U S Department of Health and Human Services www.hhs.gov
  CMS Home > Medicare > COB - General Information > Overview
COB - General Information


The Coordination of Benefits (COB) Contractor consolidates the activities that support the collection, management, and reporting of other insurance coverage for Medicare beneficiaries. The purposes of the COB program are to identify the health benefits available to a Medicare beneficiary and to coordinate the payment process to prevent mistaken payment of Medicare benefits. The COB Contractor does not process claims, nor does it handle any mistaken payment recoveries or claims specific inquiries. The Medicare intermediaries and carriers are responsible for processing claims submitted for primary or secondary payment. To resolve your questions regarding whom to contact, see below:

 Contact the COB Contractor to:

  • Report employment changes, or any other insurance coverage information.
  • Report a liability, auto/no-fault, or workers compensation case.
  • Ask general Medicare Secondary Payer (MSP) questions/ concerns.
  • Ask questions regarding Medicare Secondary Development (MSP) letters and questionnaires.

 Contact your local Medicare intermediary or carrier to:

  • Answer your questions regarding Medicare claim or service denials and adjustments.
  • Answer your questions concerning how to bill for payment.
  • Process claims for primary or secondary payment.
  • Accept the return of inappropriate Medicare payment.

 Contact 1-800-MEDICARE (1-800-633-4227) to:

  • Obtain general Medicare information.
  • Obtain information about Medicare Health Plan choices.
  • Order Medicare publications.

 Contact SSA to:

  • Enroll in the Medicare program.
  • Replace your Medicare card.
  • Change your address.
  • Verify Medicare coverage.

There are no Downloads
Related Links Inside CMS

Beneficiary & Advocate Services

Coordination of Benefits Agreement

Coordination of Benefits Prescription Drugs

Employer Services

Insurer Services

IRS-SSA-CMS Data Match

Medicare Initial Enrollment Questionnaire

Medicare Secondary Payer & You

Provider Services

Workers Compensation Agency Services

Related Links Outside CMSExternal Linking Policy


Page Last Modified: 02/14/2005 3:39:00 PM
Help with File Formats and Plug-Ins

Submit Feedback