CPT code 28003: Incision and drainage below fascia, with or without tendon sheath involvement

CPT code 28003 is the billing code for incision and drainage below the fascia of the foot in multiple areas. It applies with or without tendon sheath involvement. Coders often confuse it with 28002, the single bursal space code, or with the superficial I&D codes 10060 and 10061. That mix-up is a common cause of denials on these claims.

Payers want an operative note that confirms below-fascia access and names each drained area. Without both, 28003 downcodes to 28002 or is rejected outright.

Podiatrists and foot-and-ankle surgeons bill this code for deep-space foot infections, such as plantar space abscesses and web-space infections with subfascial spread. It carries a 90-day global period, and Medicare reimbursement varies by place of service. This reference covers each billing decision so your claims go through clean the first time.

Key takeaways

CPT code 28003 covers I&D below the fascia of the foot in multiple areas, with or without tendon sheath involvement.

Its single-area counterpart is 28002, while 28001 is I&D of a bursa and 10060 and 10061 cover superficial abscesses.

Documentation must confirm below-fascia access and name each area drained, or the claim is likely to downcode or deny.

The code carries a 90-day global period, so an unrelated E&M visit in that window needs modifier 24.

Pabau’s claims management software sends 28003 claims through Claim.MD and tracks each one to payment.

CPT code 28003: Official descriptor and clinical scope

According to the American Medical Association’s CPT code set is the source for the official descriptor. For CPT code 28003, it reads Incision and drainage, below fascia, with or without tendon sheath involvement, foot; multiple areas.

The code sits within the CPT 28000-28035 incision range for foot and toe procedures. It applies when a surgeon opens multiple deep compartments of the foot to drain infection. That infection has tracked below the plantar fascia or into tendon sheaths. A deep drainage confined to a single bursal space maps to 28002 instead.

Typical clinical scenarios that warrant CPT code 28003 include:

• Plantar space abscess with extension into the medial or lateral compartment
• Web-space infection with subfascial spread requiring decompression of two or more web spaces
• Deep foot abscess with concurrent tendon sheath involvement in multiple areas
• Necrotizing soft-tissue infection of the foot requiring multi-compartment decompression

CPT 28003 vs. related incision and drainage codes

Selecting the correct incision and drainage CPT code turns on two questions. How deep is the infection, and how many areas were addressed? The table below maps CPT 28003 against its most commonly confused neighbors.

Neither 10060 nor 10061 fits a below-fascia foot infection. Billing 10060 for a plantar space abscess that required fascial penetration is undercoding, and billing 28003 for a superficial toe abscess is upcoding. The operative note settles it, and the choice always runs in the order shown below.

ICD-10 diagnosis codes commonly paired with CPT code 28003

Every claim for CPT code 28003 needs a supporting ICD-10 diagnosis code that establishes medical necessity. Payers cross-check the diagnosis against the procedure, so the diagnosis has to explain why deep, multi-area drainage was needed.

Laterality matters. Use L03.115 (right lower limb) or L03.116 (left lower limb) whenever the operative note documents the side, and pick L02.611 or L02.612 the same way. Unspecified laterality codes are a low-level audit flag for certain payers. Our reference pages for M72.6 and E11.621 cover those two diagnoses in more depth.

Modifiers for CPT code 28003

CPT code 28003 has a defined set of applicable modifiers. Getting them right prevents unnecessary multiple-procedure reductions and makes sure bilateral cases pay correctly.

Bilateral billing (modifier 50) is uncommon for 28003 because simultaneous bilateral deep foot infections are rare. It does occur in diabetic patients with symmetric complications. Verify the payer’s bilateral billing preference before submitting. Medicare accepts modifier 50 on a single claim line, but many commercial payers require two separate lines with LT and RT.

Medicare reimbursement rates for CPT code 28003

Medicare reimburses CPT code 28003 under the Physician Fee Schedule at different rates depending on the place of service. Non-facility rates apply when the procedure is performed in a physician’s office. Facility rates apply in hospital outpatient departments and ambulatory surgery centers, where the facility bills separately for overhead costs.

Always look up the current-year rate using the CMS Physician Fee Schedule lookup tool. Rates shift each January with the annual conversion factor adjustment. The table below shows how the rate types differ, so confirm the exact 2026 amounts via CMS before billing.

For the exact RVU values and 2026 dollar conversion, use the FastRVU 2026 RVU lookup tool. It mirrors the current CMS dataset and shows work, practice expense, and malpractice RVUs for 28003 at a national level.

Medicaid rates are set by each state and can differ substantially from Medicare. Check the applicable state fee schedule before estimating reimbursement for Medicaid patients.

Global surgical period and bundling rules

CPT code 28003 carries a 90-day global surgical period under the Medicare Physician Fee Schedule. The global package starts the day before surgery and runs 90 days after it. Routine care related to the procedure in that window is bundled into the surgical payment and cannot be billed separately.

