What this page covers

  1. What COB is and why claims deny on it
  2. Updating COB with payers and Medicare
  3. How Flexbone runs coordination of benefits
CARC 22the denial code for care that may be covered by another payer per COB
Primary vs secondaryclaims must go to the correct payer first or they reject
MSP rulesMedicare Secondary Payer rules decide order when Medicare is involved

Coordination of benefits decides which plan pays first when a patient has more than one, and getting it wrong is a common, avoidable denial. When a payer believes another plan is primary, it rejects the claim, often with CARC 22. The fix is determining the correct order of liability and getting the COB record updated. Flexbone does both.

What COB is and why claims deny on it

Coordination of benefits is the set of rules that determines the order in which multiple plans pay: which is primary, which is secondary. Patients with a spouse's plan, with both commercial and Medicare or Medicaid, or with retained coverage after a job change commonly have more than one plan. When a claim goes to a payer that believes it is not primary, it denies, frequently with CARC 22, care may be covered by another payer per coordination of benefits, or a related COB code. These denials are avoidable when the order is known and the COB record is current.

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Updating COB with payers and Medicare

The resolution is usually a phone call. The patient's COB record at the payer is stale or missing, and someone has to call to confirm the other coverage, establish the correct primary, and update the record. When Medicare is involved, Medicare Secondary Payer rules govern the order, and the COB update may run through the Benefits Coordination and Recovery Center. Flexbone places these calls, confirms the order of liability, gets the COB record updated, and captures the reference number so the corrected claim pays.

How Flexbone runs coordination of benefits

Flexbone works COB on the front end and the back end. During eligibility, it detects multiple coverages and establishes the likely order so the claim goes to the right payer first. On denials, it works the CARC 22 and related COB rejections: calling the payer, correcting the record, and resubmitting. Results write back to the practice management system, and cases needing patient input, such as confirming other coverage, are routed to staff. The work is scoped to your payers and patient mix.