Pathology bill after a biopsy: how CPT 88305 units add up

The tissue leaves the room, and so does the billing

The Medicare Claims Processing Manual, chapter 12, section 60, describes surgical pathology as the gross and microscopic examination of organ tissue performed by a physician. Gross examination is the look at the specimen as it arrives: its size, its appearance, how it is cut and which pieces go into a block. Microscopic examination is the read of the stained slides. Both steps sit inside one code family, 88302 to 88309, with 88300 reserved for gross examination alone, and the level within that family depends on the specimen type listed in the CPT code set.

The clinician who takes the biopsy bills for the procedure. The practice that examines the tissue bills for the examination. Those can be the same organization, for example a hospital with its own laboratory and employed pathologists, but very often they are not. A dermatology office may send skin specimens to an independent laboratory; an endoscopy suite may send colon and stomach biopsies to a pathology group that holds the hospital's contract. Each sends its own claim, so each produces its own explanation of benefits and its own statement.

That is why a patient who asked for "the price of the biopsy" before the appointment can still receive a bill from a laboratory name never mentioned at check-in. The quote covered the procedure. The pathology work had not happened yet, and the number of specimens it would involve was not fixed until the procedure was done. The pathology bill is the one layer of a biopsy whose size is set during the procedure itself. Mohs surgery is the exception to the separate laboratory bill: the surgeon reads the stage slides, and the CMS correct coding manual counts that reading inside the stage code, as Mohs surgery cost per stage sets out.

The manual also splits pathology into two halves that can be paid to different parties. The professional component, shown on a claim with modifier 26, is the pathologist's interpretation and report. The technical component, shown with modifier TC, is the laboratory work that produces the slides: processing, embedding, cutting and staining. When one entity does both, it bills the global code with no modifier. When the halves are split, two bills can arrive for the same specimen, one for each half, and neither is a duplicate of the other.

What Medicare counts as one specimen

The rule that sets the unit count is in the CMS National Correct Coding Initiative Policy Manual, chapter X, revision dated January 1, 2026. It states that the unit of service for gross and microscopic surgical pathology, codes 88300 through 88309, is the specimen. It then defines a specimen as tissue or tissues submitted for individual and separate attention, examination and diagnosis, and adds that separate specimens are usually submitted in separate containers.

Two conditions are packed into that definition. The tissue has to be submitted for its own examination and its own diagnosis, which in practice means a separately labelled container. And the manual adds that it must be medically reasonable and necessary to submit the specimens for individual attention. The container is the usual evidence of a separate specimen, not the definition itself. The shorthand "one container, one unit" describes the usual case, and the exceptions run in both directions.

The manual's own example is a colonoscopy that finds two separate polyps, one at 15 centimeters and one at 25 centimeters. It says submitting them as separate specimens may be medically reasonable and necessary, because knowing later which site a given result came from can matter. In billing terms, that is two units of the surgical pathology code. The same paragraph closes the other way: multiple biopsies of the same polyp are usually submitted as a single specimen. Several pieces of tissue from one site, in one container, are one unit.

So the count on a pathology bill tracks how the tissue was divided and labelled at the procedure, which is decided by the clinician taking the samples, not by the laboratory. A bill showing 88305 with four units means the laboratory received four specimens it examined and diagnosed separately. Whether four was the right number is a care question this site does not address. Whether the bill matches the four specimens in the report is a billing question, and it is one you can check.

2026 anchors for 88305 and its neighbors

These are CY2026 Physician Fee Schedule amounts for three surgical pathology levels that bracket 88305. Each figure starts from the relative value units in the October 2026 CMS RVU26D file, weighted by the Michigan Locality 01 indices (work 1.000, practice expense 0.965, malpractice 1.686) and multiplied by the CY2026 conversion factor of $33.4009. Run that way, 88305 lands on the same three amounts the site already stores for it, which is the check on the method. For these codes the CMS file gives one practice expense value with no separate facility figure, so the useful split is not office against facility but professional against technical.

Source: CMS PFS RVU26D and GPCI2026, Michigan Locality 01, CY2026, per unit. Computed and checked October 30, 2026. These are Medicare anchors for one locality, not your bill.

For 88305 the two halves are close to equal: $34.94 for the professional component and $34.08 for the technical component, adding to the $69.02 global figure. That near-even split is specific to this level. At 88307 the technical component is the larger part by far, $195.32 of $271.67, because the specimens at that level take more laboratory work to process. The CMS correct coding manual gives one illustration of where the levels fall: a bone marrow core biopsy taken with a Jamshidi needle is reported with 88305, while a larger bone biopsy taken with a different instrument may be reported with 88307.

