HCPCS Level II A6531: Below-Knee Gradient Compression Stocking, 30-40 mmHg

HCPCS Level II code A6531 describes a single below-knee gradient compression stocking (30–40 mmHg) used as a surgical dressing; the service is a durable medical supply typically provided in the ambulatory surgical setting or post-operative care to support venous return and manage post-surgical edema, billed per stocking (each).

For related coverage guidance, see recent payer policy updates: Salivary Hormone Testing, Bone Turnover Markers Testing, Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing.

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HCPCS Level II A6531: Below-Knee Gradient Compression Stocking, 30-40 mmHg

For related coverage guidance, see recent payer policy updates: Salivary Hormone Testing, Bone Turnover Markers Testing, Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing.

Customize your policy alerts

Sign up for hcpcs A6531 policy alerts

Get alerted when payer policies referencing A6531 are released or updated.

Monitor payer policy activity

Receive email alerts as soon as relevant payer policies are published or updated.

Clinical & Coding Specifications

Clinical Context

A 62-year-old patient presents to the ambulatory surgical center immediately following varicose vein ligation and ambulatory dermatologic excision of a lower leg lesion. The surgeon applies a sterile, below-knee gradient compression stocking sized to deliver 30–40 mmHg to the operative limb as part of the post-procedure dressing and to reduce postoperative edema and venous stasis. Typical workflow: intraoperative dressing stage where the surgical team verifies limb laterality (LT/RT), sizes and places the stocking over sterile dressings, documents the item as a surgical dressing on the operative report and supply log, and charges the HCPCS Level II code A6531 on the claim with appropriate modifiers reflecting laterality or unusual circumstances. Typical site of service is an ambulatory surgery center or outpatient hospital surgical suite; the stocking is billed as a disposable, single-use item per limb.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`36478`	Endovenous thermal ablation of incompetent vein, 1 vein, unilateral	Commonly performed procedure for varicose veins after which below-knee compression stockings (`A6531`) may be applied as postoperative dressing
`37230`	Transcatheter therapy, embolization, any method, for venous malformations	May precede application of compression stocking to manage venous return and postprocedure swelling
`13100`	Repair, complex, forehead, cheeks, chin, mouth, neck, axillae, genitalia, hands or feet; 1.25 cm to 2.5 cm	Dermatologic excisions on lower leg may be followed by placement of a compression stocking as part of dressing supplies
`29580`	Application of multi-component compression system; leg (including ankle and calf), short stretch bandage, each limb	Alternative or complementary compression therapy; CPT codes like this are part of the same clinical pathway when compression is applied for edema control
`99070`	Supplies and materials (except spectacles), used solely by the patient, billed by the provider	General supply code sometimes used by non-institutional providers when HCPCS supplies are not applicable; relates to documentation of supply cost when `A6531` is also documented

Related Modifiers

5 rows

Modifier	Description	When to Use
59	Modifier 59 indicates a distinct procedural service when two procedures that are not normally billed together are clinically and procedurally separate. The CPT definition (as reiterated by CMS)…	- Use modifier -59 to report a distinct procedural service when documentation supports that the procedure reported is not normally billed together with another service on the same day because of a…
52	Modifier ‑52 (Reduced Services) indicates that a service or procedure was partially reduced or omitted at the provider’s discretion, allowing reporting of the basic procedure number with a qualifier…	- Use modifier -52 when a physician or qualified health professional electively reduces or omits part of a procedure or service (for example, performing fewer required views or omitting a portion of…
53	Modifier 53 (Discontinued Procedure) signals that a surgical or diagnostic service was begun by the physician but terminated because of extenuating circumstances that threatened the patient’s…	- Use modifier -53 when a physician/qualified healthcare professional has started a surgical or diagnostic procedure (e.g., anesthesia administered, incision or scope insertion) and then discontinues…
22	Modifier –22 (Increased Procedural Services) is used when a reported procedure is substantially more extensive than normally required. The CPT Manual and CMS state it may be appended only when the…	- When to use: Append modifier -22 to a procedural CPT code when the service performed is substantially more extensive than the usual service described by that code — i.e., the procedure required…
23	Modifier -23 (Unusual Anesthesia) is used on anesthesia service CPT codes when a procedure that normally requires no anesthesia or only local anesthesia must be performed under general anesthesia…	- Use modifier -23 only on anesthesia CPT codes (00100–01999) when a procedure that normally requires no anesthesia or only local anesthesia must be performed under general anesthesia because of…

