Essential Claim Fields | Medicare Billing: CMS-1500 & 837P

Use these slides to understand how to fill out key form fields for billing, diagnosis, service dates, place of service, and procedure codes.

Loop 2400 PS102 / Item 20

Required when billing for diagnostic tests subject to the anti-markup payment limitation.

Table 37: Loop 2400 PS102 / Item 20 Fields
Outside Lab?	Source
Check Yes or No when billing for diagnostic tests subject to the anti-markup payment limitation.	Health care professional or supplier’s records

Yes means that the physician or other supplier who performed the test doesn't share a practice with the physician or other supplier billing for the service
No means the claim doesn’t include diagnostic tests subject to the anti-markup limitation

When you check Yes:

Enter the acquisition price under charges
Complete item 32 Service Facility Location Information

When billing for multiple tests subject to the anti-markup limitation, submit each test on a separate CMS-1500. You can submit multiple anti-markup tests on the 837P if you submit the correct line level information when different service facility locations provide services.

Loop 2300 HI01-HI12 / Item 21

Table 38: Loop 2300 HI01-HI12 / Item 21 Fields
Diagnosis or Nature of Illness or Injury ICD Indicator	Source
Enter the patient’s diagnosis or condition. Physician and non-physician specialties like PA, NP, CNS, and CRNA use diagnosis codes to the highest level of specificity for the date of service. Ambulance suppliers, provider specialty type 59, are the exception. Enter the diagnosis in priority order. Submit all narrative diagnoses for non-physician specialties on an attachment.	ICD-10-CM diagnosis code

Review the Diagnosis Coding: Using the ICD-10-CM web-based training (WBT) course for ICD-10-CM/PCS guidance.

Loop 2400 DTP / Item 24A

Table 39: Loop 2400 DTP / Item 24A Fields
Dates of Service	Source
Enter a 6-digit (MMDDYY) or an 8-digit (MMDDCCYY) date for each procedure, service, or supply. When you show From and To dates for a series of the same services, enter the number of days or units in column G. MACs will return the claim as unprocessable if a date of service extends more than 1 day and a valid To date isn’t shown.	Patient records

Loop 2300 CLM05-1 or 2400 SV105 / Item 24B

Table 40: Loop 2300 CLM05-1 or 2400 SV105 / Item 24B Fields
Place of Service	Source
Enter the appropriate Place of Service (POS) codes. Using POS codes, name the setting for each item used or service performed.	National POS Code Set, Medicare Claims Processing Manual, Chapter 26

For all services paid under the Physician Fee Schedule (PFS), use the POS code assigned to the setting where the patient got face-to-face service.

When a service is provided to a patient who’s a registered inpatient or an outpatient of a hospital, use:

Inpatient hospital POS code 21
Off Campus-Outpatient Hospital POS code 19
On Campus-Outpatient Hospital POS code 22

Loop 2400 SV101-2 / Item 24D

Table 41: Loop 2400 SV101-2 / Item 24D Fields
Procedures, Services, or Supplies	Source
Enter the procedures, services, or supplies using CMS HCPCS codes. When it applies, show HCPCS code modifiers with the HCPCS code. You can add up to 4 modifiers to the CMS-1500.	Level I: American Medical Association (AMA) maintains the CPT codes Level II: CMS maintains the HCPCS codes

Enter the specific procedure code without a narrative description. But when reporting an unlisted procedure code or a Not Otherwise Classified (NOC) code, include a clear description narrative in item 19 (2400 SV101-7). Otherwise, submit an attachment with the claim.

When you submit NOC codes without a clear description narrative or without mentioning that a clarifying attachment is following, the MAC will return the claim as unprocessable.