---
title: "POST /api/eligibility/cob/v1"
method: POST
path: "/api/eligibility/cob/v1"
---

# POST /api/eligibility/cob/v1

`POST /api/eligibility/cob/v1`

## Request

- Base URL: `https://forecaster.cairhealth.com`
- URL: `https://forecaster.cairhealth.com/api/eligibility/cob/v1`
- Auth: HTTP bearer

Provides coordination of benefits (COB) information for a patient, including primary and secondary insurance details.

## Request body

- object
  - `patientFirstName` string, required: Patient first name
  - `patientLastName` string, required: Patient last name
  - `patientDOB` string: Patient Date of Birth, formatted as MM-DD-YYYY
  - `patientMemberId` string: Member ID of patient's insurance policy. For a successful check, you MUST provide either the member ID or the SSN.
  - `patientSSN` string: Patient's Social Security Number. For a successful check, you MUST provide either the member ID or the SSN.
  - `dateOfCoverage` string, required: Date to request coverage information. Formatted as MM-DD-YYYY
  - `payerId` string, required: Payer ID. Accepts either the Stedi Payer ID (e.g. 'KMQTZ', 'HGJLR') or the Primary Payer ID (e.g. '87726') from the platform or the [Fetch Enrollments](../enrollments/fetch-enrollments) API
  - `providerId` string, required: Billing Provider ID. Accepts either the CAIR logical provider ID (from /admin/provider/<id>) or the clearinghouse provider ID from the [Fetch Enrollments](../enrollments/fetch-enrollments) API
  - `dependentFirstName` string: Dependent's first name if checking coverage for a dependent
  - `dependentLastName` string: Dependent's last name if checking coverage for a dependent
  - `dependentDOB` string: Dependent's Date of Birth, formatted as MM-DD-YYYY
  - `serviceTypeCodes` string[]: Service type codes to request coverage information for

## Response `200`

COB check successful

- object
  - `cobCode` string: Code indicating the type of coordination of benefits
  - `requestedPlanBenefits` object[]: Information about the requested plan benefits
    - `payerName` string: Name of the payer
    - `serviceTypeCodes` object[]: Service type codes and their descriptions
      - `code` string: Service type code
      - `name` string: Description of the service type
    - `benefitDate` object
      - `planStartDate` string: Start date of the plan
  - `additionalPlanBenefitInfo` object[]: Additional information about plan benefits
    - `payerName` string: Name of the payer
    - `payerPrimacy` string: Indicates if this is the primary or secondary payer
    - `serviceTypeCodes` object[]: Service type codes and their descriptions
      - `code` string: Service type code
      - `name` string: Description of the service type
    - `benefitDate` object
      - `overlapBeginDate` string: Start date of benefit overlap
      - `overlapEndDate` string: End date of benefit overlap
      - `planStartDate` string: Start date of the plan
      - `planEndDate` string: End date of the plan
      - `coordinationOfBenefits` string: Coordination of benefits date
    - `subscriber` object
      - `firstName` string: Subscriber's first name
      - `lastName` string: Subscriber's last name
      - `dateOfBirth` string: Subscriber's date of birth
      - `memberId` string: Subscriber's member ID

## Other responses

- `400`: Invalid request body or validation error
- `401`: Unauthorized access or invalid organization ID
- `500`: Server error or provider/payer enrollment issue

## Changes

- **2026-11-03** `b32380ccde9a`: 3 info
  - added the optional property `error` to the response with the `400` status
  - added the optional property `error` to the response with the `401` status
  - added the optional property `error` to the response with the `500` status

[Operation history](https://skmtc.dev/cairhealth/apis/cair-health-apis/changes/api/eligibility/cob/v1/post.md)

---

[API](https://skmtc.dev/cairhealth/apis/cair-health-apis.md) - [All operations](https://skmtc.dev/cairhealth/apis/cair-health-apis/llms.txt) - [OpenAPI document](https://skmtc.dev/cairhealth/apis/cair-health-apis/revisions/b32380ccde9a?raw)