HCPCS code A4708 – Acetate concentrate solution for hemodialysis

Key takeaways

HCPCS code A4708 reports acetate concentrate solution for hemodialysis, per gallon.

Bicarbonate concentrate (A4706, A4707) and acid concentrate (A4709) have their own codes, so the product label decides which one you bill.

A4708 is on the CMS ESRD PPS consolidated billing list, so it is bundled into the facility’s payment for in-center and home dialysis alike.

A4714 is treated water for peritoneal dialysis, not a dialysate concentrate, and is never interchangeable with A4708.

Pabau’s claims management software checks each claim for missing details before it goes out and tracks its status through to payment.

HCPCS code A4708: Official descriptor and code definition

The Centers for Medicare and Medicaid Services (CMS) defines HCPCS code A4708 as “Acetate concentrate solution, for hemodialysis, per gallon.” The code sits within the HCPCS Level II alphanumeric system, which CMS maintains for products, supplies, and services that CPT codes do not describe.

Check the descriptor against the current CMS HCPCS Alpha-Numeric file before billing. Wording and status can change with each annual HCPCS update.

The code falls in the A4000-A4999 series, which covers medical and surgical supplies. The dialysis machine mixes concentrate with treated water to make the dialysate that passes through the dialyzer. A4708 covers the acetate form of that concentrate, and one unit equals one gallon.

What A4708 covers and what it does not

A4708 covers acetate concentrate solution for hemodialysis, reported per gallon. It does not cover bicarbonate concentrate, acid concentrate, or any peritoneal dialysis supply, since each of those has its own HCPCS code.

The table below sets out what falls inside and outside A4708, line by line.

A4708 vs other dialysate concentrate codes: Choosing the correct code

Four HCPCS codes describe hemodialysis concentrate, and they split on two variables: Concentrate type and billing unit. A4708 is the only one for acetate concentrate. Bicarbonate concentrate takes A4706 as a solution or A4707 as a powder. The product label and the delivery record decide the code, whether dialysis runs in-center or at home.

A4714 sits close by in the A47xx range, so coders sometimes treat it as a dialysate code. It is not interchangeable with A4708, because A4714 reports treated water (deionized, distilled, or reverse osmosis) for peritoneal dialysis, per gallon.

The chart below puts both decisions in one place: Which code the label points to, and which claim carries it for an ESRD patient.

How Medicare pays for A4708 under the ESRD PPS

A4708 appears on the CMS ESRD Prospective Payment System (PPS) consolidated billing list. Medicare pays for acetate concentrate through the ESRD facility’s bundled per-treatment payment, not as a separate line item.

The bundle covers home dialysis too. Since the ESRD PPS began in 2011, the ESRD facility is responsible for home dialysis supplies. The separate supplier route (Method II) no longer exists. A vendor that delivers concentrate to a home patient is paid by the facility under arrangement, not by Medicare.

Because Medicare bundles A4708, there is no separate fee schedule amount to collect for an ESRD patient. CMS updates the ESRD PPS consolidated billing list regularly, so check it each payment year.

Consolidated billing works the same way for A4770, the vacuum tubes used to draw blood samples from dialysis patients. Medicare does not price those tubes separately either.

Billing HCPCS code A4708 for home hemodialysis patients

Home hemodialysis changes who delivers the concentrate. Responsibility stays with the ESRD facility that manages the patient’s home program, which keeps the supply inside its bundled payment under consolidated billing.

1. Confirm home hemodialysis status. The patient’s chart must document that hemodialysis is performed at home and that a physician has approved the home modality. A home hemodialysis training record or written order is typically required.
2. Identify the responsible facility. The ESRD facility that supports the home program submits the Medicare claim. A vendor that ships concentrate is paid by that facility under its arrangement.
3. Flag the home setting on the facility claim. Home dialysis is reported on the facility’s institutional claim, with the home condition code (such as condition code 74) your MAC specifies. Do not file a separate professional or DME claim for the concentrate.
4. Report units accurately. One unit of A4708 equals one gallon. Bill only the quantity actually delivered and documented in delivery records.
5. Watch for consolidated billing edits. Medicare rejects a supplier or professional claim for an item on the consolidated billing list when the patient has ESRD. If a vendor bills A4708 directly, expect a denial and route the item through the facility.

Documentation requirements for A4708 claims

Because Medicare bundles A4708, documentation protects the facility on audit rather than unlocking a separate payment. Commercial and Medicaid payers that pay the code separately will also ask for these records. Assemble them before submission, not after a denial arrives.

Strong medical billing compliance practice for A4708 requires the following documentation on file:

• Physician order. A written, signed dialysis prescription from the treating nephrologist that names the modality, the setting, and the concentrate used.
• ESRD diagnosis codes. ICD-10-CM codes documenting end-stage renal disease (N18.6 is the primary ESRD code; Z99.2 documents dependence on renal dialysis). Confirm payer-specific medical necessity criteria, as pairing requirements vary by payer and MAC jurisdiction.
• Delivery records. Signed proof-of-delivery records showing the quantity delivered to the patient, the delivery date, and the patient’s or caregiver’s acknowledgment of receipt.
• Concentrate type on record. The prescription and delivery records should name acetate concentrate. That lets an auditor match the record to A4708 rather than A4706, A4707, or A4709.
• Supplier arrangement. For home patients, keep the written arrangement with any vendor that delivers concentrate on the facility’s behalf.

