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HCPCS Q4021 · Level II · Q code

Q4021: Cast supplies, short arm splint, adult (11 years +), plaster, HCPCS Level II Q code

Compiled from CMS files by the QuickIntell RCM Editorial Team · Data effective · Method: reference methodology · Report a data correction

Data currency: HCPCS Level II file: October 2026 (effective October 1, 2026); PFS relative value file: RVU26D, released August 26, 2026 (effective October 1, 2026); DMEPOS fee schedule: DME26-D (October 2026) (effective October 1, 2026); NCCI MUE tables: 2026 Q4 (effective October 1, 2026); NCCI PTP edits: v323r0 (2026 Q4) (effective October 1, 2026); OPPS Addendum B: October 2026 (effective October 1, 2026). Next CMS release: January 1, 2027 (quarterly update) for the HCPCS Level II file and DMEPOS fee schedule and NCCI MUE tables and NCCI PTP edits and OPPS Addendum B; RVU27A with the CY2027 PFS final rule, effective January 1, 2027 for the PFS relative value file.

Key facts for Q4021

Medicare payment
$8.59
DMEPOS non-rural state fees
Coverage code
C
carrier judgment, so the Medicare contractor decides coverage
DME supplier MUE
0
MAI 3
OPPS status
SI B
Non-allowed item or service for OPPS
NCCI PTP pairs
0
practitioner file
LCDs and articles
0 / 0

TL;DR

Q4021 is a Level II code from the Q section (temporary codes), in use since 2001: "Cast supplies, short arm splint, adult (11 years +), plaster". The October 2026 DMEPOS fee schedule (category SC, splints and casts) sets Q4021 at $8.59 in every contiguous state (floor $7.30, ceiling $8.59). CMS caps Q4021 at practitioner 2 (MAI 3, Clinical: Data); hospital outpatient 2 (MAI 3, Clinical: Data); DME supplier 0 (MAI 3, CMS Policy) units per day in the 2026 Q4 MUE tables. No current LCD or billing article lists Q4021; its HCPCS coverage code is C (carrier judgment, so the Medicare contractor decides coverage). OPPS status indicator B: Non-allowed item or service for OPPS. HCPCS record: BETOS D1A (medical/surgical supplies); pricing indicator 55; type of service S (surgical dressings or other medical supplies). 47 other active codes open with "Cast supplies"; related codes: Q4022, Q4012, Q4010, Q4006.

Q4021 descriptor and code status

The October 2026 HCPCS Level II file describes Q4021 as “Cast supplies, short arm splint, adult (11 years +), plaster”. It sits in the Q section (temporary codes), listed with the other Q codes for services and supplies (non-drug).

HCPCS file attributes of Q4021
FieldValue
Short descriptorCast sup sht arm splint plst
Added to HCPCS2001-07-01
Last actionN (no maintenance), effective 2014-10-01
Coverage codeC: carrier judgment, so the Medicare contractor decides coverage
Pricing indicator55: splints and casts
BETOS categoryD1A: medical/surgical supplies
Type of serviceS: surgical dressings or other medical supplies

Medicare payment for Q4021

The October 2026 DMEPOS fee schedule (category SC, splints and casts) sets Q4021 at $8.59 in every contiguous state (floor $7.30, ceiling $8.59). 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 X: statutory exclusion: not a physician service under the fee schedule. Global period XXX (global surgery concept does not apply); PC/TC indicator 9 (professional/technical concept does not apply).

DMEPOS fee schedule (DME26-D)

Jurisdiction L (local Part B MAC), payment category SC (splints and casts). Fees are set per state; AK, HI, PR and VI are not subject to the national ceiling and floor and are listed separately. A rural fee applies only in ZIP codes on the CMS rural ZIP list.

DMEPOS fees for Q4021 by modifier
ModifierFloor / ceilingNon-rural state rangeRural rangeAK / HI / PR / VI
none$7.30 / $8.59$8.59 (49 states)—AK $8.59, HI $8.59, PR $8.59, VI $8.59

Hospital outpatient (OPPS Addendum B)

Status indicator B (Non-allowed item or service for OPPS), with no separate OPPS payment rate.

Medically Unlikely Edits for Q4021

CMS caps Q4021 at practitioner 2 (MAI 3, Clinical: Data); hospital outpatient 2 (MAI 3, Clinical: Data); DME supplier 0 (MAI 3, CMS Policy) units per day in the 2026 Q4 MUE tables. The DME supplier MUE is a date-of-service clinical edit: units above the limit deny but can be paid on appeal with documentation.

MUE values for Q4021 by setting
SettingMUE (units/DOS)MAICMS rationale
Practitioner services23 Date of Service Edit: ClinicalClinical: Data
Facility outpatient hospital23 Date of Service Edit: ClinicalClinical: Data
DME supplier03 Date of Service Edit: ClinicalCMS Policy

The MUE lookup for Q4021 shows every setting next to any other code on the same claim.

NCCI edits and add-on rules

No active practitioner PTP pair lists Q4021 in v323r0.

Q4021 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 Q4021 against a second code to see whether the pair bundles and whether a modifier can separate the services.

Medicare coverage policies for Q4021

No current LCD or billing and coding article lists Q4021. The HCPCS coverage code C means carrier judgment, so the Medicare contractor decides coverage, and any National Coverage Determination for the service still applies.

Denials to expect on Q4021

CARC 50 · N115

the service is not reasonable and necessary for the diagnosis on the claim

CARC 151 · N362

units of Q4021 exceed the DME supplier MUE of 0 per date of service

CARC 4

the modifier reported is inconsistent with the code

CARC 16

the claim lacks information needed to adjudicate the line, such as an order, NPI or required modifier

Where QuickIntell fits for Q4021 claims

QuickAuth coordinates the requirement checks and documentation that DME claims for Q4021 depend on, with human review of each case, and QuickRCM carries claim readiness and the CARC 50, 151 and modifier denials these items draw.

See QuickAuth for requirement checksSee QuickRCM for denial follow-upBook a meeting

Frequently asked questions: HCPCS Q4021

What does HCPCS code Q4021 describe?

"Cast supplies, short arm splint, adult (11 years +), plaster" (short descriptor "Cast sup sht arm splint plst"), in the Q section (temporary codes). Added 2001-07-01; last action N (no maintenance) effective 2014-10-01.

Is Q4021 a CPT code?

It is not. Q4021 belongs to the Q section (temporary codes) of HCPCS Level II, the CMS code set, not to AMA CPT.

What does Medicare pay for Q4021?

The October 2026 DMEPOS fee schedule (category SC, splints and casts) sets Q4021 at $8.59 in every contiguous state (floor $7.30, ceiling $8.59).

How many units of Q4021 can be billed per day?

CMS caps Q4021 at practitioner 2 (MAI 3, Clinical: Data); hospital outpatient 2 (MAI 3, Clinical: Data); DME supplier 0 (MAI 3, CMS Policy) units per day in the 2026 Q4 MUE tables. For the DME supplier MUE (MAI 3), units above 0 deny for the day but can be paid on appeal with documentation; denials arrive as CARC 151.

Does Medicare cover Q4021?

No current LCD or billing article lists Q4021; its HCPCS coverage code is C (carrier judgment, so the Medicare contractor decides coverage).

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.

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.