Key facts for G0400
- Medicare payment
- $220.60
- OPPS rate, SI S
- Coverage code
- C
- carrier judgment, so the Medicare contractor decides coverage
- Facility outpatient MUE
- 1
- MAI 2
- NCCI PTP pairs
- 103
- 100 hospital outpatient
- LCDs and articles
- 7 / 8
TL;DR
G0400 is a Level II code from the G section (procedures and professional services, temporary), in use since 2008: "Home sleep test (hst) with type iv portable monitor, unattended; minimum of 3 channels". Hospital outpatient departments are paid $220.60 for G0400 under status indicator S, APC 5722 (Level 2 Diagnostic Tests and Related Services), minimum unadjusted copayment $44.12 (October 2026 Addendum B). CMS caps G0400 at practitioner 1 (MAI 2, Nature of Service/Procedure); hospital outpatient 1 (MAI 2, Nature of Service/Procedure) units per day in the 2026 Q4 MUE tables. In the NCCI PTP files v323r0 G0400 appears in 12 practitioner pairs as column 2 and 91 as column 1 (most often with 95782, 95783, 95800), and in 12 hospital outpatient pairs as column 2 and 88 as column 1. 7 active LCDs and 8 billing and coding articles list G0400 across 29 states plus DC and 2 territories: L33405 (Polysomnography and Sleep Testing), L35050 (Outpatient Sleep Studies), A53019, A56903. HCPCS record: BETOS T2D (other tests - other); pricing indicator 13; type of service 5 (diagnostic laboratory). 1 other active code opens with "Home sleep test"; related codes: G0399, G0398, G0402, G0397.
G0400 descriptor and code status
The October 2026 HCPCS Level II file describes G0400 as “Home sleep test (hst) with type iv portable monitor, unattended; minimum of 3 channels”. It sits in the G section (procedures and professional services, temporary), listed with the other G codes. Although searches often call it the "G0400 CPT code", G0400 is a HCPCS Level II code maintained by CMS, not an AMA CPT code; both go in the same procedure-code field on the claim.
| Field | Value |
|---|---|
| Short descriptor | Home sleep test/type 4 porta |
| Added to HCPCS | 2008-03-13 |
| Last action | N (no maintenance), effective 2008-03-13 |
| Coverage code | C: carrier judgment, so the Medicare contractor decides coverage |
| Pricing indicator | 13: physician fee schedule, priced by the contractor |
| BETOS category | T2D: other tests - other |
| Type of service | 5: diagnostic laboratory |
Medicare payment for G0400
Hospital outpatient departments are paid $220.60 for G0400 under status indicator S, APC 5722 (Level 2 Diagnostic Tests and Related Services), minimum unadjusted copayment $44.12 (October 2026 Addendum B). The amounts below are national figures from the October 2026 CMS files; the contractor applies the locality, rural or state adjustment and the beneficiary's cost sharing.
Physician fee schedule (RVU26D)
Status C: contractor-priced: the MAC sets RVUs and payment case by case. Global period XXX (global surgery concept does not apply); PC/TC indicator 1 (diagnostic test with professional (26) and technical (TC) components).
G0400 also carries 26 and TC rows in the RVU file, priced separately from the global service.
| Modifier | Status | Non-facility | Facility |
|---|---|---|---|
| 26 | C | n/a | n/a |
| TC | C | n/a | n/a |
Hospital outpatient (OPPS Addendum B)
Status indicator S (Procedure or service, not discounted when multiple), APC 5722 (Level 2 Diagnostic Tests and Related Services), national unadjusted payment $220.60 with a minimum unadjusted copayment of $44.12.
Medically Unlikely Edits for G0400
CMS caps G0400 at practitioner 1 (MAI 2, Nature of Service/Procedure); hospital outpatient 1 (MAI 2, Nature of Service/Procedure) units per day in the 2026 Q4 MUE tables. The facility outpatient MUE is a date-of-service policy edit: units above the limit deny even when split across lines, and appeals rarely succeed.
| Setting | MUE (units/DOS) | MAI | CMS rationale |
|---|---|---|---|
| Practitioner services | 1 | 2 Date of Service Edit: Policy | Nature of Service/Procedure |
| Facility outpatient hospital | 1 | 2 Date of Service Edit: Policy | Nature of Service/Procedure |
The MUE lookup for G0400 shows every setting next to any other code on the same claim.
