Coordination of benefits (COB) are the rules for how insurance pays when a patient has coverage under more than one plan. You can set up defaults in Family Module 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.

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

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).

• If the secondary allowed amount was $110, secondary would pay the lesser of $88 or ($110 - $80), so $30.
• If the secondary allowed amount was $90, secondary would pay the lesser of $72 or ($90 - $80), so $10.
• As a second example, on a $100 procedure, primary might pay $50 (50% of its allowed fee).
• If the secondary allowed amount was $110, secondary would pay the lesser of $55 or ($110 - $50), so $55.
• If the secondary allowed amount was $90, secondary would pay the lesser of $45 or ($90 - $50), so $40.

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).

• If the secondary allowed amount was $110, secondary would pay the lesser of $88 or $20, so $20.
• If the secondary allowed amount was $90, secondary would pay the lesser of $72 or $20, so $20.
• As a second example, on a $100 procedure, primary might pay $50 (50% of its allowed fee).
• If the secondary allowed amount was $110, secondary would pay the lesser of $55 or $50, so $50.
• If the secondary allowed amount was $90, secondary would pay the lesser of $45 or $50, so $45.

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).

• If secondary allowed amount was $1200, secondary deductible was $50 and secondary percentage was 80%, then secondary would pay: $170
• 170 = (1200 - 50) * .8 - 750

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

• If secondary allowed amount was $110, secondary would pay $88 - $80 = $8.
• If secondary allowed amount was $90, secondary would pay $72 - $80 = $0.
• As a second example, on a $100 procedure, primary might pay $50 (50% of its allowed fee).
• If secondary allowed amount was $110, secondary would pay $55 - $50 = $5.
• If secondary allowed amount was $90, secondary would pay $45 - $50 = $0.

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 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.