The anchor is tied to one Medicare payment locality. The fee schedule amount is the work value times the work index, plus the practice expense value times its index, plus the malpractice value times its index, all times the conversion factor, so the same code pays a different amount in another locality. For 88305 the RVU26D file lists 0.73 work, 1.35 practice expense and 0.02 malpractice units; with every index at 1.000 that is 2.10 units, or $70.14 before geographic adjustment, against $69.02 in Michigan Locality 01. A pathology laboratory in a high-cost metro area and one in a rural locality are paid different Medicare amounts for the identical slide; CMS publishes a Physician Fee Schedule search on its website for anyone who wants their own locality's figure.

Worked arithmetic: one, three and five specimens

The rows below multiply the CY2026 Michigan Locality 01 anchors for 88305 by a specimen count. Nobody's case is being described: one, three and five are round inputs picked so the multiplication is easy to follow. Each column stays inside one payment system and one half of the service, because that is how each claim is priced. The columns are not added across: a laboratory billing the global code does not also bill the halves.

Source: CMS PFS RVU26D and GPCI2026, Michigan Locality 01, CY2026. The last column applies the Part B 20 percent coinsurance to the global column only. Medicare anchors, not your bill.

Each step of the table is one multiplication. Three specimens at $69.02 are $207.06; five are $345.10. If an independent laboratory bills the global code for a person with Original Medicare who has met the $283.00 Part B deductible for 2026, the claims manual's general rule applies: Medicare pays 80 percent of the allowed amount, and the patient's coinsurance is the other 20 percent, which is $41.41 for three specimens and $69.02 for five.

The deductible changes the picture for small pathology bills. The $207.06 allowed for three specimens is less than the $283.00 deductible, so for a person who has not yet met it, the whole allowed amount goes toward the deductible and the patient pays all of it. Pathology bills from early in the year can therefore look out of proportion to the coinsurance figures above. The Medicare Summary Notice, or a plan's explanation of benefits, shows which applied, line by line.

The middle columns matter when the halves are billed by different parties. In a hospital outpatient department, discussed in the next section, the pathologist's group bills only the professional component, so a five-specimen case produces a professional line of 88305-26 x 5, $174.70 in Medicare terms, with 20 percent coinsurance of $34.94 once the deductible is met. The technical half for those specimens is the hospital's line, under a different payment system, and it is not added to the pathologist's figure here.

Where the biopsy happened decides who bills each half

Section 60 of the claims manual sets out who may be paid for the technical half. Fee schedule payment is not made for the technical component when it is bundled into a facility payment, as in hospital inpatient and outpatient settings. Fee schedule payment is made for the technical component in an institutional setting where it is not bundled, and the manual names an ambulatory surgical center as the example. It also says that since July 1, 2012, an independent laboratory may not bill the Medicare contractor for the technical component of a pathology service furnished to a hospital inpatient or outpatient.

Sources: Medicare Claims Processing Manual chapter 12, section 60; CMS PFS RVU26D, Michigan Locality 01; CMS OPPS October 2026 Addendum B. Checked October 30, 2026.

The hospital row needs one more step. In the October 2026 OPPS Addendum B, 88305 carries status indicator Q1 and APC 5671, with a national unadjusted payment of $53.24 and a minimum unadjusted copayment of $10.65, both before wage-index adjustment. CMS defines Q1 in Addendum D1 of the CY2026 final rule as "STV-packaged": the code's payment is packaged when it is billed on the same claim as a code with status S, T or V, paid through a composite APC in certain combinations, and paid separately through its own APC in other circumstances.

The common biopsy procedures sit in that packaging group. In the same addendum, a colonoscopy with biopsy (45380), an upper endoscopy with biopsy (43239), and tangential and punch skin biopsies (11102 and 11104) all carry status T. When the hospital bills the technical half of 88305 on the same claim as one of those procedures, the hospital receives no separate payment for it: it is part of the procedure's APC payment. The pathologist's professional half is still a separate fee schedule claim from a separate group. That is one arrangement behind a "second bill from a group I never met" after a hospital-based endoscopy.

The setting comparison on surgery center versus hospital outpatient cost covers the facility layer of those procedures. Pathology is a layer on top of it in either setting, and it is one more reason a facility quote alone understates the all-in price. How facility fees work explains why a hospital-based service can split into a hospital line and a professional line at all.

Prostate needle biopsies: one unit of G0416

Medicare carves out one common biopsy from the per-specimen rule. Item 10 of section L in the CMS correct coding manual's chapter X says that CMS requires surgical pathology, including gross and microscopic examination, of any and all submitted prostate needle biopsy specimens from a single patient to be reported with one unit of HCPCS code G0416 rather than 88305. The manual notes that its G0416 instructions have changed from year to year, so the 2026 revision is the one that governs 2026 claims.

Sources: CMS PFS RVU26D and GPCI2026, Michigan Locality 01, CY2026; CMS OPPS October 2026 Addendum B, national unadjusted rates before wage-index adjustment. Checked October 30, 2026. Medicare anchors, not your bill.

