Nephrology Billing Services for ESRD, Dialysis and CKD Care

The Codes a Nephrology Group Bills Most

Modifiers That Matter

Payer Rules to Know

Top Denials in Nephrology Billing Services for Esrd, Dialysis and Ckd Care

What Does Nephrology Billing Cover?

Nephrology billing covers three claim streams: the physician claim for dialysis patients, the physician claim for kidney disease before dialysis, and the claim the dialysis facility sends for the treatments themselves.

The nephrologist's group bills on the CMS-1500. The dialysis facility bills on the UB-04 or the electronic 837 institutional claim. Under the Medicare Claims Processing Manual, Chapter 8, section 10.5, a hospital with a certified renal dialysis facility bills its outpatient ESRD services through that facility on bill type 72x.

ESRD means end-stage renal disease, kidney failure that needs regular dialysis or a transplant. The MCP, or monthly capitation payment, is the single monthly payment Medicare makes to the physician who manages that patient's outpatient dialysis care.

How Is the ESRD Monthly Capitation Payment Billed?

You bill one ESRD monthly code per patient per month, chosen by the patient's age at the end of the month and the number of face-to-face visits that month. Chapter 8, section 140.1, says separate codes exist for one visit, two to three visits and four or more visits, and that the highest payment needs at least four ESRD-related visits.

The age bands and visit counts map to 12 codes. The CMS fee schedule file RVU26D (October 2026) lists all of 90951 through 90970. Most carry payment status A, so Medicare pays them under the fee schedule. 90952 and 90953, for patients under 2, carry status C, so the contractor sets the price.

Section 140.1 defines the month as a calendar month. In the first month, dates run from the day dialysis begins to month end.

Medicare pays the MCP at 80 percent of the approved amount after the Part B deductible, and the patient owes the deductible and 20 percent coinsurance. Section 140.4 tells contractors to pay one monthly payment per patient per month, after the month ends, and to deny duplicate MCP charges.

On the CMS-1500, section 140.3 says box 32 must show the name and address of the facility involved in the patient's maintenance care or training, and box 32a must carry that facility's NPI. Box 24A spans the whole calendar month of responsibility, and box 19 flags self-dialysis training.

See CPT 90960 for the adult four-or-more-visit code.

How Many Visits Are Needed to Bill a Full Monthly Capitation Payment?

A full-visit MCP code for in-center patients needs four ESRD-related, face-to-face visits in the calendar month. The code must reflect the visits actually furnished and documented in the month.

The visits must be face-to-face by a physician, clinical nurse specialist, nurse practitioner or physician assistant. The section lets the MCP physician use others for some visits. Those others must be a partner, an employee of the same group or an employee of the MCP physician, and the same rule covers W-2 employees and 1099 contractors.

• Resident, intern and fellow visits count only if the teaching MCP physician is present.
• Visits to a patient in hospital observation status or living in a skilled nursing facility count.
• Inpatient visits do not count. They are billed with the inpatient visit code.

The physician who does the complete assessment, sets the plan of care and manages the patient bills the monthly service.

How Is Home Dialysis Management Billed?

Home dialysis management is billed with a single monthly code by age, 90963 through 90966, no matter how many visits occur. Section 140.1.1 says the MCP physician must still furnish at least one face-to-face visit a month, though contractors may waive that on a case-by-case basis when the notes show active management.

Patients who switch between home and in-center dialysis during a month are billed on the home dialysis code. Section 140.1.2 says to use the home dialysis per-full-month code whether the patient moved from home to center or the reverse, and whatever the split of the month.

What Happens When a Dialysis Patient Changes Facilities or Doctors Mid Month?

The answer depends on whether the change is temporary or permanent, and on whether the first physician completed the monthly assessment.

For a traveling patient, section 100 says the facility that gives an in-facility treatment bills it, even for a temporary stay. Section 100.1 says the physician who treats the patient away from home marks the claim as a temporary patient, and the contractor adjusts the usual physician's MCP for the absence. That physician bills the per-day code for the days of responsibility (section 140.2.1).

For a permanent change, section 140.2.1 splits it by the first physician's work:

• If the first physician furnished a complete assessment, that physician bills the MCP for the visits furnished and the new physician bills the per-day code for the rest of the month.
• If the first physician did not complete an assessment, that physician bills the per-day code for the days of responsibility and may not bill the MCP that month. The new physician can bill the MCP after a complete assessment, a plan of care and at least one face-to-face visit.

Section 140.3 puts non-continuous dates on separate lines and requires a separate claim when per-day service overlaps two months.

How Do We Bill Hemodialysis for an Inpatient?

Inpatient hemodialysis is billed with 90935 when one physician evaluation is done and 90937 when repeated evaluations are needed, and Medicare pays the procedure code only if the claim's place of service is inpatient hospital. Section 170 explains why: outpatient renal services fall under the monthly payment. Codes 90945 and 90947 are the equivalents for dialysis other than hemodialysis.

