CMS 1500 claim form Box description and important fields explanation (2023)

Introduction: What is the CMS1500 form?

The CMS1500 form is a uniform billing form used by medical providers across the United States to submit claims for reimbursement from a government or private insurance carrier. It is recommended by most private health insurance companies, including Medicare. filling out the CMS1500 form is mandatory. There is always confusion in filling out the required fields. CMS 1500 form has 33 boxes in total. Missing the important fields may delay the payments. Below is the table of Guides to understand the field.

CMS 1500 form box explanation

The below table has a clear explanation on filling out the required field, Table starts from 1 – Type of insurance and ends with 33- Billing provider information. Missing to fill important fields would lead to denial.

Field Description Required
NA Carrier Block Y
BOX 1 Type of Insurance N
BOX 1A Insured’s ID Number (HIC) Y
BOX 2 Patient’s Name Y
BOX 3 Patient’s Birth Date, Sex Y
BOX 4 Insured’s Name N
BOX 5 Patient’s Address Y
BOX 6 Patient Relationship to Insured N
BOX 7 Insured’s Address N
BOX 8 Reserved for NUCC Use (previously Patient Status) DNU (DONT USE)
BOX 9 Other Insured’s Name N
BOX 9A Other Insured’s Policy or Group Number N
BOX 9B Reserved for NUCC Use (previously Other Insured’s Date of Birth, Sex) DNU (DONT USE)
BOX 9C Reserved for NUCC Use (previously Employer’s Name or School Name) DNU (DONT USE)
BOX 9D Insurance Plan Name or Program Name N
BOX 10A Is Patient’s Condition Related to Employment N
BOX 10B Is Patient’s Condition Related to Auto Accident N
BOX 10C Is Patient’s Condition Related to Other Accident N
BOX 10D Claim Codes (previously Reserved for Local Use) N
BOX 11 Insured’s Policy, Group, or FECA Number N
BOX 11A Insured’s Date of Birth, Sex N
BOX 11B Other Claim ID (previously Insured’s Employer Name or School Name) N
BOX 11C Insurance Plan Name or Program Name N
BOX 11D Is there another health benefit plan? N
BOX 12 Patient’s or Authorized Person’s Signature Y
BOX 13 Insured’s or Authorized Person’s Signature Situationally Required
BOX 14 Date of Current Illness, Injury, Pregnancy (LMP) N
BOX 15 Other Date (previously If Patient Has Had Same or Similar Illness) N
BOX 16 Dates Patient is Unable to Work in Current Occupation N
BOX 17 Name of Referring/Ordering ProviderQualifier
DN = Referring Provider DK = Ordering Provider DQ = Supervising Provider
Situationally Required
BOX 17A Other ID# N
BOX 17B Referring/Ordering NPI Situationally Required
BOX 18 Hospitalization Dates Related to Current Services Situationally Required
BOX 19 Additional Claim Information (previously Reserved for Local Use) N
BOX 20 Outside Lab Charges N
BOX 21 diagnosis or Nature of Illness or Injury Y
BOX 22 Resubmission and/or Original Reference Number Situationally Required
BOX 23 Prior Authorization Number or CLIA Number or Mammography Certification Number N
BOX 24
Section 24 Situationally Required
BOX 24A Date(s) of Service Y
BOX 24B Place of Service Y
BOX 24D Procedures, Services, or Supplies Y
BOX 24E Diagnosis Pointer Y
BOX 24F $ Total Charges (Billed Amount) Y
BOX 24G Days or Units Billed Y
BOX 24H EPSDT/Family Plan N
Shaded Line
ID Qualifier N
Shaded Line
ID Qualifier N
BOX 24J Rendering Provider ID # Situationally Required
BOX 25 Federal Tax ID or SSN Y
BOX 26 Patient’s Account Number N
BOX 27 Accept Assignment Situationally Required
BOX 28 Total Charge (Billed Amount) Y
BOX 29 Amount Paid (by Patient) N
BOX 30 Reserved for NUCC Use (previously Balance Due) DNU (DONT USE)
BOX 31 Signature of Physician or Supplier Including Degrees or Credentials Y
BOX 32 Service Facility Location Situationally Required
BOX 32A Service Facility NPI ( National Provider Identifier) N
BOX 32B Service Facility Other ID# N
BOX 33 Billing Provider Info and Phone # Y
BOX 33A Billing Provider NPI ( National Provider Identifier) Y
BOX 33B Billing Provider Other ID# N

CMS1500 images with required Fields

CMS 1500 form description and Box explanation

Who needs to fill out the form?

Due to complicated insurance coverage, many patients do not know or understand that they are required to fill out the CMS 1500 form for medical billing. As one of the only forms needed by all health care providers, this form can help ensure that patients are properly reimbursed. The CMS 1500 form helps establish a patient’s diagnosis, services rendered, and other important information to allow providers to bill for services. Strict requirements need to be followed in order for the CMS 1500 form to be processed correctly.


Every medical professional should know about the CMS1500 form. This form is used to report any money that has been exchanged hands between the health care provider and the patient. This form may also be referred to as a “UBAD” document, which stands for Uniform Billing and Accounting Document. The CMS1500 document is only necessary if your office accepts insurance payment or sends invoices to patients who are paying out of pocket.

Leave a Comment