The arithmetic shows why the separate code exists. Take a stated input of 12 prostate specimens, each in its own container. Under the general rule that would be 88305 x 12, which comes to $828.24 at the Michigan Locality 01 anchor. Under the G0416 rule the same 12 specimens are one unit, $350.99. G0416 is valued as one service for all submitted specimens, so its anchor sits between one unit of 88305 and twelve. Neither number is a price anyone pays; together they show how much the unit rule moves a pathology line.

On the hospital side, G0416 carries status Q2 in the October 2026 addendum, APC 5673, with a national unadjusted payment of $366.21 and a minimum unadjusted copayment of $73.25. Addendum D1 defines Q2 as packaged when billed on the same claim as a status T code and paid separately otherwise. The CY2026 prostate biopsy procedure codes 55705 to 55709 are listed with status J1, a comprehensive APC, under which the other covered Part B services on the claim are packaged into the procedure payment, with the exclusions listed in Addendum J.

G0416 is a Medicare HCPCS code, and the correct coding manual is a Medicare document. A commercial plan applies its own coding policy, which may follow Medicare's or may accept 88305 with a unit count. A self-pay bill follows whatever the laboratory charges. If a prostate biopsy is coming up and you will pay part of the pathology line yourself, ask the laboratory which code it will bill and whether its price is per specimen or per case.

Stains ordered after the first read

Some pathology bills grow after the first examination, because the pathologist orders additional stains on the same tissue. Those are separate codes with their own unit rules, and they are a common reason for a second or larger pathology bill from the same laboratory. Whether a stain is needed is a decision for the clinicians; the unit rules for each stain code are what reach the bill.

Source: CMS PFS RVU26D and GPCI2026, Michigan Locality 01, CY2026. Unit rules from the NCCI Policy Manual chapter X, section M. Checked October 30, 2026. Medicare anchors, not your bill.

For special stains, codes 88312 to 88319, the correct coding manual says the unit of service is each stain. The same stain on a second specimen, or on a second block of tissue from the same specimen, can be a second unit. Multiple levels cut from one block and stained with the same stain are one unit, and the manual says so directly, because cutting several levels from a block is common practice. Control slides run alongside a stain are not separate units either. As an illustration with a stated input, one special stain on two specimens would be 88312 x 2, or $214.12 at the Michigan Locality 01 global anchor.

For immunohistochemistry, codes 88342, 88341 and 88344, the unit is each antibody stain procedure per specimen. Code 88342 is the first single antibody on a specimen, and 88341 is an add-on for each additional single antibody on the same specimen; the RVU26D file lists 88341 with the global period ZZZ, which its documentation defines as a code related to another service and always included in that service's global period. One antibody run on several blocks from one specimen is still one unit for that specimen. As an illustration, two antibodies on one specimen would be 88342 plus 88341, $199.42 global in Medicare terms, of which $59.29 is the professional half.

In a hospital outpatient department, the technical half of these stains follows the packaging rules again. The October 2026 addendum lists 88312 as status Q1, APC 5671, $53.24; 88342 as status Q2, APC 5672, $174.06; and 88341 as status N, packaged with no separate payment. Those are national unadjusted figures before wage-index adjustment. The pathologist's professional half of each stain is billed under the fee schedule on its own claim.

A second-opinion review is billed differently again. When slides prepared and read at one laboratory are sent to a pathologist at a different location, the review uses consultation codes 88321 to 88325, and the correct coding manual says those are reported with one unit of service regardless of the number of specimens, blocks or slides. A consultation line on a bill is therefore a single unit for the whole case.

Out-of-network pathologists and the facility test

For people with group or individual health coverage, the federal No Surprises Act rules decide whether an out-of-network pathology bill can exceed in-network cost sharing, and the answer depends on where the biopsy was done. Under 45 CFR 149.420(a), a nonparticipating provider who furnishes covered non-emergency services at a participating health care facility may not bill more than the in-network cost-sharing amount. Paragraph (b)(1)(i) lists items and services related to pathology among the ancillary services for which the notice-and-consent exception never applies, so a waiver signed at check-in does not change the limit for a pathology bill.

The protection attaches to the facility, and 45 CFR 149.30 defines a health care facility for non-emergency services as a hospital, a hospital outpatient department, a critical access hospital or an ambulatory surgical center. A physician office is not on that list. So the same out-of-network laboratory bill is limited to in-network cost sharing after a biopsy at an in-network hospital outpatient department or surgery center, and is not covered by that rule after a biopsy done in an office. Paragraph (b)(1)(iii) separately lists diagnostic services, including laboratory services, among the services where notice and consent does not apply, again within the facility setting.