Related Provider Taxonomies

8 rows

Taxonomy Code	Specialty	Notes
207Q00000X	Family Medicine Physician	Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadt…
207L00000X	Anesthesiology Physician	An anesthesiologist is trained to provide pain relief and maintenance, or restoration, of a stable condition during and immediately following an opera…
208800000X	Urology Physician	A urologist manages benign and malignant medical and surgical disorders of the genitourinary system and the adrenal gland. This specialist has compreh…
208600000X	Surgery Physician	A general surgeon has expertise related to the diagnosis - preoperative, operative and postoperative management - and management of complications of s…
163W00000X	Registered Nurse	(1) A registered nurse is a person qualified by graduation from an accredited nursing school (depending upon schooling, a registered nurse may receive…
2086S0122X	Plastic and Reconstructive Surgery Physician	A surgeon who specializes in plastic and reconstructive surgery.
101YP1600X	Pastoral Counselor	Behavioral Health & Social Service Providers · Counselor
1041S0200X	School Social Worker	Behavioral Health & Social Service Providers · Social Worker

Related ICD-10-CM Codes

20 rows

ICD-10-CM Code	Description
I74.3	Embolism and thrombosis of arteries of the lower extremities
I74.4	Embolism and thrombosis of arteries of extremities, unspecified
I74.5	Embolism and thrombosis of iliac artery
I80.209	Phlebitis and thrombophlebitis of unspecified deep vessels of unspecified lower extremity
I80.219	Phlebitis and thrombophlebitis of unspecified iliac vein
I83.10	Varicose veins of unspecified lower extremity with inflammation
I83.11	Varicose veins of right lower extremity with inflammation
I83.90	Asymptomatic varicose veins of unspecified lower extremity
I83.91	Asymptomatic varicose veins of right lower extremity
I87.2	Venous insufficiency (chronic) (peripheral)

Showing 1–10 of 20

Related Payer Policy Updates

Specialty: Endocrinology1 / 3

10 rows

Policy	Payer	Effective Date
Salivary Hormone Testing	Oscar Health	2026-10-01
Bone Turnover Markers Testing	Oscar Health	2026-10-01
Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing	Oscar Health	2026-10-01
Testosterone — Coverage Criteria for Measurement and Monitoring	Oscar Health	2026-10-01
Thyroid Disease Testing	Oscar Health	2026-10-01
Diabetes Mellitus Testing — Coverage Criteria	Oscar Health	2026-10-01
Thyroid Disease Testing	blue cross blue shield - louisiana	2026-09-15
Thyroid Disease Testing	Blue Cross Blue Shield - New Mexico	2026-09-04
Parathyroid Hormone, Phosphorous, Calcium and Magnesium Testing	Blue Cross Blue Shield - New Mexico	2026-09-04
Testosterone laboratory testing and management	Premera Bluecross	2026-09-04

Related Codes

HCPCS-A4206-STERILE-SYRINGE-1CC-NEEDLE

HCPCS A4206: Syringe with Needle, 1 cc or Less, Sterile

HCPCS-A4207-STERILE-2CC-SYRINGE-WITH-NEEDLE

HCPCS Level II A4207: Syringe with Needle, Sterile 2 cc

HCPCS-A4208-STERILE-3CC-SYRINGE-WITH-NEEDLE

HCPCS Level II A4208: Syringe with Needle, Sterile 3 cc

HCPCS-A4209-STERILE-SYRINGE-WITH-NEEDLE-5CC-OR-GREATER

HCPCS Level II A4209: Syringe with Needle, Sterile 5 cc or Greater

HCPCS-A4210-NEEDLE-FREE-INJECTION-DEVICE

HCPCS Level II A4210: Needle-free Injection Device, Each

HCPCS-A4211-SUPPLIES-SELF-ADMINISTERED-INJECTIONS

HCPCS Level II A4211: Supplies for Self-Administered Injections

HCPCS-A4212-NON-CORING-NEEDLE-STYLET-CATHETER-ACCESS-SUPPLY

HCPCS Level II A4212: Non-coring Needle or Stylet with/without Catheter

HCPCS-A4213-STERILE-SYRINGE-20CC-OR-GREATER

HCPCS Level II A4213: Syringe, Sterile, 20 cc or Greater, Each

HCPCS-A4215-STERILE-NEEDLE-SINGLE-EACH

HCPCS Level II A4215: Needle, Sterile, Any Size

HCPCS-A4216-STERILE-DILUENT-FLUSH-10ML

HCPCS Level II A4216: Sterile Diluent/Flush, 10 ml

Showing 1–10 of 633

Frequently Asked Questions

References

1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.

