CMS’s claims attachments rule sets deadline to shift to full electronic submission

New administrative standards from CMS give providers two years to prepare to submit all claims-related documentation electronically.

The agency issued a final rule to create the first HIPAA-adopted national standards for the electronic exchange of supporting clinical documentation. A primary goal of the new regulations is to phase out manual processes among both providers and payers. A benefit for taxpayers will be an estimated $781 million in annual savings on healthcare spending, CMS said.

“Despite the healthcare industry’s widespread use of electronic health records (EHRs) and broad implementation of the Health Insurance Portability and Accountability Act of 1996 (HIPAA) transaction standards, the exchange of healthcare claims attachments has remained largely manual, frequently relying on fax, mail or portal uploads,” CMS wrote in the rule.

When the compliance deadlines arrive in May 2028, providers will be prohibited from sending paper-based submissions to payers for attachments such as medical records, clinical notes, imaging, lab results and telehealth visit documentation.

Much work lies ahead over the next two years to meet the requirements of the new rule, as indicated by the latest data from CAQH. Between 2023 and 2025, adoption by medical plans of fully electronic administrative transactions improved or remained stable in most transaction categories (including 98% for claims submission) but fell from 29% to 24% for attachments.

“Adopting standards for healthcare claims attachments will yield numerous benefits, including reducing administrative burden and costs, removing the need for proprietary data programs, cutting lengthy processing times and eliminating the risk of lost paper documents,” the final rule states.

“The futuristic medical breakthroughs we’ve achieved, like augmented reality glasses that give surgeons X-ray vision, shouldn’t have to coexist with administrative systems that often lag decades behind,” Mehmet Oz, MD, administrator of CMS, said in a news release.

Financial implications for hospitals and clinicians

CMS estimated that roughly 80% of savings accruing to healthcare providers through the rule would go to clinicians and 20% to hospitals. For hospitals, that amounts to $130 million per year.

“We believe the majority of healthcare claims attachments transactions will come from clinician practices, since plans and hospitals generally have other payment requirements for more expensive inpatient admissions and outpatient procedures, such that claims attachments would be required less frequently,” CMS states in the rule.

CMS anticipates faster claims adjudication, fewer follow-up requests and reduced staff burden but acknowledges that preparation will have to include staff training on new workflows and coordination with EHR vendors and clearinghouses.

Estimated costs to prepare for the 2028 deadline among hospitals fall within a range of $1.4 billion to $2.84 billion, although an uncertain portion of that would be borne by health IT vendors. CMS’s ballpark projection allocates 60% of the costs to vendors and the remainder to customers.

Required standards and technical infrastructure

Providers will need to support HIPAA-adopted standards for claims attachments, including specified X12 transactions for transmitting “additional information to support a healthcare claim or encounter” (X12N 275) and for responding to a payer’s “claim request for additional information” (X12N 277).

HL7 clinical documentation standards for packaging clinical data include Consolidated Clinical Document Architecture and the 2022 version of the Attachments Implementation Guide. The latter is a change from a CMS proposal that the 2017 guide would apply. Updates in the 2022 version “better facilitate” widespread implementation of the X12 standards, according to the new rule.

Providers also will face electronic signature requirements for authenticating claims attachment submissions. Manual attestations or informal sign-offs will be deemed noncompliant.

A point of emphasis in the rule is that the signatures do not impose new clinical documentation mandates. Electronic test orders will not require an electronic signature unless obligated by a different rule or statute.

“Pursuant to the requirements of this final rule, an electronic signature is required only on the attachment package being transmitted and only when a health plan requires an electronic signature,” CMS wrote.

Alignment with prior authorization regulations

In a significant change from the proposed rule issued by the Biden administration in late 2022, the new requirements apply only to claims attachments and not to prior authorization. CMS acknowledged concerns about conflicts between the proposals regarding prior authorization and existing transmission standards, along with potential misalignment with 2024 regulations on interoperability and prior authorization.

The agency intends to evaluate prior authorization standards and possibly revisit the issue in a later rule. For now, standardization is being framed specifically as a solution for claims-related processes rather than for interoperability.

Prior authorization already is being addressed in some respects, including via the 2024 regulations, some of which took effect at the start of 2026. Health plans in Medicare Advantage, Medicaid managed care and the Affordable Care Act marketplaces now must have the capability to receive and process prior authorization requests electronically. At the start of 2027, specified application programming interfaces (APIs) that support data exchange for prior authorization and other processes must be in place.

Other provisions in that rule require decisions on prior authorization within 72 hours for urgent requests and seven days for standard requests as of 2026. In addition, denials must include a specific reason that references plan rules and coverage criteria.

Payer commitments to reduce administrative burden

CMS also has initiatives underway to reduce the burden of prior authorization among commercial health plans, including an announced commitment by payers representing more than 85% of covered lives nationally. In June 2025, those payers pledged “to reduce the volume of codes requiring prior authorization, to shorten the time frame and increase the transparency, to eliminate or make invisible the opacity of that process for providers and patients alike,” Chris Klomp, director of CMS’s Center for Medicare, said in February at the agency’s Burden Reduction Conference.

Among codes that will remain subject to prior authorization as of 2027, the payers said at least 80% “would be adjudicated in real time in the physician’s office while the patient was still there,” Klomp said.