart rate, airflow, respiratory effort and oxygen saturation

G0398 is the HCPCS Level II code for home sleep study test (hst) with type ii portable monitor, unattended; minimum of 7 channels: eeg, eog, emg, ecg/heart rate, airflow, respiratory effort and oxygen saturation. In 2024 Medicare paid an average of $98.98 per service for G0398 across 6,642 services. Its Medicare coverage code is C (Carrier judgment): Coverage is decided by the Medicare contractor (MAC) case by case. The NCCI unit limit is 1 per day on outpatient hospital claims. Medicare volume rose 52% from 2022 to 2024 (4,361 to 6,642 services). In 2024, about 323 clinicians billed Medicare for G0398 for 5,726 beneficiaries; North Carolina, Florida, Texas accounted for 43% of services.

Code details

FieldValue
SectionG codes — Procedures and professional services (temporary)
Coverage codeC — Carrier judgment
Pricing indicator13
BETOS categoryT2D
Added2008-03-13
Last action effective2008-03-13

Who bills G0398 (2024)

MeasureValue
Clinicians billing (by place of service)323
Medicare beneficiaries5,726
States with claims28
Share of services in top 3 states (North Carolina, Florida, Texas)43%

Counts only. Supplier and clinician names, contact lists and state-by-state detail are in Caduvo.

Medicare utilization for G0398, 2022–2024

YearServicesBeneficiariesAvg. allowedAvg. paid
20224,3613,962$133.92$102.87
20235,9175,271$132.39$101.40
20246,6425,726$129.28$98.98

States with the most G0398 services (2024)

StateServicesAvg. paid
North Carolina1,132$38.79
Florida868$97.86
Texas815$99.61
California621$137.39
Ohio574$200.72

NCCI unit limits (MUE)

Claim typeMax units per dayRationale
outpatient hospital claims1Code Descriptor / CPT Instruction
practitioner claims1Code Descriptor / CPT Instruction

Medicare policy articles for this code

Covered diagnoses (87 ICD-10-CM codes)

The diagnoses most often listed as covered in the policy articles above:

ICD-10-CMDiagnosisArticles listing it
G47.10Hypersomnia, unspecified6
G47.11Idiopathic hypersomnia with long sleep time6
G47.12Idiopathic hypersomnia without long sleep time6
G47.30Sleep apnea, unspecified6
G47.31Primary central sleep apnea6
G47.33Obstructive sleep apnea (adult) (pediatric)6
G47.34Idiopathic sleep related nonobstructive alveolar hypoventilation6
G47.35Congenital central alveolar hypoventilation syndrome6
G47.36Sleep related hypoventilation in conditions classified elsewhere6
G47.411Narcolepsy with cataplexy6

Showing 10 of 87. The full list, non-covered diagnoses and CSV export are in Caduvo.

What changed for G0398

Frequently asked questions

What is HCPCS code G0398?

G0398 is the HCPCS Level II code for home sleep study test (hst) with type ii portable monitor, unattended; minimum of 7 channels: eeg, eog, emg, ecg/heart rate, airflow, respiratory effort and oxygen saturation. Short descriptor: "Home sleep test/type 2 porta".

How much does Medicare pay for G0398?

In 2024, the average Medicare payment was $98.98 per service (average allowed $129.28).

Does Medicare cover G0398?

Coverage code C — Carrier judgment. Coverage is decided by the Medicare contractor (MAC) case by case.

Which diagnoses support coverage for G0398?

Medicare policy articles that cite G0398 list 87 covered ICD-10-CM diagnosis codes across 8 articles. The most cited include G47.10 (Hypersomnia, unspecified), G47.11 (Idiopathic hypersomnia with long sleep time), G47.12 (Idiopathic hypersomnia without long sleep time). A listed diagnosis is necessary but not sufficient; the policy's other criteria still apply.

How many units of G0398 can be billed per day?

1 on outpatient hospital claims; 1 on practitioner claims (NCCI medically unlikely edits).

Related G03 codes

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Next steps

Sources: CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule; CMS NCCI MUE tables; CMS Medicare utilization (physician and DME supplier files); CMS Medicare Coverage Database articles. Fees are Medicare allowables, not commercial rates. Not billing or legal advice.

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