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Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

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Clinical & Coding Specifications

Clinical Context

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`36478`	Endovenous thermal ablation of incompetent vein, 1 vein, unilateral	Commonly performed procedure for varicose veins after which below-knee compression stockings (`A6531`) may be applied as postoperative dressing
`37230`	Transcatheter therapy, embolization, any method, for venous malformations	May precede application of compression stocking to manage venous return and postprocedure swelling
`13100`	Repair, complex, forehead, cheeks, chin, mouth, neck, axillae, genitalia, hands or feet; 1.25 cm to 2.5 cm	Dermatologic excisions on lower leg may be followed by placement of a compression stocking as part of dressing supplies
`29580`	Application of multi-component compression system; leg (including ankle and calf), short stretch bandage, each limb	Alternative or complementary compression therapy; CPT codes like this are part of the same clinical pathway when compression is applied for edema control
`99070`	Supplies and materials (except spectacles), used solely by the patient, billed by the provider	General supply code sometimes used by non-institutional providers when HCPCS supplies are not applicable; relates to documentation of supply cost when `A6531` is also documented

Related Modifiers

5 rows

Modifier	Description	When to Use
59	Modifier 59 indicates a distinct procedural service when two procedures that are not normally billed together are clinically and procedurally separate. The CPT definition (as reiterated by CMS)…	- Use modifier -59 to report a distinct procedural service when documentation supports that the procedure reported is not normally billed together with another service on the same day because of a…
52	Modifier ‑52 (Reduced Services) indicates that a service or procedure was partially reduced or omitted at the provider’s discretion, allowing reporting of the basic procedure number with a qualifier…	- Use modifier -52 when a physician or qualified health professional electively reduces or omits part of a procedure or service (for example, performing fewer required views or omitting a portion of…
53	Modifier 53 (Discontinued Procedure) signals that a surgical or diagnostic service was begun by the physician but terminated because of extenuating circumstances that threatened the patient’s…	- Use modifier -53 when a physician/qualified healthcare professional has started a surgical or diagnostic procedure (e.g., anesthesia administered, incision or scope insertion) and then discontinues…
22	Modifier –22 (Increased Procedural Services) is used when a reported procedure is substantially more extensive than normally required. The CPT Manual and CMS state it may be appended only when the…	- When to use: Append modifier -22 to a procedural CPT code when the service performed is substantially more extensive than the usual service described by that code — i.e., the procedure required…
23	Modifier -23 (Unusual Anesthesia) is used on anesthesia service CPT codes when a procedure that normally requires no anesthesia or only local anesthesia must be performed under general anesthesia…	- Use modifier -23 only on anesthesia CPT codes (00100–01999) when a procedure that normally requires no anesthesia or only local anesthesia must be performed under general anesthesia because of…

Related Provider Taxonomies

8 rows

Taxonomy Code	Specialty	Notes
207Q00000X	Family Medicine Physician	Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadt…
207L00000X	Anesthesiology Physician	An anesthesiologist is trained to provide pain relief and maintenance, or restoration, of a stable condition during and immediately following an opera…
208800000X	Urology Physician	A urologist manages benign and malignant medical and surgical disorders of the genitourinary system and the adrenal gland. This specialist has compreh…
208600000X	Surgery Physician	A general surgeon has expertise related to the diagnosis - preoperative, operative and postoperative management - and management of complications of s…
163W00000X	Registered Nurse	(1) A registered nurse is a person qualified by graduation from an accredited nursing school (depending upon schooling, a registered nurse may receive…
2086S0122X	Plastic and Reconstructive Surgery Physician	A surgeon who specializes in plastic and reconstructive surgery.
101YP1600X	Pastoral Counselor	Behavioral Health & Social Service Providers · Counselor
1041S0200X	School Social Worker	Behavioral Health & Social Service Providers · Social Worker

Related ICD-10-CM Codes

20 rows

ICD-10-CM Code	Description
I74.3	Embolism and thrombosis of arteries of the lower extremities
I74.4	Embolism and thrombosis of arteries of extremities, unspecified
I74.5	Embolism and thrombosis of iliac artery
I80.209	Phlebitis and thrombophlebitis of unspecified deep vessels of unspecified lower extremity
I80.219	Phlebitis and thrombophlebitis of unspecified iliac vein
I83.10	Varicose veins of unspecified lower extremity with inflammation
I83.11	Varicose veins of right lower extremity with inflammation
I83.90	Asymptomatic varicose veins of unspecified lower extremity
I83.91	Asymptomatic varicose veins of right lower extremity
I87.2	Venous insufficiency (chronic) (peripheral)

