CPT code 94070 – Bronchospasm provocation evaluation

Key takeaways

CPT code 94070 covers a bronchospasm provocation evaluation, with multiple spirometric determinations recorded around an administered challenge agent.

Spirometry performed within the protocol (94010) is bundled into 94070. A 94060 bronchodilator study is normally bundled too, unless it is a distinct, documented service.

Administration of the provoking agent is reported separately with 95070 or 95071, not inside the 94070 payment.

Documentation must show the agent and dose, results at each measurement interval, and a signed physician interpretation.

Pabau sends US claims through Claim.MD and warns staff when a prior authorization is missing from the patient’s case.

CPT code 94070: Official descriptor and clinical scope

CPT code 94070 reports a bronchospasm provocation evaluation, the challenge test used to confirm or rule out airway hyperresponsiveness.

The official AMA CPT code set descriptor reads: “Bronchospasm provocation evaluation, multiple spirometric determinations as in 94010, with administered agents (eg, antigen[s], cold air, methacholine).” Three words carry the most billing weight: “multiple spirometric determinations.” The code covers the full serial evaluation across several time intervals, not a single post-challenge measurement.

The technician records baseline spirometry, the provoking agent is given in a controlled setting, and FEV1 and FVC are measured at set intervals.

Measurements typically repeat every 3 to 5 minutes until a significant response occurs or the protocol ends. 94070 covers that serial spirometry and its monitoring as one unit. Administering the agent is reported separately, with 95070 for methacholine or histamine and 95071 for antigens or gases.

What is included and excluded from CPT 94070

Bundling decides whether a 94070 claim pays cleanly. The serial measurements belong to 94070, so the individual 94010 readings taken during the protocol never go on the claim. The agent, the baseline study and a split interpretation each follow their own rule, as the chart below shows.

Included in the 94070 payment:

• All serial spirometric measurements performed during the challenge protocol
• Patient monitoring throughout the procedure
• Reversal of bronchospasm when indicated (albuterol or equivalent)

Reported separately:

• Administration of the provoking agent: 95070 for methacholine or histamine, and 95071 for antigens or gases.
• Physician interpretation billed with modifier 26, when a facility and a physician group split the technical and professional components.

Normally bundled, payer-dependent:

• A pre-challenge baseline study. NCCI edits normally bundle 94060 into 94070, so it is reported only as a distinct, documented service with a modifier. Check the current NCCI procedure-to-procedure table and the payer’s policy before billing it.
• The methacholine itself. Some payers pay the drug under its HCPCS J-code, while others treat it as a supply. Verify with the payer before submission.

If the physician needs a bronchodilator response test on a different encounter, bill 94060 on its own claim. On the same date, keep the documentation that shows why it was a separate service.

Never separately billable:

• Individual spirometry measurements (94010) performed as part of the provocation protocol

Documentation requirements for CPT 94070

Incomplete documentation is a frequent reason 94070 claims are denied or recouped on audit. The medical record should contain each of the following before the claim goes out.

• Indication for testing: A specific diagnosis or clinical question that justifies the bronchospasm provocation evaluation (e.g. suspected asthma, unexplained cough, occupational exposure).
• Provoking agent: The specific agent administered (methacholine, histamine, cold air, exercise), the dose or concentration used, and the protocol followed.
• Serial measurement log: FEV1 and FVC values recorded at each interval. A single post-challenge measurement does not satisfy the “multiple spirometric determinations” requirement in the code descriptor.
• Patient response and outcome: The percentage fall in FEV1 at each interval and the determination of whether the challenge was positive, negative, or inconclusive.
• Physician supervision notation: Who supervised the test and how they were available to intervene. Verify the current MPFS supervision indicator for 94070 and your MAC’s policy, which set the level Medicare requires.
• Signed physician interpretation: A written interpretation of the results, signed by the physician. It is distinct from a technician note, and payers expect it whenever the professional component is billed.

