Understanding CMS 1500 Box 19 guidelines is crucial for accurate medical billing. This field, titled “Reserved for Local Use,” serves as a versatile space on the CMS 1500 claim form for additional information not accommodated elsewhere. Its “local use” designation means it can be used differently by various payers (like Medicare Administrative Contractors or private insurers) to convey specific details essential for claim processing. Mastering how to fill Box 19 CMS 1500 correctly can prevent delays and denials, making it a critical component for many unique billing scenarios. This comprehensive guide will walk you through the various critical scenarios for using the CMS-1500 local use field effectively.

Specific Scenarios for CMS 1500 Box 19 Data Entry

Routine Foot Care Claims

When a physician submits claims for routine foot care, Box 19 requires the date the patient was last seen. This date should be entered in either a 6-digit (MMDDYY) or an 8-digit (MMDDCCYY) format. Additionally, you must include the National Provider Identifier (NPI) of the attending physician. The NPI universally replaced the legacy Unique Physician Identification Number (UPIN) for all identifiers submitted on the CMS-1500 form, effective May 23, 2008. Proper entry here is vital for CMS 1500 Box 19 guidelines relating to podiatric services.

Physical, Occupational, and Speech-Language Pathology Services

For physical therapy, occupational therapy, or speech-language pathology services with dates of service on or after June 6, 2005, the date last seen and the NPI of an ordering, referring, attending, or certifying physician or non-physician practitioner are generally not required in Box 19. If this information is submitted voluntarily, it must be accurate; otherwise, it could lead to claim rejection or denial. However, if the therapy service is provided “incident to” the services of a physician or non-physician practitioner, specific “incident to” policies still apply.

The “incident to” policy dictates that services must be an integral, although incidental, part of the physician’s professional service, commonly furnished in a physician’s office or clinic. This requires direct supervision by the physician or another healthcare professional acting within their scope of practice. For example, the ordering physician who provided the initial service would typically be identified in Item 17 and Item 17a, and the supervising physician or practitioner would be identified in Item 24J of the CMS 1500 form.

Chiropractor X-Ray Date

When billing for chiropractor services, if an X-ray (rather than a physical examination) was used to demonstrate subluxation, enter the X-ray date in Box 19. Use either a 6-digit (MMDDYY) or an 8-digit (MMDDCCYY) format. By entering this X-ray date and the initiation date for the course of chiropractic treatment in Item 14, the chiropractor certifies that all relevant information requirements, including the level of subluxation, are on file and available for carrier review. Refer to CMS Publication 100-02, Medicare Benefit Policy Manual, Chapter 15, for detailed guidelines on chiropractic services.

Not Otherwise Classified (NOC) Drugs and Unlisted Procedures

For “Not Otherwise Classified” (NOC) drugs, which are medications that do not have a specific HCPCS code, you must enter the drug’s name and dosage in Box 19. Similarly, when using an “unlisted procedure code” (a CPT code for a procedure without a specific existing code) or another NOC code, provide a concise description if it fits within the box’s character limits. If the description is too extensive, an attachment must be submitted with the claim. This is a common application of the CMS-1500 local use field for specialized billing.

Reporting Multiple Modifiers (-99)

When modifier -99 (indicating multiple modifiers) is entered in Item 24d of the CMS 1500 form, Box 19 is used to list all applicable modifiers. If modifier -99 appears on multiple line items within a single claim, you should specify the modifiers for each line item individually. The format is LineNumber=(Modifier1, Modifier2,...). For example, if line item ‘1’ has modifiers ‘RT’ and ‘LT’, you would enter: 1=(RT,LT). This level of detail is essential for accurate processing when using the how to fill Box 19 CMS 1500 for complex coding.