Showing 1–10 of 20

Related Payer Policy Updates

Specialty: Endocrinology1 / 3

10 rows

Policy	Payer	Effective Date
Salivary Hormone Testing	Oscar Health	2026-10-01
Bone Turnover Markers Testing	Oscar Health	2026-10-01
Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing	Oscar Health	2026-10-01
Testosterone — Coverage Criteria for Measurement and Monitoring	Oscar Health	2026-10-01
Thyroid Disease Testing	Oscar Health	2026-10-01
Diabetes Mellitus Testing — Coverage Criteria	Oscar Health	2026-10-01
Thyroid Disease Testing	blue cross blue shield - louisiana	2026-09-15
Thyroid Disease Testing	Blue Cross Blue Shield - New Mexico	2026-09-04
Parathyroid Hormone, Phosphorous, Calcium and Magnesium Testing	Blue Cross Blue Shield - New Mexico	2026-09-04
Testosterone laboratory testing and management	Premera Bluecross	2026-09-04

Related Codes

HCPCS-A4206-STERILE-SYRINGE-1CC-NEEDLE

HCPCS A4206: Syringe with Needle, 1 cc or Less, Sterile

HCPCS-A4207-STERILE-2CC-SYRINGE-WITH-NEEDLE

HCPCS Level II A4207: Syringe with Needle, Sterile 2 cc

HCPCS-A4208-STERILE-3CC-SYRINGE-WITH-NEEDLE

HCPCS Level II A4208: Syringe with Needle, Sterile 3 cc

HCPCS-A4209-STERILE-SYRINGE-WITH-NEEDLE-5CC-OR-GREATER

HCPCS Level II A4209: Syringe with Needle, Sterile 5 cc or Greater

HCPCS-A4210-NEEDLE-FREE-INJECTION-DEVICE

HCPCS Level II A4210: Needle-free Injection Device, Each

HCPCS-A4211-SUPPLIES-SELF-ADMINISTERED-INJECTIONS

HCPCS Level II A4211: Supplies for Self-Administered Injections

HCPCS-A4212-NON-CORING-NEEDLE-STYLET-CATHETER-ACCESS-SUPPLY

HCPCS Level II A4212: Non-coring Needle or Stylet with/without Catheter

HCPCS-A4213-STERILE-SYRINGE-20CC-OR-GREATER

HCPCS Level II A4213: Syringe, Sterile, 20 cc or Greater, Each

HCPCS-A4215-STERILE-NEEDLE-SINGLE-EACH

HCPCS Level II A4215: Needle, Sterile, Any Size

HCPCS-A4216-STERILE-DILUENT-FLUSH-10ML

HCPCS Level II A4216: Sterile Diluent/Flush, 10 ml

Showing 1–10 of 633

Frequently Asked Questions

References

1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.

Published by

Trek Health powers OpenPayer with a leading commercial payer intelligence platform, seamlessly converting fragmented payer data into actionable insights for provider organizations.

HCPCS Level II A6531: Below-Knee Gradient Compression Stocking, 30-40 mmHg

Sign up for hcpcs A6531 policy alerts

HCPCS Level II A6531: Below-Knee Gradient Compression Stocking, 30-40 mmHg

Sign up for hcpcs A6531 policy alerts

Clinical & Coding Specifications

Clinical Context

Related CPT Codes

Related Modifiers

Related Provider Taxonomies

Related ICD-10-CM Codes

Related Payer Policy Updates

Related Codes

What does HCPCS code A6531 represent and how is it documented?

In what clinical scenarios and workflow is A6531 commonly used?

How is A6531 billed and in what sites of service is it typically provided?

Which CPT codes and procedures are commonly associated with use of A6531?

What ICD-10 diagnoses are relevant when A6531 is applied as a surgical dressing?

References

Clinical & Coding Specifications

Clinical Context

Related CPT Codes

Related Modifiers

Related Provider Taxonomies

Related ICD-10-CM Codes

Related Payer Policy Updates

Related Codes

What does HCPCS code A6531 represent and how is it documented?

In what clinical scenarios and workflow is A6531 commonly used?

How is A6531 billed and in what sites of service is it typically provided?

Which CPT codes and procedures are commonly associated with use of A6531?

What ICD-10 diagnoses are relevant when A6531 is applied as a surgical dressing?

References