When the protection applies, the plan should process the pathology claim with in-network cost sharing, and the explanation of benefits should show the patient share on that basis. The balance billing guide walks through the full test and what to send if a bill exceeds the in-network amount. Original Medicare works differently: these rules apply to private coverage, and Medicare's own billing limits for participating and nonparticipating physicians govern a Medicare patient's pathology bill.

Your share on each kind of coverage

With Original Medicare, surgical pathology is a physician service paid under the fee schedule, so the Part B deductible and 20 percent coinsurance apply to it, as the worked rows above show. That is a difference from many clinical laboratory tests on blood or urine, which Medicare prices under its clinical laboratory fee schedule. The lab fee schedule guide explains those, and why a pathology line and a blood test line on the same statement can be treated differently.

With a commercial plan, the per-unit amount is the plan's contracted rate with that laboratory, and your share follows the plan's deductible and coinsurance rules. Network status is the variable to check, because the laboratory is chosen by the clinician's office, not by you. Before the procedure, ask the office which laboratory or pathology group will read the tissue, then ask the plan whether that group is in network. If the biopsy came out of a screening colonoscopy, why a preventive visit came with a bill covers the federal guidance on which items count as part of the screening and how to raise a pathology charge with a plan.

Paying yourself is where the unit question is hardest to answer in advance, because the specimen count is not known until the procedure is over. Ask the laboratory for its self-pay price per unit of 88305, and for its prices for the stain codes, so the bill can be checked once the count is known. If you are uninsured or not using insurance and the procedure is scheduled at least three business days ahead, you are entitled to a Good Faith Estimate from the scheduling provider. The Good Faith Estimate guide explains why a separate pathology group may not appear on that estimate in 2026 and how to request one from the laboratory directly.

A useful sentence for the laboratory's billing office, before or after the procedure: "Please tell me your price for CPT 88305 per specimen, for 88342 and 88341 per stain, and whether you bill global or professional only for a procedure at [facility]." That one question covers the unit price, the add-on prices and which half of the service will reach you from that office.

Matching the pathology bill to the report

Pathology bills are unusually easy to check, because the unit count has a document behind it. Each specimen gets its own diagnosis under the correct coding manual's definition, so the pathology report lists the specimens the laboratory received and a diagnosis for each one. Ask your clinician's office or the patient portal for the report, and ask the laboratory for an itemized statement with codes and units.

A mismatch becomes a precise question: "The report lists three specimens; the statement shows 88305 with four units. Please identify the fourth specimen or correct the bill." Put it in writing and keep the date. For a Medicare prostate biopsy billed as 88305 with several units, the question is whether G0416 should have been billed instead. For a plan claim, the same numbers appear on the explanation of benefits, where reading an explanation of benefits shows the allowed amount and your share per line.

Keep the laboratory statement next to the procedure bill and the facility bill for the same date. If the laboratory bill arrives months later or a line still does not match after your question, the itemized bill check covers how to request the statement and dispute a line, and the same approach works for a laboratory as for a hospital.

Questions on specimen counts and pathology charges

Coding manual, fee files and federal rules used

• CMS, NCCI Policy Manual for Medicare Services, chapter X, Pathology/Laboratory Services, revision date 1/1/2026: section L items 2, 9 and 10 (consultation codes, gross examination, G0416 for prostate needle biopsies) and section M items 8 and 9 (specimen as the unit of service, the specimen definition and polyp example, special stain and immunohistochemistry units), plus the bone marrow and bone biopsy levels. Checked October 30, 2026.
• CMS, Medicare Claims Processing Manual, chapter 12, section 60 (payment for pathology services: professional and technical components, settings, independent laboratories) and section 20 (allowed charge and the 80 percent payment rule). Checked October 30, 2026.
• CMS, Physician Fee Schedule relative value file RVU26D (October 2026 release) and CY2026 GPCIs, Michigan Locality 01, $33.4009 conversion factor: every PFS global, 26 and TC anchor in the tables and worked rows. Computed October 30, 2026.
• CMS, OPPS October 2026 Addendum B (status indicators, APCs, national unadjusted payments and copayments for 88304, 88305, 88307, 88312, 88341, 88342, G0416, 11102, 11104, 43239, 45380 and 55705 to 55709). Checked October 30, 2026.
• CMS, CY2026 OPPS final rule addenda, Addendum D1, definitions of status indicators Q1, Q2, N and J1. Checked October 30, 2026.
• eCFR, 45 CFR 149.420, balance billing for non-emergency services at participating facilities, including the ancillary services list, and 45 CFR 149.30, definition of health care facility. Checked October 30, 2026.
• Medicare.gov, Medicare costs, 2026 Part B deductible of $283.00. Checked October 30, 2026.

General billing information, not medical, legal or insurance advice. Medicare anchors are not your bill, and a laboratory's own charges and a plan's allowed amounts can differ widely from them. Confirm your price in writing before service.