Keep documentation organized in the patient’s supply file, as payers may request records on post-payment audit. Tracking which home dialysis patients still lack an order or a delivery record is easier in claims management software than in a spreadsheet.

Modifiers used with HCPCS code A4708

Because the ESRD facility reports A4708 inside its bundled payment, the line rarely needs a modifier. The modifiers below are the ones that come up when a payer or a claim edit questions the item.

DMEPOS modifiers such as KX, NU, RR, and UE do not apply to a consumable billed under the ESRD bundle. Adding them to an A4708 line signals a supplier claim that Medicare does not expect.

Modifier applicability varies by MAC jurisdiction and payer. Confirm current requirements against your billing MAC’s local coverage determination (LCD) and AAPC’s HCPCS code reference before submitting.

Common denial reasons for A4708 and how to prevent them

Most A4708 denials trace back to the six causes below. Structured denial management catches each one before submission, which cuts the rework cycle.

• Wrong code selection (A4708 vs other concentrate codes). Billing A4708 for bicarbonate or acid concentrate misstates the supply and fails audit. So does mistaking A4714, which is peritoneal dialysis water, for a dialysate code. Prevention: Match the code to the concentrate type and unit on the delivery record.
• Missing or unsigned physician order. A4708 claims without a signed order in the file fail on audit and increasingly on first submission as payers automate documentation checks. Prevention: Require the physician order before delivery, not at billing time.
• Bundling errors. Billing A4708 separately for an ESRD patient triggers a consolidated billing denial, whether dialysis happens in-center or at home. The supply sits inside the ESRD PPS payment. Prevention: Route every dialysis supply through the facility claim.
• Incorrect units of service. Reporting units that exceed the quantity documented in delivery records, or misunderstanding the unit definition for this code, results in overpayment and potential audit risk. Prevention: Bill only the units confirmed in signed delivery records.
• Misused modifiers. Adding DMEPOS modifiers such as KX or NU, or using AY on a dialysis supply, invites edits and audit questions. Prevention: Build modifier checks into the pre-submission workflow.
• Unsupported diagnosis codes. Submitting A4708 without an ESRD diagnosis code that payers recognize as medically necessary triggers medical necessity denials. Prevention: Pair A4708 with the appropriate ICD-10 codes (see next section) and confirm against applicable LCDs.

To stop repeat supply code denials, map each rejection to its denial codes and track which root cause keeps coming back.

ICD-10 diagnosis codes commonly paired with A4708

Payers expect A4708 claims to carry diagnosis codes that document the underlying ESRD and the patient’s dependence on dialysis. The codes below are those most commonly accepted alongside A4708. Medical necessity criteria vary by MAC jurisdiction, so confirm the applicable local coverage determination before billing.

ICD-10 pairing requirements are payer-specific and can change when CMS issues new Local Coverage Determinations. Review applicable LCDs through the Medicare Informatics HCPCS tables or your MAC’s coverage database to confirm accepted diagnosis codes for A4708 in your region.

How Pabau helps billing teams submit clean A4708 claims

Many dialysis billing teams track concentrate deliveries, physician orders, and payer rules in separate spreadsheets. That split is how a vendor ends up billing A4708 directly, or a delivery record goes missing before an audit.

Pabau, the practice management platform we build, keeps claims beside the calendar, patient records, and invoices. In the US it connects to Claim.MD, so you can check eligibility, submit claims electronically, and post ERA remittances from one dashboard.

Validation checks run every time you send a claim, flagging missing details such as membership numbers or authorization codes. Each claim then moves through clear stages, from pending to paid or error, so a rejected supply line surfaces the day it comes back.

Keep dialysis supply claims on track

Pabau checks each claim for missing details before it goes out and tracks its status through to payment. Your team can fix a rejected A4708 line the day it comes back.

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Conclusion

Code A4708 from the product label every time. Acetate concentrate is A4708, bicarbonate and acid concentrates go to A4706, A4707, or A4709, and A4714 water never belongs in this decision.

For a Medicare patient with ESRD, the claim route matters more than the code. Every gallon belongs on the facility’s claim, in-center or at home, so keep vendor arrangements and delivery records ready for the audit that eventually comes.

Book a demo to see how Pabau keeps dialysis supply claims, invoices, and patient records in one place for your billing team.

Continue your research

Want to understand how denials are categorized across your claims? Denial codes in medical billing explains how CARC and RARC codes map to denial root causes, helping billing teams fix patterns rather than individual claims.

Looking for a structured billing compliance checklist? Medical billing compliance covers the documentation, auditing, and payer-specific requirements that keep dialysis supply claims clean.

Need to understand the full revenue cycle behind supply code billing? What is medical billing walks through how HCPCS supply codes move from clinical documentation to collected payment.

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