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Centers for Medicare and Medicaid Services Enrollments API

Enrollment grouping validation and information.

Centers for Medicare and Medicaid Services Enrollments API is one of 41 APIs that Centers for Medicare and Medicaid Services publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Enrollments. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, authentication docs, and a GitHub repository.

This API exposes 1 operation across 1 path, and defines 12 schemas. It is described by OpenAPI 3.2.0, at version 1.

Requests are made against a single base URL, https://marketplace.api.healthcare.gov/api/v1.

1 operations 1 paths 12 schemas 1 POST

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
1
Base URL
https://marketplace.api.healthcare.gov/api/v1
Authentication
API Key
Resource Areas
1

Authentication & Security 1

Centers for Medicare and Medicaid Services Enrollments API declares 1 security scheme for authenticating requests. An API key is passed in the query as apikey (API_Key). By default, every request must be authenticated.

  • API_Key — Your API key should be included as a query parameter with the request. You can [fill out this form](https://cms.gov1.qualtrics.com/jfe/form/SV4N2GHCJfNuX7n8x)…

Paths & Operations 1

Across 1 path, the API surfaces 1 operation — 1 POST. Each is listed below with its method, path, parameters, and response codes.

Enrollments 1

Enrollment grouping validation and information.

POST
/enrollment/validate
Verify extended enrollment groups. The endpoint assumes an effective date of Jan 1 on enrollees ages unless effectiveage is provided on the enrollees. If iscustom is true, the endpoint will validate…
1 param body → 200400

Schemas 12

The contract defines 12 schemas that model the data the API accepts and returns. The most detailed are ExtendedEnrollee (13 properties), FlattenedEnrollmentGroup (8 properties), Address (6 properties), ExtendedEnrollment (6 properties). Each schema is shown below with its type and property counts.

MetalLevelEnum
string
Address
object
6 properties
PlanID
string
CostSharingReductionEnum
string
Cost-sharing reduction (CSR)
ExtendedEnrollee
object
13 properties
RelationshipEdge
object
3 properties
FlattenedEnrollmentGroup
object
8 properties
ExtendedEnrollment
object
6 properties
GenderEnum
string
Relationship
string
Should match one of the [listed valid relationships](introduction/more-information-about-households).
ProductDivisionEnum
string
CurrentEnrollment
object
Current/existing enrollment information used to determine tobacco status for CiC enrollments. This will ensure rate calculation is done correctly.
3 properties 3 required

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

cms-enrollments-api-openapi.yml Raw ↑

Other APIs Centers for Medicare and Medicaid Services publishes across the network.

CMS Data at the Point of Care (DPC) API
CMS Finder API
CMS Quality Payment Program (QPP) Submissions API
Centers for Medicare and Medicaid Services API Reference API
Centers for Medicare and Medicaid Services Bulk Data API
Centers for Medicare and Medicaid Services Code Search API
Centers for Medicare and Medicaid Services Cost Search API
Centers for Medicare and Medicaid Services Geography API
Centers for Medicare and Medicaid Services Households & Eligibility API
Centers for Medicare and Medicaid Services Insurance Issuers API
Centers for Medicare and Medicaid Services Insurance Plans API
Centers for Medicare and Medicaid Services Plans API
Where this information came from

This is an independent, third-party profile of Centers for Medicare and Medicaid Services Enrollments API, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.

The Kin Score and Agent Readiness rating are independently calculated assessments of a company's public API artifacts, scored against a published rubric. They are not certifications, endorsements, security assessments, or audits.

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