The rheumatology practice manager who called us on Thursday had a specific problem. Her infusion suite had been giving a newer immune globulin product since January, billing it under an unlisted code with the NDC and a description attached, and getting paid slowly and inconsistently. Her drug vendor rep had just told her the April 2026 HCPCS update had given the product a permanent code as of April 1. She wanted to know whether to rebill the first quarter, whether the Medicare Administrative Contractor would take it yet, and whether her Medicare Advantage plans would follow.
Those are the right questions for the first week of April every year. The April 2026 HCPCS update took effect April 1, 2026, and CMS gave the Medicare Administrative Contractors until April 6 to implement it. Like most second-quarter updates it is not large, but it has a few items that change how specific practices bill, and one retroactive change that some offices will want to act on.
This is what is in the update, who it affects, and the order we work through it with the practices we support.
Key takeaways
- The quarterly HCPCS Level II update effective April 1, 2026 added new permanent codes, mostly J codes for injectable and infused drugs, plus a handful of supply and orthotic codes.
- J1572 (immune globulin, Flebogamma) was reinstated retroactive to January 1, 2026, which means claims billed differently in the first quarter may need review.
- Three upper-extremity prosthetic L codes (L6000, L6010, L6020) were discontinued as of March 31, 2026 with no replacement crosswalk.
- Commercial and Medicare Advantage payers adopt quarterly HCPCS changes on their own schedules, so load the codes but keep the old billing method available for payers that lag.
What the April 2026 HCPCS update changed
A glossary line first: HCPCS Level II codes are the alphanumeric codes, one letter and four digits, that CMS maintains for drugs, biologicals, supplies, durable medical equipment, orthotics and certain services not described in CPT. CMS updates the full code set every January and publishes smaller updates each April, July and October. The April set is the one that catches new drugs approved late the prior year.
The MAC publications for this quarter list new codes across several ranges. The drug additions include J1164 (injection, diltiazem hydrochloride), J1553 (injection, immune globulin, Yimmugo), J9003 (leuprolide injectable, Camcevi), J9183 (gemcitabine intravesical system), J9277 (injection, pembrolizumab with berahyaluronidase alfa), J9278 (injection, carboplatin, Avyxa) and J9601 (injection, linvoseltamab-gcpt). Outside the J range there is A9294 (prescription digital cognitive or behavioral therapy), A4318 (female external urinary collection cup), A4479 (electronic transanal irrigation system), A6548 (accessory to custom gradient compression garment), two powered grip-assist glove codes (A8005 and A8006), L2221 (microprocessor-controlled ankle system) and L5992 (foot shell replacement).
Two codes were revised rather than added: J0174 (lecanemab-irmb) and L6028 (partial hand prosthesis) received updated descriptions. Three codes were discontinued effective March 31, 2026: L6000, L6010 and L6020, all partial hand prostheses, with no crosswalk codes provided. Practices and suppliers that billed those codes should check the revised L6028 description and their DME MAC guidance before submitting April dates of service.
The update also carried a few items that trade publications flagged separately: J1572 (Flebogamma) reinstated with an effective date of January 1, 2026; Q0238 for tocilizumab-aazg (Tyenne) when used for COVID-19 with its associated intravenous administration codes M0233 and M0234; and a change to the co-surgery indicator on CPT 37215 (transcatheter carotid stent with embolic protection) in the fee schedule files. Industry summaries put the total new Level II code count around three dozen once the new proprietary laboratory analysis codes and the hospital outpatient C codes are included.
Who this affects
| Practice type | Codes to look at | What changes |
|---|---|---|
| Oncology and hematology infusion | J9183, J9277, J9278, J9601, J9003 | Move from unlisted J3490 or J9999 with NDC to the permanent code for April dates of service |
| Rheumatology, immunology, neurology infusion | J1553, J1572 | New permanent code for Yimmugo; J1572 valid again back to January 1, 2026 |
| Cardiology and hospital-based practices | J1164, 37215 indicator | Diltiazem injection has a specific code; co-surgery billing on 37215 changes |
| Urology and gynecology | A4318, J9183 | New supply code; intravesical gemcitabine has its own code |
| Orthotic and prosthetic suppliers | L2221, L5992, L6028, L6000 to L6020 | New and revised codes; three deletions with no crosswalk |
| Behavioral health and primary care | A9294 | A code exists for prescription digital therapeutics; coverage still depends entirely on the payer |
Most primary care and general specialty offices will find nothing here that changes daily billing. That is normal for an April update. If you do not administer drugs in the office or supply orthotics, the useful action is confirming that your practice management vendor loaded the file so a stray claim does not reject for an invalid code.
