What CPT/HCPCS codes are used for 24-hour cardiac monitor billing in 2025?
Executive summary
The primary CPT codes used in 2025 for 24‑hour external cardiac monitoring include the Holter set (most commonly 93224 for the physician review of 24‑hour ambulatory ECG) and mobile cardiac telemetry sets (93228 and 93229 for professional and technical components of wearable telemetry/services), with related event‑monitor codes (e.g., 93268/93272) and a broader family of monitoring codes that payers reference for coverage and payment [1] [2] [3] [4]. Medicare LCDs and contractor guidance stress documentation, set‑billing rules, and that some modifiers (TC/26) are not to be used with these monitoring codes, so local payer rules must be checked before final claim submission [5] [2] [6].
1. Which CPT codes describe a 24‑hour Holter and similar short ambulatory monitoring
For a conventional 24‑hour Holter, payers and coding resources commonly point to the CPT codes in the 9322x series — notably CPT 93224 for the physician’s interpretation of 24‑hour ambulatory ECG studies — and related codes in that block for technical components, summary reports, and longer durations as specified in CPT guidance [1] [5]. Coding manuals and Medicare articles emphasize that the submitted CPT/HCPCS code must accurately describe the service performed and that the medical record must justify the selected diagnosis and the need for monitoring beyond 24 hours if applicable [5].
2. Mobile cardiac telemetry (wearable, attended surveillance) — 93228 and 93229
Wearable external mobile cardiac telemetry is described in CPT 93228 (professional component: review/interpretation and 24‑hour availability/response) and CPT 93229 (technical component: patient hook‑up, instruction, supplies, daily reports and summary for up to 30 days) — language reflected in CMS guidance and contractor LCDs that define these codes as covering wearable telemetry services up to 30 days with attended surveillance and daily reporting [2] [3]. CMS guidance also explicitly warns not to append TC or 26 modifiers to codes 93224–93229 and related telemetry codes, a frequent source of billing error [2].
3. Event monitors and 24‑hour attended monitoring (93268, 93272 and cousins)
Event recorder codes such as 93268 and 93272 cover external event monitoring with auto‑activated or symptom‑activated memory loops and remote download capability for up to 30 days and are specifically called out by payers for services described as “24‑hour attended monitoring” when continuous surveillance is provided; some contractors and health plans list these as options depending on device capability and duration [3] [7]. Industry coding guides and device vendors present tables of possible CPT/HCPCS permutations for external cardiac monitoring, underscoring that the device technology (continuous Holter vs. telemetry vs. event recorder) drives code selection [4] [8].
4. Billing mechanics, payer rules, and evolving code sets in 2025
Medicare contractors require that monitoring codes be billed in sets and not completed within 29 days of each other for the same patient, and they reiterate that documentation must support medical necessity and the exact type and duration of monitoring performed [6] [5]. The coding landscape also showed activity for 2025: specialty societies reported new Category III/CPT-related entries for extended external ECG monitoring and other cardiac remote technologies (e.g., codes for 15–30 day external ECG monitoring and new HCPCS entries), signaling that practices should watch payer updates and CPT/HCPCS releases for substitutions or new reporting pathways [9].
5. Practical tension: vendors, payers, and the need to verify locally
Device manufacturers and vendor coding guides list possible CPT/HCPCS codes but also caution that payer interpretation varies; commercial vendors have incentives to position their devices to match higher‑reimbursing codes, while Medicare LCDs and carrier-specific billing rules ultimately govern acceptability — therefore reliance on manufacturer tables alone is risky without checking local LCDs and Medicare contractor guidance [4] [2] [6]. In sum, the 9322x family (including 93224 for 24‑hour Holter) and the mobile telemetry/event codes (93228/93229, 93268/93272) are the core codes used in 2025, but exact billing depends on device capability, service components, documentation and the payer’s LCD or policy [1] [2] [3] [5].