A practice bills an E/M visit on the same day as a minor procedure. The claim is paid without modifier 25, even though the E/M service may have been significant and separately identifiable. That type of billing pattern is specifically part of OIG’s 2026 work plan. If the documentation doesn’t support a significant and separately identifiable E/M service, the claim may present a compliance risk. OIG’s 2026 work plan specifically includes a review of E/M services performed on the same day as minor surgery when modifier 25 was not appended.
That’s one example of the type of billing issue reflected in OIG’s 2026 work plan. It’s rarely about obscure or unusual billing. It’s about a handful of specific, well-known risk areas where OIG has explicitly said it’s looking and where the gap between what a provider believes is defensible and what the documentation actually proves tends to be widest.
Why Is Modifier 25 an OIG Medical Billing Audit Risk in 2026?
In March 2026, OIG announced a work plan project examining E/M services performed on the same day as minor surgery when modifier 25 was not appended. OIG said it would determine whether Medicare Administrative Contractors’ processing and payment of those claims complied with Medicare requirements. Modifier 25 has also been the subject of previous OIG reviews. OIG’s earlier work found significant compliance problems in certain E/M claims billed with modifier 25, including claims for E/M services provided on the same day as intravitreal injections. When modifier 25 is reported, the medical record must support a significant, separately identifiable E/M service performed on the same day as the procedure.
Chronic Care Management Billing Is Under Direct Review
Medicare has paid for chronic care management (CCM) services since 2015, and utilization grew substantially through the following years. That increase is part of the context for OIG’s 2026 review. In March 2026, OIG announced a review of Medicare Part B CCM payments that may not comply with the requirement that patients have two or more qualifying chronic conditions. The conditions must be expected to last at least 12 months, or until the patient’s death, and must place the patient at significant risk of death, acute exacerbation or decompensation, or functional decline. Practices billing CCM codes need documentation that clearly establishes both qualifying conditions, the required monthly non-face-to-face time, and a documented care plan. Billing CCM based on a general sense that a patient is medically complex, without the specific qualifying conditions and time clearly logged, is precisely the pattern this review is designed to catch.
Why Does Medicare Advantage Diagnosis Coding Keep Drawing Scrutiny?
OIG continues to scrutinize diagnosis codes submitted for Medicare Advantage risk adjustment, particularly diagnoses that aren’t clearly supported by current documentation. In a 2026 audit of Priority Health, OIG found that medical records did not support the diagnosis codes for 252 of 300 sampled enrollee-years, resulting in $828,010 in net overpayments. Based on those sample results, OIG estimated that Priority Health received at least $4.4 million in net overpayments for 2018 and 2019.
Medicare Advantage organizations submit diagnosis codes to CMS for risk adjustment, and those diagnoses must be supported by the medical records. Providers therefore play an important role by documenting the conditions evaluated and managed during the encounter rather than simply carrying unsupported diagnoses forward. A diagnosis carried forward without supporting documentation from the current service year can create significant compliance risk, and this remains one of the more active areas of federal review heading into the back half of 2026.
Predictive Data Analytics Are Changing How Audits Get Triggered
Claims data and other analytics can help federal agencies and Medicare contractors identify unusual billing patterns for further review. For providers, that makes internal monitoring of coding and utilization patterns an important part of compliance.
The Overpayment Obligation Doesn’t Disappear After the Audit
When a Medicare overpayment is identified, providers and suppliers generally have an obligation to investigate, report, and return it. For Medicare Parts A and B, CMS requires self-identified overpayments to be reported and returned by the later of 60 days after identification or the applicable cost-report due date, subject to applicable rules and exceptions. Detected but uncorrected billing issues carry more risk than an honest, promptly corrected mistake. Compliance programs that lack a clear, documented process for identifying and returning overpayments are themselves a compliance gap OIG has flagged as a concern.
A Quick Preparation Checklist
| Risk Area | What to Confirm |
| E/M + minor procedure claims | Documentation supports whether a separately identifiable E/M service was performed, and modifier 25 is reported when applicable |
| CCM billing | Two or more qualifying chronic conditions, monthly time, and a care plan are all documented |
| MA diagnosis coding | Submitted diagnoses are supported by the medical record and meet applicable risk-adjustment requirements |
| Billing pattern review | Internal audits compare billing volume and code selection against specialty norms |
| Overpayment handling | A documented process exists for identifying, investigating, and returning overpayments within required timeframes |
The Real Question Every Practice Should Ask
OIG’s 2026 work plan gives providers and healthcare organizations a clearer picture of several billing and documentation risks receiving federal scrutiny: a modifier with a long audit history, a care management code tied to a strict eligibility requirement, and Medicare Advantage risk-adjustment diagnoses under continued federal scrutiny. For healthcare providers, the practical takeaway isn’t to predict every future audit. It’s to understand the documentation and billing requirements behind the areas OIG is reviewing and strengthen internal controls accordingly.
Rapid RCM Solutions supports healthcare organizations by enhancing billing oversight by providing coding, charge entry, and reporting assistance, allowing them to detect any documentation and coding concerns before the claim is made. For more information on Rapid RCM Solutions’ medical billing support approach, check out rapidrcmsolutions.com.