Section 160.4 requires the physician to be physically present at some time during the dialysis, and the record must show it,. If the physician visits on a dialysis day but not during the treatment, the claim uses the ordinary hospital visit codes instead. See CPT 90935.

Section 170.B bundles all evaluation and management services into the dialysis code on the same date. Listed exceptions, such as office visits, initial hospital care, consultations and critical care, take modifier 25 when significant and separately identifiable. Section 160.4 narrows this for inpatient dialysis: the visit must be unrelated to the ESRD condition and must be one that could not have been furnished during the treatment.

How Do We Code and Bill CKD Visits Before Dialysis?

Nephrology visits for chronic kidney disease (CKD) before dialysis begins are ordinary visits, billed with office or hospital E/M codes such as 99214, and the CKD stage is reported with a code from category N18. Section 140 excludes all physician services that came before outpatient dialysis started from the monthly payment.

These kidney codes come from the CDC ICD-10-CM code set for fiscal year 2027, effective October 1, 2026. The FY 2027 guidelines assign N18.6 when the provider documents ESRD, and only N18.6 if both a stage and ESRD are documented.

The guidelines say to assign category I12 when hypertension and CKD are both present, unless the provider says they are unrelated, with the N18 code second to give the stage. For a transplant patient with continuing CKD, report the N18 stage and Z94.0.

For the diabetes side see endocrinology billing, and for shared primary care visits internal medicine billing. Venipuncture, code 36415, is listed in RVU26D with status X, so the physician fee schedule does not pay it as a separate service.

How Do We Bill Vascular Access Procedures?

Vascular access procedures are billed separately from the monthly capitation payment, on their own procedure codes. Chapter 8, section 140, part B excludes surgical services such as hemodialysis catheter placement, peritoneal dialysis catheter placement, repair of existing dialysis accesses, thrombolytic therapy and thrombectomy of a clotted cannula from the MCP.

In RVU26D, arteriovenous fistula creation codes 36818 through 36821 and open thrombectomy 36831 carry a 090-day global. Catheter placement 36556 carries 000 and 36558 carries 010. The dialysis circuit codes 36901 through 36906 carry 000, and 36907 and 36909 are add-ons with a ZZZ global.

Section 140 lists interpretation of noninvasive access studies, including 93990, as included in the MCP. Section 140.4 allows separate payment when a physician other than the MCP physician furnishes them. The page for vascular surgery billing covers the surgeon's claim.

How Does a Dialysis Facility Bill Medicare?

A dialysis facility bills Medicare on type of bill 72x with the ESRD prospective payment system (PPS), a single bundled payment per treatment. Chapter 8, section 10, says the PPS covers supplies, equipment, drugs, biologicals, laboratory tests, training and support services for outpatient dialysis in the facility or at home.

The accepted bill types are 721, an admit-through-discharge claim, 722, 723 and 724 for interim claims, 727 to replace a prior claim and 728 to void one. The modality revenue code goes on each line, for example 0821 for hemodialysis.

How Do Medicare, Medicaid and Commercial Plans Differ for Nephrology Claims?

The biggest nephrology-specific rule is the 30-month coordination period. For up to 30 consecutive months, an employer group health plan pays first for a patient with ESRD-based Medicare, and Medicare pays second. The Medicare Secondary Payer Manual, Chapter 2, section 20.1, says the period begins with the earlier of the month a regular course of dialysis starts or, for self-dialysis training, the first day of the month of training.

Medicare pays secondary during those first 30 months of ESRD-based eligibility or entitlement and becomes primary after the 30th month.

Filing limits also differ. Under 42 CFR 424.44(a)(1), a Medicare claim must be filed within 1 calendar year after the date of service. Under 42 CFR 447.45(d)(1), the Medicaid agency must require providers to submit all claims within 12 months of the date of service, and a state may set a shorter window. See our Medicare billing guide and Medicaid billing guide.

Commercial plans set their own filing limits and edits by contract, so we read each payer's policy before billing.

What Are the Most Common Denials in Nephrology, and How Are They Worked?

The denials nephrology groups see most are bundling (CARC 97), another payer responsible (22), missing information (16), duplicates (18) and filing limits (29). A CARC is a claim adjustment reason code, the numeric reason a payer gives on the remittance advice.

The denial table above gives the fix for each. We work denials within 48 hours.

How We Handle Nephrology Billing

We code the monthly ESRD claim from the visit log, send claims within 24 hours of charge entry and work denials within 48 hours. Our certified coders (AAPC and AHIMA) match each visit count to the right MCP code, check the facility NPI and the dates of service, and compare procedure claims against NCCI edits before they leave. We work to a 95% clean claim rate.

For hospital-owned dialysis units we also check UB-04 accuracy: bill type, revenue codes, patient status, condition and occurrence codes, and payer-specific rules.

Our fee is a percentage of collections, shown on our pricing page. To talk through your practice, book a call, or browse all specialties.