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
| Field | Value |
|---|---|
| Section | G codes — Procedures and professional services (temporary) |
| Coverage code | C — Carrier judgment |
| Pricing indicator | 13 |
| BETOS category | T2D |
| Added | 2008-03-13 |
| Last action effective | 2008-03-13 |
Who bills G0398 (2024)
| Measure | Value |
|---|---|
| Clinicians billing (by place of service) | 323 |
| Medicare beneficiaries | 5,726 |
| States with claims | 28 |
| 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
| Year | Services | Beneficiaries | Avg. allowed | Avg. paid |
|---|---|---|---|---|
| 2022 | 4,361 | 3,962 | $133.92 | $102.87 |
| 2023 | 5,917 | 5,271 | $132.39 | $101.40 |
| 2024 | 6,642 | 5,726 | $129.28 | $98.98 |
States with the most G0398 services (2024)
| State | Services | Avg. paid |
|---|---|---|
| North Carolina | 1,132 | $38.79 |
| Florida | 868 | $97.86 |
| Texas | 815 | $99.61 |
| California | 621 | $137.39 |
| Ohio | 574 | $200.72 |
NCCI unit limits (MUE)
| Claim type | Max units per day | Rationale |
|---|---|---|
| outpatient hospital claims | 1 | Code Descriptor / CPT Instruction |
| practitioner claims | 1 | Code Descriptor / CPT Instruction |
Medicare policy articles for this code
- A53019: Polysomnography and Sleep Studies – Medical Policy Article (Wellpoint Federal (MAC - Part A, MAC - Part B))
- A56903: Billing and Coding: Polysomnography and Other Sleep Studies (WPS Insurance Corporation (MAC - Part A, MAC - Part B))
- A56923: Billing and Coding: Outpatient Sleep Studies (Novitas Solutions, Inc. (MAC - Part A, MAC - Part B))
- A56995: Billing and Coding: Polysomnography (Palmetto GBA (MAC - Part A, MAC - Part B))
- A57049: Billing and Coding: Polysomnography and Other Sleep Studies (CGS Administrators, LLC (MAC - Part A, MAC - Part B))
- A57496: Billing and Coding: Polysomnography and Sleep Testing (First Coast Service Options, Inc. (MAC - Part A, MAC - Part B))
- A57697: Billing and Coding: Polysomnography and Other Sleep Studies (Noridian Healthcare Solutions, LLC (MAC - Part A, MAC - Part B))
- A58559: Billing and Coding: Independent Diagnostic Testing Facilities (IDTF) (Palmetto GBA (MAC - Part B))
Covered diagnoses (87 ICD-10-CM codes)
The diagnoses most often listed as covered in the policy articles above:
| ICD-10-CM | Diagnosis | Articles listing it |
|---|---|---|
| G47.10 | Hypersomnia, unspecified | 6 |
| G47.11 | Idiopathic hypersomnia with long sleep time | 6 |
| G47.12 | Idiopathic hypersomnia without long sleep time | 6 |
| G47.30 | Sleep apnea, unspecified | 6 |
| G47.31 | Primary central sleep apnea | 6 |
| G47.33 | Obstructive sleep apnea (adult) (pediatric) | 6 |
| G47.34 | Idiopathic sleep related nonobstructive alveolar hypoventilation | 6 |
| G47.35 | Congenital central alveolar hypoventilation syndrome | 6 |
| G47.36 | Sleep related hypoventilation in conditions classified elsewhere | 6 |
| G47.411 | Narcolepsy with cataplexy | 6 |
Showing 10 of 87. The full list, non-covered diagnoses and CSV export are in Caduvo.
What changed for G0398
- 2008-03-13: G0398 added to HCPCS Level II
- Next scheduled CMS quarterly update (HCPCS and DMEPOS fee schedule): 2027-01-01
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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- G0303 — Pre-operative pulmonary surgery services for preparation for lvrs, 10 to 15 days of services
- G0304 — Pre-operative pulmonary surgery services for preparation for lvrs, 1 to 9 days of services
- G0305 — Post-discharge pulmonary surgery services after lvrs, minimum of 6 days of services
- G0306 — Complete cbc, automated (hgb, hct, rbc, wbc, without platelet count) and automated wbc differential count
- G0307 — Complete (cbc), automated (hgb, hct, rbc, wbc; without platelet count)
- G0308 — Creation of subcutaneous pocket with insertion of 180 day implantable interstitial glucose sensor, including system activation and patient training
- G0309 — Removal of implantable interstitial glucose sensor with creation of subcutaneous pocket at different anatomic site and insertion of new 180 day implantable sensor, including system activation
- G0310 — Immunization counseling by a physician or other qualified health care professional when the vaccine(s) is not administered on the same date of service, 5 to 15 mins time (this code is used for medicaid billing purposes)
- G0311 — Immunization counseling by a physician or other qualified health care professional when the vaccine(s) is not administered on the same date of service, 16-30 mins time (this code is used for medicaid billing purposes)
- G0312 — Immunization counseling by a physician or other qualified health care professional when the vaccine(s) is not administered on the same date of service for ages under 21, 5 to 15 mins time (this code is used for medicaid billing purposes)
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Next steps
- Run a reimbursement report for a device billed under G0398
- Watch G0398 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for G0398
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.