MMC Benefits Handbook
Impact on Benefits
Your contribution to cover a domestic partner and the dependent child(ren) of a domestic partner is the same as the cost to cover other eligible family members. The contributions are made on a before-tax basis. However, because of IRS requirements, the total cost (Company's cost plus your contributions) for providing healthcare will be imputed as taxable income to you unless your domestic partner (or his or her child(ren)) qualifies as your tax dependent.
If your domestic partner (or his or her child(ren)) qualifies as a dependent under Internal Revenue Code Section 152 and IRS Publication 501 (that is, are your tax dependents), the cost of their coverage would not be imputed as taxable income to you.
You should review your beneficiary designations for all your benefit plans.
Note: Domestic partners are not treated as spouses under the tax law or for purposes of the 401(k) Savings & Investment Plan or the US Retirement Program. However, the US Retirement Program does provide survivor benefits to qualified domestic partners. See "Eligible Survivor" in the Marsh & McLennan Companies Retirement Plan, Benefit Equalization Plan and Supplemental Retirement Plan sections of the Benefits Handbook for specific domestic partner plan details.