CMS 1500 Claim Form Reference

The CMS 1500 form is the standard form used by healthcare providers to submit claims to insurance companies for reimbursement. Most of what is described below is available in NUCC’s 1500 Health Insurance Claim Form Reference Instruction Manual, but we’ve attempted to make it a bit more digestible and relevant to analytics (vs claims submission). While most claims are now submitted electronically, it is easier to understand the dataset when viewed through the lens of the traditional paper form.

Insured Information

These fields provide information about the insured party (and the patient, if the patient is the insured party). We’ll refer to the “insured party” as the “member” going forward.

Field 1 and 1a provide the type of health insurance coverage and the member's identification number, if available. Typically, the vast majority of claims will be Medicare, Medicaid, or Group Health Plan. Tricare and CHAMPVA are military health insurance programs. Black Lung is a federal program that provides coverage for miners with black lung disease. Other is a catch-all for other types of insurance.

Field 4 is the member's name, field 7 is the member's address, and field 11 is the policy group (the group number on your insurance card).

Field 11.a is the member's date of birth, 11.c is the insurance plan name, and 11.d is whether the member has other health insurance coverage (typically a Medicare supplement plan).

Patient Information

Field 2 is the patient's name, field 3 is the patient's date of birth and sex, and field 5 is the patient's address. Field 6 is the patient's relationship to the insured member.

Cause of Injury

This section is relatively straightforward, and identifies the setting of the accident which might determine ultimate responsibility for payment (worker’s compensation for an injury related to employment, or another driver's insurance in the case of an automobile accident). Field 10.a is whether the injury was related to employment, field 10.b is whether the injury was related to an automobile accident, and if so what state it took place in, and field 10.c is the catch-all "other accident" category.

Other Insurance

If field 11.d ("Is there another health benefit plan?") was answered in the affirmative, then this section is used to provide information about that plan. Field 9 is the supplemental plan's member name, and fields 9.a and 9.d are the supplemental plan's group number, and plan name, respectively.

Signatures

Fields 12 and 13 are signatures from the patient and insured member (we certainly don't receive these on the electronic version)!

Encounter Level Information

Now that we’re past the who is the patient and who is going to pay for it questions, we get into the meat of the claim. This section describes “header” level information, such as referrals and various dates associated with the claim.

Field 14 describes the first date of the current illness. NOT the date of service, but the day reported by the patient as the start of the illness.

Field 15 is an opportunity to document some other date related to the illness, and has a qualifier associated with it.

Applicable qualifiers are reproduced below for convenience:

* 454 - Initial Treatment
* 304 - Latest Visit or Consultation
* 453 - Acute Manifestation of a Chronic Condition
* 439 - Accident
* 455 - Last X-ray
* 471 - Prescription
* 090 - Report Start (Assumed Care Date)
* 091 - Report End (Relinquished Care Date)
* 444 - First Visit or Consultation

Field 16 is filled in if the patient is employed and unable to work in their current condition. If this is filled in, it is usually indicative of a worker's compensation claim.

Field 17 is where we find referring provider information. There is a qualifier associated with this field:

* DN - Referring Provider
* DK - Ordering Provider
* DQ - Supervising Provider

Field 17.a is reserved for an "other" identifier, with a qualifier to describe what that identifier is:

* 0B - State License Number
* 1G - Provider UPIN Number
* G2 - Provider Commercial Number
* LU - Location Number (This qualifier is used for Supervising Provider only.)

Field 17.b is the NPI of the provider specified in field 17.

Field 18 is the hospitalization date range, if applicable. These dates are also referred to as the "admit and discharge" dates, and their presence indicates that the claim is for an inpatient stay.

Diagnosis Information

Field 19 is for "additional claim information". There is a long section in the NUCC manual about what information could show up in this field, and it can be somewhat tantalizing to think about the possibilities. In practice, this field is rarely used.

Field 20 is filled out if services were provided by an entity other than the billing provider. If Yes is selected, the charge section must be filled in as well.

Field 21 is the diagnosis list. You specify the ICD version either 9 or 10 in the ICD Ind. section. This is a list of up to 12 diagnosis codes; interestingly enough, there is no guidance from NUCC as to the order of the codes in this list. In practice, the first code is usually the primary diagnosis, and the rest are secondary diagnoses, and this order can affect the level of reimbursement for the claim.

Field 22 is for resubmitted claims. The resubmission code should be either 7 - Replacement of prior claim or 8 - Void/cancel of prior claim. The original claim number should be provided in the Original Ref. No. field.

Field 23 is for prior authorization numbers, if the payer has already authorized the procedures being performed.

Procedure Level Information

Finally, we have the meat of the claim. Field 24 collects dates of service, place of service, procedure codes, charges, and rendering provider information.
Let's look at each part in detail.

Field 24.a is the date(s) of service. Often a single date, but can be a range of dates.

Field 24.b contains the place of service code set, which is a list of 2-digit codes that describe the setting in which the service was performed. The full list of codes is available here.

Field 24.c identifies if the procedure was an "emergency". The definition of "emergency" can differ by payer contract or state and federal regulation.

Field 24.d is for the procedure code and any corresponding modifiers.

Field 24.e is the diagnosis pointer for the procedure listed in 24.d. It relates the procedure performed to one or more diagnoses listed in field 21.

Field 24.f is the charge for the procedure listed in 24.d. Remember this is the charge amount, not the reimbursed amount. The charge amount, frankly, is often so different from the reimbursed amount as to be almost meaningless.

Field 24.g is the number of days or units for the procedure listed in 24.d. If it is days being listed, the number of days should match the date range in field 24.a.

Field 24.h is utilized if there is a requirement to report the service as part of a family planning service; otherwise, it is left blank.

Field 24.i is a qualifier for field 24.j, which is a rendering provider identifier. The qualifier can be one of the following:

* 0B - State License Number
* 1G - Provider UPIN Number
* G2 - Provider Commercial Number
* LU - Location Number
* ZZ - Provider Taxonomy

Field 24.j also contains the rendering provider's NPI.

Provider and Site of Service Information

Here we wrap up the claim with a few very important pieces of information.

Field 25 is the tax number of the billing provider, usually an EIN but sometimes an SSN for a sole proprietor.

Field 26 is the patient's account number with the billing provider. This is usually the patient's medical record number.

Field 27 is the acceptance of assignment indicator. This is a Y or N field that indicates if the provider accepts assignment for the claim. If Y is selected, the provider agrees to accept the payment from the payer as payment in full. If N is selected, the provider may bill the patient for any amount not paid by the payer.

Field 28 contains the sum of all charges from field 24.f.

Field 29 is the amount the patient has already paid for services described in field 24.

Fields 30 and 31 are reserved for NUCC use, and the provider signature, respectively.

Field 32 is a crucially important field - the site of service where services were rendered. The address where the procedures took place should be entered in field 32; if the Service Location NPI is different from the Billing Provider NPI, then the Service Location NPI should be entered in field 32.a. Field 32.b provides an opportunity for another, non-NPI identifier for the service location.

Field 33 collects the billing provider's address; similar to field 32, 33.a holds the billing provider's NPI, and 33.b is for an additional identifier.

Summary

The CMS 1500 form is complex, and it’s easy to see how errors can be made during submission! However, it contains a wealth of data that can be used for an endless variety of analyses. Please take a look at our article on using claims data for more insight.