If your ex-wife is still listed as the beneficiary on your 401(k), she will almost certainly receive the account if you die before changing the form. Federal law requires the plan administrator to pay whoever is named on the beneficiary designation, and a divorce decree, a will, or your family’s understanding of your wishes will not override it.
Why the Form on File Controls
Private 401(k) plans are governed by the Employee Retirement Income Security Act of 1974. ERISA requires plan fiduciaries to administer the plan “in accordance with the documents and instruments governing the plan.”1Office of the Law Revision Counsel. 29 U.S. Code 1104 – Fiduciary Duties The plan administrator looks at the beneficiary form and pays the person listed. They do not investigate whether you divorced, remarried, had children, or meant to update your paperwork.
ERISA also preempts state law. The statute “shall supersede any and all State laws insofar as they may now or hereafter relate to any employee benefit plan” it covers.2Office of the Law Revision Counsel. 29 USC 1144 – Other Laws Roughly half the states have “revocation-on-divorce” statutes that automatically remove an ex-spouse as a beneficiary when a marriage ends. Those laws do not reach ERISA-governed 401(k)s. The Supreme Court struck down a Washington statute that tried to do exactly that in Egelhoff v. Egelhoff (2001), holding that forcing administrators to apply 50 different state rules would defeat Congress’s goal of uniform plan administration.3Legal Information Institute. Egelhoff v. Egelhoff, 532 U.S. 141 (2001)
So your ex-wife stays on the form until you take her off. It does not matter what state you live in.
Your Divorce Decree Does Not Change the Beneficiary
This is the trap that catches families. Divorce decrees routinely include language saying each spouse waives any interest in the other’s retirement accounts. That language does not update your 401(k). The plan administrator is not required to read your divorce decree, interpret its waiver, or treat it as a beneficiary change.
In Kennedy v. Plan Administrator for DuPont Savings & Investment Plan (2009), a man’s divorce decree contained his ex-wife’s signed waiver of any interest in his retirement benefits. He never updated the plan’s beneficiary form. When he died, the plan paid the ex-wife. His estate sued, and the Supreme Court unanimously sided with the plan, holding that the estate’s claim “stands or falls by the terms of the plan.”4Justia. Kennedy v. Plan Administrator for DuPont Savings and Investment Plan, 555 U.S. 285 (2009) The plan had its own procedure for changing a beneficiary. The ex-wife had not used it, and the decree was no substitute.
The rule is simple. For a 401(k), the only document that matters is the beneficiary form filed with the plan.
How to Take Your Ex-Wife Off the Form
Updating the beneficiary is the fix, and it is straightforward, but you have to actually do it. Contact your employer’s HR department or the plan administrator directly and ask for the official beneficiary designation form. Many plans now handle this through an online portal; some still require a signed paper form returned by mail. A verbal instruction, an email to a coworker, or a note in your divorce file will not count.
When you fill it out:
- Use the new beneficiary’s full legal name, date of birth, and Social Security number. Vague labels like “my children” invite disputes.
- If you name more than one person, specify the percentage each receives.
- Name at least one contingent beneficiary in case the primary dies before you.
- Keep a copy of the submitted form and any confirmation from the plan.
Do this the week your divorce is finalized. The gap between the decree and the updated form is exactly where families lose money.
If You’ve Remarried, Your New Spouse Has Rights
ERISA protects current spouses. If you have remarried and want to name anyone other than your new spouse as primary beneficiary, your spouse must consent in writing. The consent must specifically acknowledge the effect of the election and be witnessed by a plan representative or a notary public.5Office of the Law Revision Counsel. 29 U.S. Code 1055 – Requirement of Joint and Survivor Annuity and Preretirement Survivor Annuity
Even for 401(k) plans not required to provide joint and survivor annuities, any remaining balance generally must be paid to the surviving spouse at the participant’s death unless that spouse has consented to a different beneficiary.6Internal Revenue Service. Fixing Common Plan Mistakes – Failure to Obtain Spousal Consent The practical effect is that a new spouse may have a stronger claim than the ex-wife still listed on the form, depending on the plan’s terms and whether spousal consent was ever obtained. Do not rely on this to bail you out. Update the form.
What If You Remove Her but Name No One Else
If you take your ex-wife off and die before naming a replacement, the plan’s default rules take over. Most plans follow a hierarchy that pays the surviving spouse first, then the participant’s children, then the estate. The order varies by plan, so read the summary plan description.
Passing through the estate is not a catastrophe, but it is slower. The money becomes subject to probate, court oversight, potential creditor claims, and delays. Naming a beneficiary keeps the funds out of probate.
One Boundary: IRAs Work Differently
IRAs are not governed by ERISA. In states with revocation-on-divorce laws, those statutes generally do apply to IRAs and can automatically remove an ex-spouse as beneficiary. That does not help you with a 401(k). If you have both, don’t assume the same rules cover them. Update both forms.
If Your Ex-Wife Has Already Been Paid
Once the plan distributes the money, challenging the payment itself is essentially impossible. The administrator did what ERISA required. Any recovery has to come from the ex-wife directly, not the plan.
The typical route is a lawsuit by the estate or the intended heirs against the ex-wife, arguing that the waiver in the divorce decree obligates her to hand the money over. Courts asked to enforce that obligation use a tool called a “constructive trust,” which treats the recipient as holding money that rightfully belongs to someone else.
Whether this works depends on where the case is filed. The Supreme Court in Kennedy deliberately left the question open, noting in a footnote that it expressed no view on “whether the Estate could have brought an action in state or federal court against Liv to obtain the benefits after they were distributed.”4Justia. Kennedy v. Plan Administrator for DuPont Savings and Investment Plan, 555 U.S. 285 (2009) Federal appeals courts have split. The Third Circuit, in Estate of Kensinger v. URL Pharma (2012), allowed an estate to recover from an ex-spouse, reasoning that ERISA’s concern with plan administration ends once distribution is complete. The Ninth Circuit, in Carmona v. Carmona (2008), rejected the same approach, calling a constructive trust an impermissible “end-run around ERISA’s rules.” The Seventh Circuit has also rejected these claims.
The strength of the waiver language matters as much as the circuit. A generic clause saying “each party waives all claims to the other’s assets” is far weaker than a waiver that names the specific 401(k) plan and expressly relinquishes any beneficiary interest. If you are the intended heir trying to recover, expect a real fight and consult a lawyer in your jurisdiction.
Taxes on Whoever Receives the Money
Whoever ends up with the 401(k) owes income tax on the distributions. Beneficiaries include the taxable amount in gross income and report it the way the original account holder would have.7Internal Revenue Service. Retirement Topics – Beneficiary For a traditional 401(k) funded with pre-tax dollars, the full distribution is ordinary income.
An ex-wife who inherits as a named beneficiary after your death is not treated as a spouse for distribution purposes. Spouses can roll an inherited 401(k) into their own IRA and stretch out distributions. An ex-wife is a non-spouse designated beneficiary, generally subject to the 10-year rule: the account must be emptied by the end of the tenth year after your death.7Internal Revenue Service. Retirement Topics – Beneficiary A large balance compressed into 10 years of distributions can push her into a higher bracket each year.
For intended heirs who lose the account, there is no tax deduction for the lost inheritance. Even a successful constructive trust recovery does not change the tax treatment for the ex-wife on amounts she has already received. The cleanest, cheapest fix is still the one that takes 15 minutes: request the form from your plan and change the name.