HCPCS codes for compression garments and stockings: the two coverage doors
Gradient compression stockings, wraps, and lymphedema garments live in the HCPCS A6 codes - and most denials here are benefit errors, not code errors. Medicare pays for compression stockings, wraps, and lymphedema garments through exactly two narrow doors: a surgical-dressing pathway for open venous stasis ulcers, and the lymphedema benefit added in 2024. Here is how to tell which door a claim goes through, and how to bill it once inside.
The compression code landscape
Compression garments live in the HCPCS A6 codes, and the family is bigger than most coders expect: the gradient compression stocking family (the A6530-A6549 block), adjustable-strap wraps, nighttime garments (A6519-A6529), custom-fabricated burn garments (A6501-A6513), and a large block of standard and custom codes - sleeves, gloves, gauntlets, toe caps, and bandaging supplies - added in 2024 for the Medicare lymphedema benefit.
| Code | CMS description |
|---|---|
| A6530 | Gradient compression stocking, below knee, 18-30 mmhg, each |
| A6531 | Gradient compression stocking, below knee, 30-40 mmhg, used as a surgical dressing, each |
| A6552 | Gradient compression stocking, below knee, 30-40 mmhg, each |
| A6583 | Gradient compression wrap with adjustable straps, below knee, each |
| A6524 | Gradient compression garment, lower leg and foot, padded, for nighttime use, each |
| A6578 | Gradient compression arm sleeve, each |
| A6507 | Compression burn garment, foot to knee length, custom fabricated |
Look at A6531 and A6552: the same below-knee 30-40 mmHg stocking, two different codes. The phrase “used as a surgical dressing” in the descriptor is not flavor text - it names the benefit pathway the code travels through, and matching the code to the pathway is most of the work in this family. Use the lookup tool to see every variant before you bill.
The Medicare trap: no open ulcer, no stocking benefit
Compression stockings are not durable medical equipment - they are not durable - and Medicare has no general benefit for them. For a patient with varicose veins or chronic venous insufficiency and no open wound, a compression stocking claim denies as noncovered no matter which code it carries or how thorough the documentation is.
A6531, A6532, and A6545 - and only while an open venous stasis ulcer is being treated. Venous insufficiency without an ulcer, ulcer prevention, and ulcers that have healed are all noncovered under this pathway.
Each covered line must carry the AW modifier - “item furnished in conjunction with a surgical dressing” - plus RT or LT for the leg treated. Note what is missing from the covered trio: a light-compression option. A6530 (18-30 mmHg) has no surgical-dressing counterpart, so it is never payable as a dressing. The non-elastic wrap A6545 is also quantity-limited under DME MAC policy - one per leg every six months.
A6531-AW-RT x 1 A6531-AW-LT x 1Why: the open ulcers qualify the stockings as surgical dressings, so A6531 - not A6552 - applies, with AW on each line. The same code on both legs bills as two lines of one unit with RT and LT, not one line of two units. The pair is still two units total, because the descriptor says “each.” Without an open ulcer, the same stockings are noncovered however they are coded.
The lymphedema benefit: what changed on January 1, 2024
The Lymphedema Treatment Act created a new Medicare Part B benefit category, effective January 1, 2024, for compression treatment items: standard and custom gradient compression garments (daytime and nighttime), adjustable-strap wraps, compression bandaging supplies, and accessories. The catch is in the name: claims must carry a qualifying lymphedema diagnosis (for example I89.0) - garments billed for any other condition deny as noncovered. The items are billed to the DME MAC like other DMEPOS.
| Item type | Medicare allowance |
|---|---|
| Daytime garments or wraps | Three per affected body area, once every six months |
| Nighttime garments | Two per affected body area, once every two years |
Replacements outside those windows are payable only for loss, theft, irreparable damage, or a documented change in the patient's condition that requires a different size or type. Custom-fabricated codes sit alongside the standard ones (A6553 is the custom twin of A6552) and need documentation of why a standard garment cannot work - anatomy outside standard sizing, skin folds that need a special knit, or fabric intolerance.
Units, laterality, and the mmHg tiers
Nearly every descriptor in this family ends in “each” - per stocking, per sleeve, per glove. A pair is two units, and bilateral same-code items go on two lines with RT and LT, one unit per line; DME MACs reject a single combined-RTLT line. (More on the laterality set in the modifiers guide.)
