Coordination of Benefits ( COB )

Coordination of benefits (COB) are the rules for how insurance pays when a patient has coverage under more than one plan.

On the Secondary Insurance plan, in the Edit Insurance Plan window, Other Ins tab, select a Coordination of Benefits rule.

Set the default Coordination of Benefits rule in Preferences. There are many different ways to calculate COB, made even more complicated by various State laws. Non-duplication rules can vary, depending on the carrier.

Open Dental has the following different COB Rule options.

Basic: Secondary pays the lesser of:

  1. The amount that it would have paid in the absence of any other coverage.
  2. The secondary allowed amount minus what primary paid.

For example, on a $100 procedure, primary might pay $80 (80% of its allowed fee).

Standard: Secondary pays the lesser of:

  1. The amount that it would have paid in the absence of any other coverage.
  2. The patient's portion under the primary plan.

For example, on a $100 procedure, primary might pay $80 (80% of its allowed fee).

Carve Out: (Non-Duplication) Secondary reduces what they will pay by what primary paid.

Calculation used: Secondary InsEst = (Secondary Allowed - Secondary Deductible) * Secondary Percentage - PaidOther

Example with deductible: On a $1500 procedure, primary might pay $750 (50% of its allowed fee).

Example without deductible (Non-Duplication: On a $100 procedure, primary might pay $80 (80% of its allowed fee).

Secondary Medicaid: Secondary reduces what they pay by what primary pays. The estimated patient portion becomes a write-off for the secondary insurance. Only use this rule if when allowed to bill Medicaid as secondary.

Calculation used: ProcFee - Pri Ins Pay Est (or Ins Pay) - Pri WO - Sec Ins Est

Examples: On a $100 procedure, primary insurance might allow $70, pay $35, and write off $30. Secondary insurance might allow $20, pay $0, and write off $35. The patient will pay $0.

On a $100 procedure, primary insurance might allow $40, pay $20 and write off $60. Secondary insurance might allow $30, pay $10 and write off $10. The patient will pay $0.