This page, Important One Care Contacts, is offered by

Important One Care Contacts

If you have questions, see below for ways you can contact us.

If you have questions about:

  • How to choose a One Care plan
  • Other health care options through Medicare and/or MassHealth

Contact SHINE (Serving the Health Insurance Needs of Everyone)

SHINE counselors can work with you and your caregivers to help you understand your options. They are trained to assist people who have Medicare and MassHealth and will provide impartial information about your health insurance options. A counselor can work with you in person, by phone, or through email.

Hours: Monday – Friday, 9:00 a.m. - 5:00 p.m.

Phone: (800) 243-4636

TTY: (800) 439-2370

If you have questions about MassHealth or One Care:

  • Eligibility
  • Enrollment or disenrollment, including changing One Care plans
  • Opting out of passive enrollment

Contact the MassHealth Customer Service Center:

Hours: Monday – Friday, 8:00 a.m. - 5:00 p.m.

Phone: (800) 841-2900

TTY: (800) 497-4648

If you have questions about Medicare, including Medicare Part D

  • Eligibility
  • Enrollment

Contact 1-800 Medicare:

Hours: 24 hours a day, 7 days a week

Phone: (800) 633-4227

TTY: (877) 486-2048

If you are enrolled in One Care and have questions about:

  • Contacting your care manager
  • Contacting your Long-Term Supports Coordinator
  • Making appointments
  • Transportation
  • Your One Care plan coverage
  • Other questions about your health care

Contact your One Care plan directly. Visit the Learn about One Care plans page for more information.

If you are enrolled in One Care and have questions about:

  • Addressing a problem or concern with your One Care plan
  • One Care benefits or rights
  • Information about how grievances or appeals work
  • Other One Care information

Contact the One Care Ombudsman (OCO)

The One Care Ombudsman (OCO) is an independent program that helps individuals address concerns or conflicts that may interfere with their enrollment in One Care or their access to One Care benefits and services. The OCO works with MassHealth and each of the One Care plans to help resolve concerns so that persons with disabilities can receive their health care benefits and exercise the rights to which they are entitled in One Care. OCO staff can work with you in person or over the phone.

Hours: Monday – Friday, 9:00 a.m. - 4:00 p.m.

Phone: (855) 781-9898

TTY: call 711



Visit the OCO in person at:

11 Dartmouth St., Suite 301

Malden, MA  02148

Walk-in Hours:

Mondays 1:00 p.m. - 4:00 p.m. and Thursdays 9:00 a.m. - 12:00 p.m.

The OCO offices are wheelchair accessible. You can also set up an in-person appointment outside of walk-in hours by calling or emailing the OCO.