NCCI edits and add-on rules
In the practitioner PTP file v323r0, G0400 is the column-2 (bundled) code in 12 active pairs, 0% of which allow a modifier and the column-1 code in 91 (55% modifier-allowed); 22 earlier pairs have been deleted. CMS's most frequent rationale for the bundled pairs: Mutually exclusive procedures.
| Column-1 code | Pairs |
|---|---|
| 95782 (CPT; descriptor licensed by AMA) | 1 |
| 95783 (CPT; descriptor licensed by AMA) | 1 |
| 95800 (CPT; descriptor licensed by AMA) | 1 |
| 95801 (CPT; descriptor licensed by AMA) | 1 |
| 95805 (CPT; descriptor licensed by AMA) | 1 |
| 95806 (CPT; descriptor licensed by AMA) | 1 |
| 95807 (CPT; descriptor licensed by AMA) | 1 |
| 95808 (CPT; descriptor licensed by AMA) | 1 |
| Column-2 code | Pairs |
|---|---|
| 0733T (CPT; descriptor licensed by AMA) | 1 |
| 0903T (CPT; descriptor licensed by AMA) | 1 |
| 0904T (CPT; descriptor licensed by AMA) | 1 |
| 0905T (CPT; descriptor licensed by AMA) | 1 |
| 0937T (CPT; descriptor licensed by AMA) | 1 |
| 0938T (CPT; descriptor licensed by AMA) | 1 |
| 0939T (CPT; descriptor licensed by AMA) | 1 |
| 0940T (CPT; descriptor licensed by AMA) | 1 |
In the hospital outpatient PTP file v323r0, G0400 is the column-2 (bundled) code in 12 active pairs, 0% of which allow a modifier and the column-1 code in 88 (95% modifier-allowed); 22 earlier pairs have been deleted. CMS's most frequent rationale for the bundled pairs: Mutually exclusive procedures.
| Column-1 code | Pairs |
|---|---|
| 95782 (CPT; descriptor licensed by AMA) | 1 |
| 95783 (CPT; descriptor licensed by AMA) | 1 |
| 95800 (CPT; descriptor licensed by AMA) | 1 |
| 95801 (CPT; descriptor licensed by AMA) | 1 |
| 95805 (CPT; descriptor licensed by AMA) | 1 |
| 95806 (CPT; descriptor licensed by AMA) | 1 |
| 95807 (CPT; descriptor licensed by AMA) | 1 |
| 95808 (CPT; descriptor licensed by AMA) | 1 |
| Column-2 code | Pairs |
|---|---|
| 0733T (CPT; descriptor licensed by AMA) | 1 |
| 0903T (CPT; descriptor licensed by AMA) | 1 |
| 0904T (CPT; descriptor licensed by AMA) | 1 |
| 0905T (CPT; descriptor licensed by AMA) | 1 |
| 0937T (CPT; descriptor licensed by AMA) | 1 |
| 0938T (CPT; descriptor licensed by AMA) | 1 |
| 0939T (CPT; descriptor licensed by AMA) | 1 |
| 0940T (CPT; descriptor licensed by AMA) | 1 |
G0400 is neither an add-on code nor a designated primary code in the 2026 Q4 NCCI add-on edit file.
Pair counts show exposure, not the answer for one claim. Check G0400 against a second code to see whether the pair bundles and whether a modifier can separate the services.
Medicare coverage policies for G0400
7 active Local Coverage Determinations and 8 billing and coding articles list G0400. Each applies only in its contractor's jurisdiction, and the article carries the diagnosis codes that support the item or service.
- Polysomnography and Sleep Testing (L33405) · First Coast Service Options, Inc.
- LCD L35050: Outpatient Sleep Studies · Novitas Solutions, Inc.
- Polysomnography, LCD L36593 · Palmetto GBA
- Polysomnography and Other Sleep Studies (L36839) · Wisconsin Physicians Service Insurance Corporation
- LCD L38528: Hypoglossal Nerve Stimulation for the Treatment of Obstructive Sleep Apnea · Wisconsin Physicians Service Insurance Corporation
- L36861 Polysomnography and Other Sleep Studies · Noridian Healthcare Solutions, LLC
- L36902 Polysomnography and Other Sleep Studies · CGS Administrators, LLC
| Article | Title | Contractor(s) | Related LCD |
|---|---|---|---|
| A53019 | Polysomnography and Sleep Studies – Medical Policy Article | Wellpoint Federal | — |
| A56903 | Billing and Coding: Polysomnography and Other Sleep Studies | Wisconsin Physicians Service Insurance Corporation | L36839 |
| A56923 | Billing and Coding: Outpatient Sleep Studies | Novitas Solutions, Inc. | L35050 |
| A56995 | Billing and Coding: Polysomnography | Palmetto GBA | L36593 |
| A57049 | Billing and Coding: Polysomnography and Other Sleep Studies | CGS Administrators, LLC | L36901, L36902 |
| A57496 | Billing and Coding: Polysomnography and Sleep Testing | First Coast Service Options, Inc. | L33405, L36222 |
| A57697 | Billing and Coding: Polysomnography and Other Sleep Studies | Noridian Healthcare Solutions, LLC | L36861 |
| A58559 | Billing and Coding: Independent Diagnostic Testing Facilities (IDTF) | Palmetto GBA | — |
Denials to expect on G0400
the diagnosis or documentation does not meet the LCD or billing article that lists G0400
the 26 or TC modifier does not fit the component billed
the claim lacks the description, invoice or pricing detail a contractor-priced code needs
Where QuickIntell fits for G0400 claims
QuickCode supports qualified coder review of units, modifiers and NCCI pairs for G0400 before the claim leaves, and QuickRCM carries claim readiness and the denial follow-up when an edit or coverage policy is missed.