ICD-10 diagnosis codes to pair with CPT 94070

Pairing CPT code 94070 with an unsupported ICD-10 code is the fastest way to trigger a medical necessity denial. Many payer policies for pulmonary function testing carry an approved diagnosis list, and claims with a code outside it are denied on the first pass.

Always cross-reference against the applicable Medicare Administrative Contractor (MAC) LCD for pulmonary function testing. The diagnosis code list varies by region, and a code one MAC accepts may trigger a denial with another. A payer grid that maps each ICD-10 code to the payers and MACs accepting it for 94070 keeps that check quick.

Medicare and payer reimbursement for CPT 94070

CPT code 94070 carries separate facility and non-facility payment rates under the Medicare Physician Fee Schedule (MPFS). Non-facility rates apply when the procedure is performed in a physician’s office. Facility rates apply in a hospital outpatient department or ambulatory surgical center. Verify current-year figures using the CMS Physician Fee Schedule lookup tool, as rates update each January 1.

For the RVU breakdown by work, practice expense, and malpractice, the FastRVU 2026 lookup tool shows current MPFS values without a CMS data file download.

Commercial payer rates for 94070 vary widely. Some contracts pay at or above Medicare, while others discount the Medicare rate or use a separate fee schedule. Pabau, the practice management platform we build, submits US claims through Claim.MD, a clearinghouse that connects to thousands of US payers. Eligibility checks with supported payers let staff confirm coverage before the patient arrives for the challenge test.

Split billing applies when different entities perform the technical and professional components. In that scenario:

• The hospital or facility bills the technical component using modifier TC.
• The physician group bills the professional component (interpretation) using modifier 26.
• Neither party should bill the global code (without a modifier) when split billing applies.

Accurate revenue cycle management for split-billed pulmonary function tests depends on the facility billing team and the physician practice agreeing who bills which component. When that agreement breaks down, the same test gets billed twice or not at all.

Prior authorization requirements for CPT 94070

Medicare does not require prior authorization for CPT code 94070. Medicare Advantage plans and commercial managed-care payers often do, as part of utilization management for diagnostic pulmonary tests.

When a commercial payer requires authorization, the request typically includes:

• The treating physician’s referral note
• The working diagnosis with supporting history
• Prior spirometry results showing normal or borderline baseline lung function
• A statement of medical necessity explaining why a challenge test is needed rather than empiric asthma treatment

Thorough insurance eligibility verification at scheduling should include a check of whether the plan requires authorization for PFT codes.

A missing or expired authorization is a common reason 94070 claims are denied. Track each authorization’s expiry date against the test date, especially when the test is booked more than two weeks after the authorization was issued.

Top reasons CPT 94070 claims are denied

Denial patterns for 94070 are consistent enough to catch most of them before submission. The leading causes, based on NCCI edit policy and payer LCD criteria, are:

1. Unbundling 94010 with 94070. Billing CPT 94010 (simple spirometry) separately on the same date as 94070 violates NCCI edits. The serial spirometry is already paid within 94070. The 94010 line is denied, and the claim may be flagged for audit.
2. Missing serial measurement documentation. A record showing only a single post-challenge FEV1 value does not satisfy the “multiple spirometric determinations” descriptor. Payers request records and deny when only one measurement interval is documented.
3. Physician supervision not documented. The record must show the supervision level that the MPFS supervision indicator and your MAC’s policy require. Verify the current indicator, because a co-signature added days later may not meet it.
4. ICD-10 code not on the payer’s covered diagnosis list. Some commercial payers require a J45 asthma code as the primary diagnosis for 94070. With those payers, R05.9 (cough) as the sole diagnosis results in a medical necessity denial.
5. Missing or expired prior authorization. Commercial managed-care and Medicare Advantage plans that require authorization deny claims submitted without a valid auth number.
6. Missing signed physician interpretation. Some practices submit the technician report without a separate physician interpretation note. Payers expect a signed interpretation whenever the professional component is billed.