Services that are bundled and cannot be billed during the 90-day global window:

• The E&M visit on the day before or the day of surgery, unless it resulted in the decision to operate (modifier 57)
• Routine wound checks and dressing changes at the operative site
• E&M visits for symptoms directly related to the 28003 procedure
• Local anesthesia administration in conjunction with 28003

Services that CAN be billed separately during the global period:

• E&M for a completely unrelated medical problem (append modifier 24)
• Supply codes for wound care materials (verify payer policy, since some bundle them and some allow separate billing)
• Return to the OR for a complication requiring a new procedure (modifier 78)
• Staged or related procedure if clinically distinct from the original drainage (modifier 58)
• An unrelated procedure by the same physician during the global period (modifier 79)

Prior authorization requirements

Medicare does not routinely require prior authorization for CPT code 28003. Most commercial payers follow suit for acute infections requiring urgent surgical drainage. Their requirements vary by plan and change over time, so verify with the payer before a scheduled, non-emergent procedure.

Situations where prior authorization is most likely required:

• Elective or semi-elective cases where the infection is being managed with antibiotics first and drainage is planned in advance
• Managed Medicaid plans with blanket surgical authorization requirements
• Workers’ compensation cases, which typically require authorization regardless of urgency

For emergent presentations where same-day or next-day drainage is clinically necessary, most payers accept post-service authorization within 24 to 48 hours. Document the clinical urgency explicitly in the chart, such as fever, rapid tissue spread, signs of necrotizing infection, or neurovascular compromise. That record protects against retrospective authorization denials.

Documentation requirements for CPT code 28003

The operative note for CPT code 28003 must establish three facts that distinguish it from 28002, 10060, and 10061. Miss any one of them and the claim is vulnerable to a downcode or denial.

• Below-fascia access confirmed: The note must state that the fascia was incised or that the dissection extended below the plantar fascia. Phrases like “subfascial dissection,” “fascial plane entered,” or “below the investing fascia” satisfy this requirement.
• Multiple areas named: Each drained area must be individually described. “Medial plantar space and lateral compartment drained” is sufficient. “Multiple areas” as a standalone phrase without naming them is not.
• Tendon sheath status documented: The descriptor includes “with or without tendon sheath involvement.” The note should therefore state whether tendon sheaths were explored or opened, even if they were not. This confirms the surgeon evaluated for that component.

Additional documentation elements that strengthen the claim and its audit defense:

• Culture and sensitivity specimens sent (organism identification supports medical necessity)
• Wound irrigation details and packing or drain placement
• Intraoperative findings describing the extent of infection spread
• Pre-operative antibiotic therapy and its clinical effect (or failure) prompting surgical intervention

Structured, complete operative notes support a clean claim submission on the first pass.

Common denial reasons and how to avoid them

CPT code 28003 denials cluster around a handful of root causes. Each is preventable with the right documentation and pre-submission checks.

When a denial arrives, the fastest appeal path is a corrected claim with the updated operative note language attached. For bundling denials, include the NCCI edit and the clinical rationale for unbundling.

Effective denial management workflows log each denial reason by code, which surfaces patterns. If most 28003 denials at one payer are downcodes to 28002, fix the operative note template before questioning payer policy. For the CARC codes on the remittance itself, use our denial codes reference.

How Pabau keeps CPT 28003 claims clean from note to payment

A 28003 claim usually passes through three hands. The surgeon dictates the note, a coder reads it for depth and drained areas, and someone retypes the claim into a clearinghouse portal. Each handoff is a chance to lose the detail that keeps the code from downcoding.

Pabau, the practice management and billing platform we build, keeps those steps in one system. Its digital forms let you build an operative note template that asks for fascial depth, each drained area, and tendon sheath status. The note then supports the code before the claim exists.

Pabau’s billing and claims management turns the invoice into an electronic CMS-1500 claim through the Claim.MD clearinghouse. It runs a real-time eligibility check before submission and tracks the claim’s status with the payer.

When the payer pays, the ERA remittance comes back into Pabau and matches against each claim. A 28003 line paid at a lower rate shows up in the unmatched balance. Your team can then appeal while the operative note is still fresh.

Automate your podiatric billing workflow

Pabau turns invoices into electronic claims through Claim.MD, checks eligibility in real time and brings remittances back into billing. Your team spends less time chasing denials on codes like 28003.

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Conclusion

CPT code 28003 pays for deep, multi-compartment work, so each claim deserves a note that proves it. Start with the operative note template. Once it asks for fascial depth, each named area, and tendon sheath status, the usual downcodes to 28002 and 10060 lose their trigger.

The trade-off is a few extra lines of dictation per case. That costs far less than a corrected claim and an appeal on a procedure with a 90-day global period.

If your team still retypes claims into a clearinghouse portal, connect the note, the invoice, and the claim in one system. Book a demo to see how Pabau sends 28003 claims through Claim.MD and matches the remittance when it pays.

Continue your research

Need to understand how claims clear the payer network? How a medical claims clearinghouse works explains the end-to-end path from claim submission to payer adjudication.

Want to decode the remittance after your 28003 claim processes? Electronic remittance advice (ERA) explained breaks down how to read ERA files and match adjustments to specific denial reasons.

Building a denial prevention protocol for foot surgery codes? Superbill best practices covers how to structure charge capture so CPT codes and ICD-10 pairs are validated before the claim leaves the practice.

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