HCPCS code P9603 – Phlebotomist travel allowance (per mile)

Key takeaways

HCPCS code P9603 is the per-mile travel allowance for medically necessary laboratory specimen collection from a homebound or nursing home bound patient.

P9603 and P9604 are two separate payment bases, and a trip is billed on one or the other. P9603 pays per eligible mile, while P9604 pays a flat, prorated trip charge.

Use P9603 when the round trip to one location runs over 20 eligible miles. It also applies to any trip covering more than one location.

For CY 2026 the per-mile rate is $1.25. The total is prorated across the Medicare patients whose specimen collection fee is payable, with one claim per patient.

From April 1, 2026, P9603 mileage is billed to the tenth of a mile for trips under 100 eligible miles.

Pabau, the practice software we build, keeps the order, the homebound note, and the claim on one patient record. A mileage line can then be evidenced months later.

HCPCS code P9603: Definition and code details

HCPCS code P9603 is the Medicare travel allowance code billed on a per-mile basis.

It pays for a trained technician, typically a phlebotomist, to travel to a homebound or nursing home bound patient and collect a specimen.

Its official descriptor, quoted in full in the table below, ends with the words prorated miles actually traveled. Those words mark the per-mile basis. Its companion, HCPCS code P9604, ends with “prorated trip charge” instead.

Among HCPCS codes, P9603 sits in the Level II P-series, which covers pathology and laboratory services. CMS sets the rules in the Medicare Claims Processing Manual, Chapter 16, section 60.2, last revised by Transmittal 13746, effective April 1, 2026.

What P9603 covers and what it does not

P9603 covers the transportation and personnel cost of sending a trained technician out to collect a specimen. Three conditions have to hold before the code is payable at all.

• A specimen collection fee is payable for that patient. The travel allowance rides on the collection fee. If no collection fee is due, no travel allowance is due either.
• The patient is homebound or nursing home bound. The home draw is also documented as medically necessary. For a facility patient, the allowance applies only when no qualified staff are on duty to draw.
• A trained technician personally drew the specimen. A courier who only picks up a specimen someone else drew earns neither fee.

Eligible miles start at the laboratory, or wherever the technician’s collection travel begins, and end where that travel ends. Miles driven for any other purpose are excluded. That includes miles to a non-Medicare patient, miles to a stop where no specimen was collected, and personal detours.

Four situations fall outside the code.

• A draw performed at a drawing station or in a physician office.
• A home visit arranged for convenience rather than medical necessity.
• A specimen pickup that needs only a messenger.
• A short trip of 20 eligible miles or less to one location, which is billed under P9604.

P9603 vs P9604: Per mile or flat rate

P9603 and P9604 are two separate payment bases, and each trip is billed on one basis or the other. Neither code covers a “first mile”, and neither is an add-on for extra miles.

CMS decides the basis from two facts about the trip: how many eligible miles it ran, and how many locations the technician visited. A short four-mile trip to one patient and back is a single P9604 flat trip charge, not P9603.

Worked examples of the per-mile basis

CMS works both of these examples in the manual at the older CY 2024 rate. The figures below apply the CY 2026 rate of $1.25 per mile, published in MLN Matters article MM14345.

One location, more than 20 eligible miles

A technician drives 45 miles from a city laboratory to a rural skilled nursing facility. Blood is drawn from six Medicare patients, and the technician drives the same 45 miles back.

The round trip comes to 90 eligible miles, which is more than 20, so the per-mile basis applies. Ninety miles at $1.25 gives $112.50. Divided across six patients, each claim carries $18.75 under P9603.

More than one location

A technician drives 40 miles to a Medicare patient and draws blood. Next comes a 10-mile leg to a non-Medicare patient, then 20 miles to two Medicare patients for catheter urine specimens. The last leg is 20 miles back to the laboratory.

The trip covers more than one location, so the per-mile basis applies regardless of distance. The 10 miles to the non-Medicare patient are left out, which leaves 80 eligible miles. At $1.25 that is $100.00, or $33.33 on each of the three claims.

Set side by side, both routes run through the same three steps: total the eligible miles, apply the rate, then divide by the payable patients.

Billing P9603 to the tenth of a mile

Change Request 14130 changed how P9603 mileage is reported for dates of service from April 1, 2026. MACs now accept decimal mileage on this code, and only on this code.

• Under 100 eligible miles: round up to the nearest tenth of a mile and show the decimal, for example 13.7 or 99.9.
• Under 1 eligible mile: enter a zero before the decimal, for example 0.9.
• 100 eligible miles or more: report a whole number with no decimal, so 998.5 miles is reported as 999.

Older claim templates that force whole-mile units will now under-report short trips. Check that your billing system accepts a decimal in the units field before the first post-April claim goes out.