Pabau’s claims management software keeps the claim, its authorization and its remittance in one record, so these checks happen before submission. For structured denial management workflows, track 94070 denial reasons monthly and build payer-specific pre-submission checks for the top three.

How to bill CPT 94070 correctly: Step-by-step workflow

A systematic billing workflow for 94070 prevents the most predictable denials. Use these steps in sequence.

1. Verify eligibility and authorization before scheduling. Confirm the patient’s plan covers bronchospasm provocation testing and whether prior authorization is required. Obtain the auth number and log the expiration date.
2. Confirm the clinical indication and ICD-10 code. The ordering physician’s referral should specify a diagnosis code on the payer’s covered list. Cross-check against the applicable MAC LCD before the visit.
3. Document the protocol in full during the procedure. The technician must record the provoking agent, dose or concentration, and FEV1/FVC values at each measurement interval. A printed spirometry trace with timestamps at each interval satisfies most audit requests.
4. Physician signs the interpretation the same day. The signed interpretation note should reference the serial measurement results and state the physician’s clinical conclusion. Backdated interpretations are a red flag in audits.
5. Determine global vs split billing. If the physician group owns the equipment and supervises the test in its own office, bill 94070 globally with no modifier. If a hospital outpatient department performs the test, the facility bills TC and the physician group bills modifier 26.
6. Add the agent administration line. Report 95070 or 95071 for administering the challenge agent, matching the agent documented in the protocol.
7. Select the correct place-of-service code. POS 11 (office) for the non-facility rate; POS 22 (hospital outpatient) for the facility rate. Mismatched POS codes are a common source of payment-rate errors.
8. Check bundling and submit through a clearinghouse. Remove any 94010 line on the same date before submission. Pabau sends the claim as a CMS-1500/837P file through Claim.MD, and the remittance returns as an ERA.
9. Work denials within 30 days. For 94070 denials, read the claim adjustment and remittance remark codes (CARC/RARC) on the remittance. Most denials are correctable with an appeal letter that includes the full serial measurement log and the physician supervision note. See common denial codes for CARC-to-cause mapping.

How claims management software reduces CPT 94070 denials

Many pulmonology practices assemble a 94070 claim from a spirometry printout, a separate authorization log and a clearinghouse portal. Each hand-off is a chance to lose the auth number or send the claim before the interpretation is signed.

In Pabau, the authorization sits on the patient’s case with its dates and sessions, and staff see a warning when one is missing. Claims go out as CMS-1500/837P files through Claim.MD, after an eligibility check with supported payers.

ERA remittances post back against each claim, so a denied or underpaid 94070 line surfaces without a manual portal check. The result is fewer claims returned for a missing authorization, and faster appeals for the ones that are.

Submit cleaner CPT 94070 claims

Pabau sends CMS-1500/837P claims through Claim.MD, runs eligibility checks with supported payers, and posts ERA remittances. Your team spends less time on 94070 rework.

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Conclusion

Treat 94070 as one line in a small claim set, not a standalone code. The serial spirometry, the agent administration and any split interpretation each need their own decision before submission.

The trade-off worth remembering is time at the front end against rework at the back. Five minutes confirming the authorization, the interval log and the signed interpretation costs less than one appeal. Practices that build those checks into scheduling and sign-off send clean claims the first time.

Book a demo to see how Pabau tracks authorizations and sends pulmonary function test claims through Claim.MD.

Continue your research

Need to understand how clearinghouses process your PFT claims? Claim.MD clearinghouse guide explains how electronic claim routing, edits, and ERA processing work for outpatient diagnostic billing.

Confused by denial remark codes on your 94070 remittances? Electronic remittance advice explained breaks down how to read ERA files and map CARC/RARC codes to actionable fixes.

Looking for a framework to systematically reduce your claim rejection rate? Medical billing compliance guide covers documentation standards, audit triggers, and payer policy alignment for diagnostic procedure codes.

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