Homebound or Institutionalized Patient Services (Independent Laboratories)

For independent laboratories rendering EKG tracings or obtaining specimens from homebound or institutionalized patients, the statement “Homebound” must be entered in Box 19. This indicates that the service was provided to a patient confined to their home or residing in an institution. Detailed definitions of “homebound” and comprehensive information regarding medically necessary laboratory services for these patient types can be found in CMS Publication 100-02, Medicare Benefit Policy Manual, Chapter 15 (“Covered Medical and Other Health Services”), CMS Publication 100-04, Medicare Claims Processing Manual, Chapter 16 (“Laboratory Services From Independent Labs, Physicians and Providers”), and CMS Publication 100-01, Medicare General Information, Eligibility, and Entitlement Manual, Chapter 5 (“Definitions”).

Patient Refusal to Assign Benefits

If a beneficiary explicitly refuses to assign their benefits to a non-participating physician or supplier who typically accepts assignment on a claim, the statement “Patient refuses to assign benefits” must be entered in Box 19. In such scenarios, Medicare payment will be made directly to the beneficiary, not the provider.

Testing for Hearing Aids

For services related to testing hearing aids, particularly when seeking intentional denials from Medicare (e.g., when another payer is primary), enter the statement “Testing for hearing aid” in Box 19. This helps clarify the nature of the service for claim processing.

Dental Examinations Preceding Surgery

When billing for dental examinations that are directly related to and performed in preparation for a specific surgical procedure, you must enter the description of that specific surgery in Box 19. This ensures proper linkage between the dental exam and the medical necessity for the surgery.

Low Osmolar Contrast Material (When Not Coded Separately)

If low osmolar contrast material is billed and there isn’t a specific HCPCS code to cover it, then the specific name and dosage amount of the contrast material must be entered in Box 19. This provides necessary detail for payers.

Global Surgery Claims: Assumed and Relinquished Dates

“Global surgery” refers to a comprehensive package of services related to a surgical procedure, including pre-operative, intra-operative, and post-operative care. When providers share post-operative care for a global surgery claim, Box 19 is used to enter the 6-digit (MMDDYY) or 8-digit (MMDDCCYY) date when care was assumed by one provider or relinquished by another. This is crucial for coordinating billing among multiple providers involved in the patient’s surgical episode.

National Emphysema Treatment Trial (NETT) Claims

For all claims related to the National Emphysema Treatment Trial (NETT), the demonstration ID number “30” must be entered in Box 19. This identifies claims associated with this specific research trial.

Purchased Interpretation of Diagnostic Tests

When billing for a purchased interpretation of a diagnostic test, Box 19 requires the National Provider Identifier (NPI) of the physician performing that interpretation. This ensures proper attribution and payment for the professional component of the service. For additional information, refer to CMS Publication 100-04, Medicare Claims Processing Manual, Chapter 1, Section 30.2.9.1.

Anemia Management: ESRD Beneficiaries and Cancer Treatment

For Method II suppliers billing for injections of Aranesp for End-Stage Renal Disease (ESRD) beneficiaries on dialysis, the most current hematocrit (HCT) value must be entered in Box 19. ESRD beneficiaries are individuals with permanent kidney failure requiring dialysis or transplantation.

Similarly, for individuals and entities billing Medicare Administrative Contractors (A/B MACs) for administrations of Erythropoiesis Stimulating Agents (ESAs) or other Part B anti-anemia drugs (not self-administered) in cancer treatment, the most current hemoglobin or hematocrit test results are required. The test results should be entered using a specific format: “TR/” followed by “R1/” for hemoglobin or “R2/” for hematocrit, and then the numeric test result figure (up to three numbers and a decimal point [xx.x]).

Examples:

• For a hemoglobin test result of 9.0: TR/R1/9.0
• For a hematocrit test result of 27.0: TR/R2/27.0

For additional information on these guidelines, refer to CMS Publication 100-04, Medicare Claims Processing Manual, Chapter 8, Section 60.7.2.

Conclusion

The “Reserved for Local Use” field, Box 19 on the CMS 1500 form, is a critical element for conveying specific details necessary for proper claim adjudication. By diligently following these CMS 1500 Box 19 guidelines and understanding how to fill Box 19 CMS 1500 for each unique scenario, healthcare providers can significantly improve their claims processing efficiency and reduce denials. Always refer to the most current CMS manuals and payer-specific instructions for the most accurate and up-to-date requirements for this versatile field.