How to bill HCPCS code P9603: Step by step

Billing this code correctly is mostly a matter of recording the trip while it happens. The steps below follow one route from order to submission.

1. Confirm the patient qualifies. Obtain the order and the clinical documentation showing the patient is homebound or nursing home bound. The record should show the home draw is medically necessary on this date.
2. Confirm a collection fee is payable. Blood drawn by venipuncture and urine collected by catheterization qualify. Only one collection fee is allowed per patient encounter.
3. Log the trip as it runs. Record the date, each address visited, whether a specimen was collected there, and the mileage. Electronic mileage records are acceptable if they can be shared with your MAC.
4. Total the eligible miles. Count the miles to each location where a Medicare patient received collection services, plus the miles back. Leave out legs to non-Medicare patients and any personal detour.
5. Pick the basis. More than 20 eligible miles to one location, or more than one location, is P9603. Twenty eligible miles or less to and from one location is P9604.
6. Calculate and prorate. Multiply the eligible miles by the mileage rate, then divide by the number of Medicare patients whose collection fee is payable.
7. Submit one claim per patient. Each claim carries P9603 and the collection code, such as CPT code 36415 for venipuncture. Report the mileage to the tenth where the trip was under 100 eligible miles.

Ask your MAC how it wants the prorated mileage shown in the units field, since contractor billing articles differ on the detail. The collection fee is what makes the travel allowance payable, which is why the two lines are prepared together.

Required documentation for P9603 claims

Per-mile claims depend on the trip record more than any other lab line. Four elements carry most of the weight in a review.

• The order. A signed order for the test, with documentation that the patient is homebound or nursing home bound and why a home draw is needed.
• Medical necessity on each date. A standing order on its own rarely satisfies a reviewer. Each date of service should show the patient still met the criteria.
• The trip log. Date, addresses in order, whether a specimen was drawn at each stop, mileage per leg, and the technician who traveled. This supports both the basis and the eligible-mile total.
• The proration worksheet. Keep the count of patients used as the divisor for that trip. Without it, a reviewer cannot reconcile the amount on any single claim.

Submitting a clean claim for a travel allowance starts at dispatch. A log written then holds up far better than mileage reconstructed from memory at billing time.

Common P9603 denial reasons and how to avoid them

Denials on this line cluster around a short list of causes, and most trace back to the trip record rather than the code. Strong denial management treats travel allowance denials as their own category.

Medicare Advantage and private payer coverage

P9603 is a Medicare construct, and commercial payers are not bound to it. Some plans recognize the code and pay their own amount. Others fold travel into the collection fee, and some do not cover home collection at all.

• Verify before the first trip. Ask the plan whether P9603 is payable, at what amount, and what documentation it wants.
• Do not assume Medicare criteria carry over. A plan may define homebound differently, may not prorate, or may require prior authorization for home collection.
• Medicare Advantage. These plans cover Medicare-covered services, so the travel allowance is in scope when the criteria are met. Claim submission rules still follow the plan, not the MAC.

Keeping mileage claims audit-ready with Pabau

Long routes are often reconstructed after the fact. The mileage sits with the courier, the homebound note sits in the chart, and the patient count sits in someone’s head. When a reviewer asks about one $18.75 line a year later, assembling the answer costs more than the claim paid.

In Pabau, the order, the clinical note, the visit date, and the submitted codes sit on the same patient file. The evidence for each mileage line is gathered while the visit is fresh.

Pabau’s claims management supports insurance billing in the US, the UK and Australia. Each claim’s status is tracked against the patient record, from submission through to paid. Repeated denials on travel lines then sit side by side, so a pattern is spotted after a handful of claims.

Keep mileage evidence attached to every lab claim

Pabau keeps orders, clinical documentation, and billing records on one patient file. Per-mile travel allowance claims can then be evidenced long after the route was driven.

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Conclusion

Every P9603 claim stands or falls on the trip record. Choosing between the per-mile and flat-rate basis is simple once the eligible miles and the stops are known.

So set the trip log up before the next route goes out. Capture the addresses in order, whether a specimen was drawn at each stop, the miles per leg, and the patient count. Then confirm your billing system takes a decimal in the units field.

With those facts recorded at dispatch, a reviewer’s question two years later takes minutes to answer. Book a demo to see how Pabau keeps that evidence on the patient record it belongs to.

Continue your research

Billing a short trip to one location? HCPCS code P9604 explains the flat-rate travel allowance and the 20-mile test in full.

Need the collection code that carries the travel line? CPT code 36415 covers venipuncture billing and its documentation.

Working through a stack of remittance denials? Denial codes in medical billing maps the common reason codes onto their fixes.

Want a broader framework for reducing claim errors? Denial management in healthcare walks through the denial lifecycle from identification to resubmission.

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