Allergy and Immunology Billing Cheat Sheet (2026)

Allergy billing has two structures that drive almost every denial: testing is billed per test and the count must be documented, and immunotherapy splits into a separately billed antigen preparation and the injection. Confuse those and you either undercount tests or lose the preparation revenue.

AAPC-Certified
2026 Medicare Fee Schedule
9 Codes Priced

Quick reference for allergy and immunology billers. Last updated .

Top Allergy and Immunology CPT Codes & 2026 Medicare Allowables

CodeDescriptionNon-FacilityFacilityTotal RVU
95004Percutaneous allergy testing, immediate hypersensitivity$3.67$3.670.11
95024Intradermal allergy testing, immediate hypersensitivity$7.68$1.000.23
95044Patch or application allergy test$5.01$5.010.15
95115Allergen immunotherapy, one injection$10.35$10.350.31
95117Allergen immunotherapy, two or more injections$12.36$12.360.37
95165Allergen immunotherapy, antigen preparation, single multi-dose vial$17.37$2.670.52
94010Spirometry$29.73$29.730.89
94060Spirometry, pre and post bronchodilator$43.42$43.421.30
99213Established patient office visit, low MDM$95.19$57.452.85

National 2026 Medicare Physician Fee Schedule estimates (total RVU multiplied by the conversion factor). These are adjusted by state locality. See the per-state table on the Allergy and Immunology billing services page.

Modifiers That Prevent Allergy and Immunology Denials

59 or XU

A distinct service separate from immunotherapy or testing that NCCI would otherwise bundle.

25

A significant, separately identifiable E/M on the same day as testing or an injection. Misused E/M-with-injection-only visits are a top audit target.

76

A repeat test or service by the same physician on the same day with the reason documented.

91

A repeat clinical diagnostic test to obtain subsequent results, not to confirm the first.

GA

An ABN is on file for a service likely to be denied as exceeding frequency or not medically necessary.

JZ

No drug wastage on a single-dose vial where the payer requires the wastage attestation.

Top Allergy and Immunology Denials → Quick Fix

Allergy testing unit count not supportedCO-16

Percutaneous (95004) and intradermal (95024) testing are billed per test. Document the number of tests performed; the count is the units.

Immunotherapy billed without antigen prepCO-16

Antigen preparation (95165) is separate from the injection (95115, 95117). Bill the preparation by the number of doses prepared, plus the injection. Missing the preparation forfeits most of the revenue.

E/M billed with an injection-only visitCO-97

An injection-only visit does not support a separate E/M. Bill the E/M with modifier 25 only when a significant, separately identifiable evaluation occurred and is documented.

Testing exceeds frequencyCO-151

Track payer limits on the number of tests per session and per period. When clinically exceeded, document medical necessity rather than refiling.

Spirometry medical necessity not establishedCO-50

Link the respiratory symptoms or asthma indication for 94010 and 94060. Routine spirometry without an indication is denied.

NCCI Bundling Watch-Outs

Code pairs from this specialty's set that carry NCCI edits. Billing both without a justified modifier triggers a bundling denial.

CodeBundles WithRationale
950040591TCPT Manual or CMS manual coding instruction
950040592TCPT Manual or CMS manual coding instruction
950240591TCPT Manual or CMS manual coding instruction
950240592TCPT Manual or CMS manual coding instruction
950440591TCPT Manual or CMS manual coding instruction
950440592TCPT Manual or CMS manual coding instruction
951150591TCPT Manual or CMS manual coding instruction
951150592TCPT Manual or CMS manual coding instruction

Documentation That Holds Up on Appeal

Allergy testing (95004, 95024)

The number of individual tests performed, since the code is billed per test.

Antigen preparation (95165)

The number of doses prepared from the multi-dose vial, since the unit is the dose.

Immunotherapy injection (95115, 95117)

One injection versus two or more, separate from the antigen preparation.

Same-day E/M

A significant, separately identifiable evaluation distinct from the testing or injection, supporting modifier 25.

Spirometry (94010, 94060)

The respiratory indication and, for 94060, the pre and post bronchodilator results.

Revenue Allergy and Immunology Practices Leave on the Table

$

Undercounting allergy tests because the number performed was not documented.

$

Billing the immunotherapy injection but not the separately payable antigen preparation by dose.

$

Tacking an unsupported E/M onto an injection-only visit, which fails audit and risks paybacks.

$

Frequency denials on testing because the medical necessity for the volume was not documented.

Allergy and Immunology Billing FAQ

How is allergy testing billed?

Per test. Percutaneous (95004) and intradermal (95024) are unit-based, so the documentation has to state the number of individual tests performed; that number is the units billed.

How does immunotherapy billing split?

Antigen preparation (95165) is billed by the number of doses prepared and is separate from the injection (95115 for one, 95117 for two or more). Billing only the injection forfeits the larger preparation component.

Can I bill an E/M with an allergy injection?

Only when a significant, separately identifiable evaluation occurred, with modifier 25 and documentation. An injection-only visit does not support a separate E/M, and routine misuse is a known audit target.

Why is spirometry denied?

Because the respiratory symptom or asthma indication was not documented or linked. Routine spirometry without a clinical indication is denied for medical necessity.

Stop Losing Allergy and Immunology Revenue to Preventable Denials

Our AAPC-certified allergy and immunology coders apply every rule on this sheet to your claims. Call 888-701-6090 for a free billing assessment.