Ambetter Health is the ACA Marketplace brand of Centene Corporation, the largest Marketplace insurer and the largest Medicaid insurer in the country. Centene had 25.7 million members at the end of September 2026, including 3.4 million Ambetter Marketplace members and 11.9 million Medicaid members company results.
Centene also sells Medicare Advantage and Part D plans under the Wellcare brand and runs state Medicaid plans under local names such as Superior HealthPlan in Texas, Sunshine Health in Florida and Peach State Health Plan in Georgia.
Updated November 2026. This profile draws on company filings, federal data and Health Plan News analysis. It is independent of Ambetter; for questions about your coverage, call the number on your member ID card.
Ambetter at a Glance
| Item | Details |
|---|---|
| Parent company | Centene Corporation (NYSE: CNC) |
| Headquarters | St. Louis, Missouri |
| CEO | Sarah M. London |
| Insurance brands | Ambetter Health, Wellcare, state Medicaid plans |
| 2025 revenue | $194.8 billion |
| Members | 25.7 million (September 30, 2026) |
| ACA Marketplace | 3.4 million members in 27 states |
| Medicaid | 11.9 million members in 30 states |
| Medicare | 954,000 Medicare Advantage; 8.9 million Part D |
The Largest ACA Marketplace Insurer
Ambetter led the ACA exchange in 12 states in mid-2024, including Georgia, Indiana, Missouri, Ohio and Tennessee, and was second in nine more, according to the AMA. Its Marketplace membership fell from 5.5 million at the end of 2025 to 3.4 million by September 2026 after the expanded premium tax credits expired.
For 2027, Ambetter is adding 55 counties in seven states, including Illinois, Michigan, New Jersey and Texas, and leaving Delaware and New Hampshire (source). It is also adding condition-specific plans for diabetes, asthma and heart failure.
Medicaid
Medicaid is 57% of Centene’s revenue. It holds contracts in 30 states, with Florida and New York its largest. For 2027 it is leaving Arkansas’s ARHOME Medicaid expansion program, affecting about 77,000 members (source). See our Medicaid managed care by state data.
Wellcare Medicare
Centene is cutting Medicare Advantage the hardest of any public insurer for 2027, leaving 344 counties, about 20% of its footprint (source). Its average star rating fell to 3.14, and seven Wellcare contracts were rated 2.5 stars.
Ambetter by the Numbers: Health Plan News Data
- Commercial (employer and individual) market: largest insurer in 0 states and second-largest in 2, based on 2024 AMA data.
- Aca exchange market: largest insurer in 12 states (Arkansas, Georgia, Indiana, Kansas, Louisiana, Mississippi, Missouri, Nebraska and others) and second-largest in 9, based on 2024 AMA data.
- Claim denials: its HealthCare.gov plans denied 18.5% of in-network claims in 2024 across 17 states, compared with 18.7% for all HealthCare.gov insurers (federal Transparency in Coverage data compiled by KFF).
Compare insurers in every state on our health insurance market share by state page and our claim denial rates by insurer report.
Recent Ambetter News
- 2025 guidance withdrawal: Centene withdrew its 2025 earnings guidance in July 2025 after data showed sicker-than-expected Marketplace enrollees, and later recorded a $6.7 billion goodwill write-down; it posted a $6.7 billion net loss for 2025. (source)
- Recovery in 2026: Third-quarter 2026 revenue was $50.6 billion, and Centene raised its 2026 adjusted earnings guidance to more than $5.20 a share. (source)
- Shareholder lawsuit: A securities class action alleges the company inflated guidance between December 2024 and June 2025. (source)
How To Contact Ambetter
| Purpose | Contact |
|---|---|
| Ambetter members | Number on your member ID card or your state Ambetter page |
| Ambetter website | ambetterhealth.com |
| Corporate website | centene.com |
For profiles of other carriers, see our List of Health Insurance Companies and follow our Health Insurance Companies hub.
Sources
Ambetter Health FAQ; Ambetter Health FAQ footer; Becker’s / healthcaredive.com (CMS 2027 landscape data); Becker’s Payer Issues – 8 things to know about 2027 MA star ratings; Becker’s Payer Issues – MA plans with 2.5 stars or lower in 2027; Centene; Centene – Our History; Centene 10-K FY2025; Centene 2025 guidance withdrawal release; Centene Q3 2026 earnings release; American Medical Association, Competition in Health Insurance (2025 update); KFF, Medicare Advantage in 2026; CMS Transparency in Coverage public use file (2024, via KFF).