NPWT Billing and Coding Guide: CPT Codes, Modifiers, and Documentation

NPWT claims can go wrong even when the treatment itself was done correctly. One of the first places to check is the CPT code for negative pressure wound therapy.

The problem usually comes down to choosing between 97605, 97606, 97607, and 97608. The wound size matters. So does the type of NPWT system used. Add modifiers, documentation, debridement, and payer billing rules to the claim, and a simple wound VAC service can turn into a denial or payment issue.

For wound care practices, knowing the 97605 CPT code, when to use 97606, and how the disposable-device codes 97607 and 97608 differ can prevent avoidable billing problems.

Below, we 

break down the NPWT CPT codes, when each one applies, the wound vac billing guidelines to watch, and the documentation your claim needs to support payment.

What are the CPT codes for Negative Pressure Wound Therapy

There are four main CPT codes used for negative pressure wound therapy: 97605, 97606, 97607, and 97608. The correct code depends mainly on the type of equipment being used and the total surface area of the wound or wounds treated during the session.

CPT Code	Device Type	Wound Size	Code Description
97605	Durable NPWT	50 sq cm or less	NPWT using durable equipment, per session
97606	Durable NPWT	More than 50 sq cm	NPWT using durable equipment, per session
97607	Disposable NPWT	50 sq cm or less	NPWT using disposable equipment, per session
97608	Disposable NPWT	More than 50 sq cm	NPWT using disposable equipment, per session

97605 and 97606 are for durable NPWT systems, while 97607 and 97608 are for disposable systems. Within each group, the 50 sq cm threshold determines which code applies.

Another detail to watch is that these codes are reported per session, not simply once for each wound. When multiple wounds are treated during the same session, follow the applicable payer guidance for determining the wound surface area and selecting the code.

If you need to review other wound care codes, see our wound care coding cheat sheet.

How Do You Choose the Right NPWT CPT Code

Choosing the right NPWT code comes down to two things: the type of equipment used and the total wound surface area treated.

If the service uses durable NPWT equipment, the applicable code is 97605 or 97606. For disposable, non-durable NPWT, the choice is 97607 or 97608.

Then check the wound size:

• 50 sq cm or less: 97605 for durable equipment or 97607 for disposable equipment

• More than 50 sq cm: 97606 for durable equipment or 97608 for disposable equipment

For example, a 35 sq cm wound treated with durable NPWT falls under 97605, while a 65 sq cm wound falls under 97606. The documentation should clearly show the equipment used and measured wound surface area; “large wound” alone is not enough.

What Are the NPWT Billing Guidelines

The NPWT billing guidelines go beyond choosing the CPT code. Before submitting a claim, check the equipment, wound measurement, documentation, and payer requirements.

For 97605 and 97606, the service includes NPWT with the related wound assessment and ongoing-care instructions. 97607 and 97608 apply to disposable, non-durable NPWT systems and include the exudate management collection system.

Medicare separately recognizes NPWT DME items such as E2402, A6550, and A7000 under applicable DME billing rules. These rules should not automatically be applied to every professional NPWT claim or payer.

Also, a dressing change alone does not support reporting 97605–97608. The claim needs documentation supporting the active NPWT service represented by the code.

Can NPWT Be Billed With Debridement

Yes. Debridement (CPT 97597-97598 for selective, or 11042-11047 for surgical) and NPWT (97605-97608) can be billed on the same date of service. Both have to be performed and documented separately.

In practice, debridement typically happens right before the NPWT application. Payers expect separate clinical notes for each service. Don't combine them into one billing line or one clinical narrative.

Which Modifiers Are Used With Negative Pressure Wound Therapy Codes

Modifiers with NPWT are not something to add simply because two services happened on the same date.

• Modifier 59 may apply when a service is genuinely distinct, such as treatment involving a separate anatomical site. The documentation should make that distinction clear. When a more specific modifier, such as an anatomical modifier, is appropriate, CMS recommends using it instead of defaulting to 59.

• Modifier 25 applies to the E/M code when the provider performs a significant, separately identifiable evaluation and management service on the same day as NPWT. A routine wound assessment that is already part of the procedure does not automatically support a separate E/M code.

• Modifier KX is different. For Medicare, it is used on applicable DME NPWT pump and supply claims when the coverage requirements under the applicable Medicare policy have been met. It should not be treated as a modifier that automatically belongs on every professional 97605, 97606, 97607, or 97608 claim.

What Documentation Does NPWT Require

Medicare's LCD L33821 is the rulebook for NPWT coverage, and it's specific about what your documentation needs to include. Miss any of these, and you're opening the door to audits and recoupments.

1. Wound measurements: Length, width, and depth recorded before and after treatment. Payers want to see that the wound is actually improving. If there's no measurable change after four weeks, expect a coverage review.

2. Wound type and location: Be specific. Wound on leg isn't enough. "Stage III pressure ulcer on left lateral malleolus" is what payers expect.

3. Device type: Document whether you're using a durable or disposable system, including brand name and model when possible. This ties directly to which CPT code you bill.

4. Pressure settings: The negative pressure level (typically -75 to -125 mmHg) should be in the note. If you change the pressure, document why.

5. Medical necessity: LCD L33821 requires that NPWT is being used because other wound care methods haven't worked or aren't appropriate. Your notes need to explain why NPWT was chosen over standard wound care.

6. Clinical progress: Week-over-week documentation showing wound improvement. Medicare reviews NPWT claims closely, and "wound is improving" without actual measurements will get flagged.

If your team handles debridement before NPWT, make sure that documentation is tight too. Our wound debridement billing guide covers what you need.

What Are the Common NPWT Billing Errors

These are the mistakes that cost wound care practices the most revenue:

1. Billing supply codes with disposable NPWT codes. HCPCS codes A6550 (dressing) and A7000 (canister) are billed separately with durable systems (97605, 97606). But with disposable systems (97607, 97608), supplies are bundled in. Adding them separately triggers a denial.

2. Missing modifier KX on Medicare claims. No KX = no payment. Every time. And appending it without supporting documentation makes it worse at audit.

3. Wrong wound measurements. A 48 sq cm wound is CPT 97605. A 52 sq cm wound is CPT 97606. Four centimeters is the difference between a clean claim and a denial.

4. No medical necessity statement. "Patient needs NPWT" isn't documentation. Payers want to know what other treatments were tried and why NPWT is the appropriate next step.

If NPWT denials are eating into your collections, schedule a call with our wound care billing team. We handle NPWT coding, modifier compliance, and denial recovery every day.

FAQ

1. Is negative pressure wound therapy the same as wound vac therapy?

Yes. Negative pressure wound therapy (NPWT) is commonly called wound VAC therapy. A wound VAC uses controlled suction to help manage wound drainage and support healing. 

2. What is the CPT code description for 97605?

CPT 97605 is used for negative pressure wound therapy with durable equipment when the total treated wound surface area is 50 sq cm or less, reported per session. 

3. What is the ICD-10 code for negative pressure wound therapy?

There is no single ICD-10 code for NPWT itself. The diagnosis code should identify the underlying wound or condition being treated, based on the patient's documentation.