The compression level is part of the code. For a below-knee stocking:
| Compression level | Standard code | Surgical-dressing code |
|---|---|---|
| 18-30 mmHg | A6530 | none - not covered as a dressing |
| 30-40 mmHg | A6552 | A6531 |
| 40 mmHg and up | A6554 | A6532 (40-50 mmHg) |
Length changes the code too - thigh-length stockings have their own tier set (A6533, A6534, A6535), as do full-length and waist-length styles. Bill the garment actually supplied, and make sure the mmHg on the claim matches the mmHg on the order.
The commercial-payer angle: the compression trial
Commercial coverage of the garments themselves varies widely, but compression plays a second, higher-stakes role: many commercial policies require a documented trial of conservative therapy - gradient compression stockings plus measures like elevation and exercise - before they will authorize vein procedures such as endovenous thermal ablation or sclerotherapy. The required duration and compression level vary by payer, so check the specific policy.
That makes today's stocking documentation tomorrow's procedure authorization. Record the prescribed compression level in mmHg, the start date, the wear schedule, and the symptoms that persisted despite compliant use - the vein-procedure claim will lean on all of it. The full documentation picture is in our vein-ablation medical-necessity guide.
Common mistakes
- Billing stockings for varicose veins with no open ulcer. Medicare has no benefit for them - screen the coverage pathway before picking a code.
- Using A6552 (or A6530) on a wound claim.
A6531,A6532, andA6545are the only stocking and wrap surgical-dressing codes, and each line needsAW. - One line, two units for a pair. Bilateral same-code items bill as two lines, RT and LT, one unit each.
- Custom codes without custom justification. The record must say why a standard garment cannot work, not just that a custom one was ordered.
- Blowing through the frequency windows. Three daytime garments per body area per six months, two nighttime per two years - excess quantities deny unless loss, theft, damage, or a change in condition is documented.
Documentation checklist
- Order for the garment with body area, length, and compression level in mmHg
- Surgical-dressing pathway: the open venous stasis ulcer documented, with a current wound evaluation
- Lymphedema benefit: the qualifying diagnosis, plus the standard-garment rule-out for custom items
- AW plus RT/LT on surgical-dressing lines; one unit per side per line
- Quantity within the frequency limits, or the loss / damage / change-in-condition note
Frequently asked questions
Not without an open wound. Gradient compression stockings are not a Medicare benefit for varicose veins or chronic venous insufficiency alone - those claims deny as noncovered. Coverage opens only when there is an open venous stasis ulcer being treated (the surgical-dressing pathway, where the payable stocking and wrap codes are A6531, A6532, and A6545) or a qualifying lymphedema diagnosis (the benefit that began January 1, 2024).
Three: A6531 (below-knee stocking, 30-40 mmHg), A6532 (below-knee stocking, 40-50 mmHg), and A6545 (non-elastic below-knee wrap, 30-50 mmHg). Each descriptor literally says “used as a surgical dressing.” They are covered only while an open venous stasis ulcer is being treated, and each line needs the AW modifier plus RT or LT. (Custom-fabricated compression burn garments have their own surgical-dressings coverage after burn injuries - a separate pathway from the ulcer rules here.)
Since January 1, 2024, Medicare Part B covers compression treatment items for beneficiaries with a lymphedema diagnosis: standard and custom gradient compression garments (daytime and nighttime), adjustable-strap wraps, bandaging supplies, and accessories. The allowance is three daytime garments per affected body area every six months and two nighttime garments every two years; replacements outside those windows require loss, theft, irreparable damage, or a documented change in condition.
Two - the descriptors say “each,” meaning per stocking, not per pair. For the same code on both legs on the same date, bill two lines of one unit with RT and LT rather than one combined line of two units - DME MACs reject single-line RTLT billing on these codes.
Many commercial policies require a documented trial of conservative therapy - gradient compression plus measures like elevation and exercise - before they will authorize procedures such as endovenous thermal ablation or sclerotherapy. The required duration and compression level vary by payer, so check the specific policy. The stocking itself may be a small claim; the trial documentation is what gets the later procedure approved.