The J1572 retroactive question
When CMS reinstates a code retroactive to January 1, practices that billed the product another way in the first quarter face a choice. If your claims from January through March were paid under an alternative code and the payment was correct for the units given, in our experience there is rarely a reason to disturb them. If claims were denied, pended or paid at an unlisted-code rate that does not reflect the product, a corrected claim (frequency code 7) with J1572 is the clean fix once your MAC has implemented the update.
Do not rebill before the MAC's implementation date. A corrected claim submitted before the code is loaded on the payer side rejects as invalid, and now you have two problems. Check the MAC's article for the update, confirm the implementation date has passed, test with one claim, then release the rest.
For commercial payers and Medicare Advantage plans the answer depends on the payer. Some load CMS quarterly files within weeks; some take a quarter or more; some require you to keep billing the unlisted code with the NDC until their own bulletin says otherwise. Keep a note in the charge master for each new code listing which payers have confirmed acceptance.
What to load and where
The charge master, sometimes called the fee schedule or procedure code table in a practice management system, needs each new code with a description, a default charge, the billing units and the NDC crosswalk. Drug codes are billed in the units defined in the code descriptor, so read the dosage unit in the description before you set the units conversion. A code defined per 1 mg billed as though it were per 10 mg produces either a massive overbill or a Medically Unlikely Edit denial, and both draw attention.
Your EHR's medication administration or infusion module usually has its own mapping from drug product to HCPCS code. That mapping has to be updated separately from the charge master. This is the step most often missed: the billing side loads the code, the clinical side keeps sending the old one, and the interface either drops the charge or sends the unlisted code forever.
Finally, the scrubber and clearinghouse edits. Ask the clearinghouse whether the April 2026 HCPCS file is loaded on their side. If they have not loaded it, valid new codes will reject at the clearinghouse as unknown, and your team will waste hours assuming the code is wrong.
A checklist for the first two weeks of April
- Download the April 2026 HCPCS quarterly update file from the CMS HCPCS quarterly update page and your MAC's companion article.
- Filter the new and revised codes to your specialty and list the products you actually administer or supply.
- Add each relevant code to the charge master with units, description and NDC mapping; update the EHR medication-to-code mapping to match.
- Confirm with the clearinghouse that the April file is loaded.
- For J1572 and any other retroactive change, pull first-quarter claims for the affected products and sort them into paid correctly, paid incorrectly and denied.
- Submit one test claim with each new code to your MAC after the implementation date, then release the rest.
- Check the provider bulletins of your top three commercial payers for their adoption date and note it in the charge master.
If the first-quarter review turns up more than a handful of drug claims paid under unlisted codes at rates that do not match the product, that is worth a closer look at how new drugs enter your billing process generally. It is one of the recurring findings in our revenue leakage reviews for infusion practices, and the fix is a standing quarterly step, not a one-time cleanup.
Questions we hear
Can we bill the new J codes for dates of service before April 1, 2026?
Not unless the code carries a retroactive effective date, as J1572 does this quarter. For the new drug codes that are effective April 1, dates of service in the first quarter stay on whatever code was valid at the time, usually an unlisted code with the NDC.
Our Medicare Advantage plan is still rejecting a new code as invalid. What do we do?
Call provider services and ask for the date they will load the April 2026 HCPCS update, and ask how they want the drug billed until then. Document the answer with a reference number. Then hold those claims rather than letting them reject repeatedly, and release them on the date they gave you.
We never bill drugs. Does this update matter to us?
Honestly, most practices should confirm the file loaded and move on. The one exception is A9294 for prescription digital therapeutics, which some primary care and behavioral health practices are being asked about by patients and vendors. A code existing is not the same as a payer covering it; check the coverage policy before anyone promises a patient it is billable.
What to do this week
- Confirm with your practice management vendor and clearinghouse that the April 2026 HCPCS file is loaded.
- List the new codes that apply to products your office administers or supplies.
- Update the charge master and the EHR medication mapping for each one, including billing units.
- Review first-quarter claims for any product affected by a retroactive change and decide claim by claim whether to correct.
- Record each payer's adoption date as you confirm it, so the July update goes faster.