Frequently asked questions: HCPCS G0400
What does HCPCS code G0400 describe?
"Home sleep test (hst) with type iv portable monitor, unattended; minimum of 3 channels" (short descriptor "Home sleep test/type 4 porta"), in the G section (procedures and professional services, temporary). Added 2008-03-13.
Is G0400 a CPT code?
It is not. G0400 belongs to the G section (procedures and professional services, temporary) of HCPCS Level II, the CMS code set, not to AMA CPT. "G0400 CPT code" searches refer to it.
What does Medicare pay for G0400?
Hospital outpatient departments are paid $220.60 for G0400 under status indicator S, APC 5722 (Level 2 Diagnostic Tests and Related Services), minimum unadjusted copayment $44.12 (October 2026 Addendum B).
How many units of G0400 can be billed per day?
CMS caps G0400 at practitioner 1 (MAI 2, Nature of Service/Procedure); hospital outpatient 1 (MAI 2, Nature of Service/Procedure) units per day in the 2026 Q4 MUE tables. For the facility outpatient MUE (MAI 2), units above 1 deny for the whole day as a policy limit; denials arrive as CARC 151.
Does Medicare cover G0400?
Coverage code C (carrier judgment, so the Medicare contractor decides coverage). 7 active LCDs and 8 billing and coding articles list G0400 across 29 states plus DC and 2 territories: L33405 (Polysomnography and Sleep Testing), L35050 (Outpatient Sleep Studies), A53019, A56903.
Sources
Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-10. Verify against the primary file before billing or contracting decisions. The reference methodology explains how each figure is computed from these files.
- HCPCS Level II alpha-numeric file, October 2026Version October 2026 · effective 2026-10-01 · file HCPC2026_OCT_ANWEB_09232026.txtSHA-256 c25240c63108756d…
- Medicare PFS national relative value file RVU26D (non-QPP), October 2026Version RVU26D, released 2026-08-26 · effective 2026-10-01 · file PPRRVU2026_Oct_nonQPP.csvSHA-256 4d0d3f19bd954ffc…
- Medicare PFS national relative value file RVU26D (qualifying APM participants), October 2026Version RVU26D, released 2026-08-26 · effective 2026-10-01 · file PPRRVU2026_Oct_QPP.csvSHA-256 59d3734704853936…
- OPPS Addendum B, October 2026Version October 2026 · effective 2026-10-01 · file 508-compliant-version-2026_October_Web_Addendum_B.09.28.26.csvSHA-256 6ad7393a318bf1b9…
- Integrated Outpatient Code Editor v27.3 data tables: status and payment indicatorsVersion I/OCE v27.3 (October 2026) · effective 2026-10-01 · file Data_Status_Indicator.txtSHA-256 78f119ef0a435351…
- NCCI MUE table, practitioner services, effective 2026-10-01Version 2026 Q4 · effective 2026-10-01 · file MCR_MUE_PractitionerServices_Eff_10-01-2026.csvSHA-256 ef038efaf902b7bd…
- NCCI MUE table, facility services, effective 2026-10-01Version 2026 Q4 · effective 2026-10-01 · file MCR_MUE_OutpatientHospitalServices_Eff_10-01-2026.csvSHA-256 3af9f4e99cc587e2…
- NCCI MUE table, dme services, effective 2026-10-01Version 2026 Q4 · effective 2026-10-01 · file MCR_MUE_DMESupplierServices_Eff_10-01-2026.csvSHA-256 6fa4fbba852f7b74…
- NCCI PTP edits, practitioner, v323r0 (four files)Version v323r0 (2026 Q4) · effective 2026-10-01 · file ccipra-v323r0-f1.TXTSHA-256 7793c0b6686c1e22…
- NCCI PTP edits, hospital outpatient, v323r0 (four files)Version v323r0 (2026 Q4) · effective 2026-10-01 · file ccioph-v323r0-f1.txtSHA-256 063f41b91ef9faa2…
- Medicare Coverage Database, current Billing and Coding Articles exportVersion MCD release 2026-10-08 · effective 2026-10-04 · file article.csvSHA-256 5e95c4a8ac3664be…
- Medicare Coverage Database, current LCD exportVersion MCD release 2026-10-08 · effective 2026-10-04 · file lcd.csvSHA-256 9aee1bd7f14056b0…
Disclaimer
This page is an operational reference compiled from CMS publications: the HCPCS Level II file, the physician, DMEPOS and clinical laboratory fee schedules, OPPS and ASC addenda, NCCI MUE, PTP and add-on edit tables and the Medicare Coverage Database. Amounts are Medicare national figures before locality and state adjustment; Medicaid and commercial payers set their own. CPT codes are shown as numbers only; CPT descriptors are copyright AMA. Nothing here is legal, clinical or billing advice.
Found a figure that does not match the CMS file? Report a data correction with the CMS file and the value you expected; the request reaches the editorial team through the contact form.