Specialty billing
Oncology Medical Billing Services
Oncology billing carries the highest per-claim dollar values in outpatient medicine because of buy-and-bill chemotherapy and biologics. Drug acquisition cost means a single unit-calculation error or an unbilled wastage claim can exceed the value of an entire day of office visits.
Oncology benchmarks
- Typical denial rate
- 13–20%
- Days in AR
- 40–55
- Achievable clean claim rate
- 96%+
Typical ranges for oncology practices. Your actual numbers are measured during the audit.
The complexity
Why oncology is uniquely difficult to bill
Buy-and-bill drugs mean the practice carries acquisition cost before reimbursement
Infusion codes follow a strict hierarchy of initial, sequential and concurrent services
Drug units rarely align with vial sizes, requiring careful calculation and wastage billing
Every regimen change typically requires new prior authorization
Radiation oncology bills planning, simulation, delivery and management separately
Biosimilar substitution changes the billing code entirely
Coding
Oncology procedure codes we work with daily
A representative sample, not an exhaustive list. Coders are assigned by specialty rather than pooled.
| Code | Description |
|---|---|
| 96413 | Chemotherapy administration, intravenous infusion, first hour |
| 96415 | Chemotherapy infusion, each additional hour |
| 96417 | Chemotherapy infusion, each additional sequential infusion |
| 77427 | Radiation treatment management, five treatments |
| 96372 | Therapeutic or diagnostic injection, subcutaneous or intramuscular |
| 77014 | CT guidance for placement of radiation therapy fields |
Revenue leakage
Where oncology practices lose money
These are the denial patterns specific to this specialty — the ones a general-purpose billing service will not be looking for.
Drug unit miscalculation
Units billed by vials rather than by dose administered, producing over- or under-payment on high-cost drugs.
Unbilled wastage
Discarded single-dose vial remainder not billed with the JW modifier, forfeiting reimbursable drug cost.
Infusion hierarchy errors
Initial, sequential and concurrent infusion codes applied in the wrong order or with incorrect unit counts.
Authorization not updated
Regimen changed without obtaining new authorization, denying the entire infusion encounter including drug.
Biosimilar code mismatch
Reference product code billed after a biosimilar was dispensed, or the wrong biosimilar-specific code used.
Payer landscape
What oncology practices need to know about payers
Payer policy drives more oncology denials than coding does. Knowing the policy before the service is what prevents them.
- Buy-and-bill economics mean the practice finances drug acquisition — denial of a single high-cost infusion has direct cash impact, not just revenue impact.
- The JW modifier for discarded drug is required by Medicare for single-dose vials and is among the most commonly forfeited legitimate revenue in oncology.
- Payer preference for specific biosimilars changes periodically and must be tracked per plan.
Questions
Oncology billing FAQ
Last updated August 20, 2026
Reviewed by a certified coding leadBecause HCPCS drug codes bill in defined unit increments that rarely correspond to vial sizes, and oncology drugs are extraordinarily expensive. Units must be calculated from the dose actually administered. A systematic error on a high-cost biologic can exceed the value of an entire clinic day, in either direction.
The JW modifier bills the amount of drug discarded from a single-dose vial after the patient's dose is drawn. It is legitimately reimbursable and required by Medicare, yet frequently omitted because it requires documenting the discarded quantity at the point of administration. It is among the most commonly forfeited revenue in the specialty.
Only one initial service is billable per encounter, and it should be the primary reason for the visit rather than simply the first drug hung. Additional drugs are coded as sequential or concurrent depending on whether they run after or alongside. Applying the hierarchy by chronology instead of clinical primacy is a common and costly error.
Any change to the regimen generally requires fresh authorization. We track authorization against the active regimen rather than against the patient, so a protocol change triggers a new request before the next infusion rather than after a denial.
Primary sources
Coverage, rates and local policy for oncology, at the source.
- Medicare Coverage Database (LCD/NCD) (opens in a new tab)
Centers for Medicare & Medicaid Services — Searchable national and local coverage determinations. The direct answer to whether a diagnosis supports medical necessity for a given procedure.
- HCPCS Level II code set (opens in a new tab)
Centers for Medicare & Medicaid Services — Codes for supplies, drugs, DME and services outside CPT — and the modifier definitions that go with them.
- Medicare Benefit Policy Manual (opens in a new tab)
Centers for Medicare & Medicaid Services — What Medicare covers and under what conditions, as distinct from how a claim is processed. The starting point for any coverage or medical necessity question.
Get a free oncology billing audit
We'll review your oncology denial patterns, coding accuracy and AR aging against the benchmarks above. Takes about two minutes to request.
No setup fees · You pay when we collect · Pricing from 3% of net collections