The short answer: the form wins
A beneficiary designation is a direct contractual instruction to a financial institution: it transfers the named account to the named person immediately upon your death, completely outside of probate, regardless of anything your will says. Your will only governs assets that have no surviving joint owner and no named beneficiary. For most families, retirement accounts and life insurance — often their two largest assets — never touch the will at all.
The institution is legally obliged to pay whoever the form names, and courts consistently uphold that result. If your will says your sister should receive your 401(k) but the plan's beneficiary form still names your college roommate, your college roommate gets the money. The will cannot override the contract.
Which accounts use a beneficiary designation
Life insurance policies and annuities pass by beneficiary designation, as do retirement accounts — 401(k)s, 403(b)s and IRAs. Bank accounts use a payable-on-death (POD) designation; brokerage and investment accounts use a transfer-on-death (TOD) designation. All of them pass directly to the named person, with no court supervision, no public record and no delay while an estate is settled.
The designation only works if it is filled in. If you name your estate as the beneficiary, or leave the form blank, the proceeds are pulled into the probate process — and the plan's default rules take over, which may not match what you wanted at all.
POD and TOD, in plain terms
A payable-on-death designation is a contract between you and your bank. You can add one to a checking account, a savings account, a money market account or a certificate of deposit. During your lifetime the POD designation gives the named person no rights to the money at all; at your death the bank transfers the full balance directly to them, bypassing probate entirely.
A transfer-on-death designation is the equivalent for brokerage and investment accounts holding stocks, bonds or mutual funds: the securities pass directly to the named beneficiary without probate. TOD registrations follow the Uniform Transfer-on-Death Securities Registration Act, adopted in most states. The practical difference is mainly the asset type: POD covers bank deposits, TOD covers securities — and in some states, real estate.
Where the rule bends
Divorce is the case that catches people out. Many states have laws that automatically revoke a non-probate transfer to a former spouse when the marriage ends, covering POD accounts, TOD designations and similar instruments — but the rules vary by state and by asset, and life insurance provisions are sometimes expressly excluded from them.
The big exception is employer retirement plans. Federal law — ERISA, 29 U.S.C. § 1144 — makes federal law supreme over state law for employer-sponsored plans, and the plan administrator must follow the plan documents. Divorce does not automatically remove an ex-spouse from a 401(k): unless you file a new beneficiary form with the plan, the ex-spouse can still receive it. That is the single most expensive forgotten form in estate planning.
One more failure mode: if every named beneficiary dies before the account owner, the designation effectively fails, and the account balance reverts to the owner's estate and goes through probate. Naming a contingent — backup — beneficiary on each form closes that gap.
Why this matters for life insurance
Life insurance proceeds pass directly to the named beneficiary, outside probate — which is one reason life insurance is such a useful estate planning tool. The death benefit is excluded from the beneficiary's gross income, and proceeds paid to a named individual are generally beyond the reach of the insured's creditors. Name the estate instead, and the proceeds can be subject to estate creditors and probate delay.
The amount and the kind of policy are separate questions from who receives it: the term vs whole life guide explains the choice of policy, and the life insurance claims guide walks through what happens at claim time — including what a beneficiary needs to have in hand.
The review habit
Every major life event — marriage, divorce, a birth, a death in the family — should trigger a review of every beneficiary form you have signed, not just your will. A form signed decades ago for a person who is no longer in your life is still the form the institution will follow.
The stakes have risen since the SECURE Act of 2019: most non-spouse beneficiaries of an inherited IRA must now empty the account within 10 years, with IRS final regulations taking full effect in January 2025 — which makes a misnamed IRA beneficiary significantly more costly than it was before. Review the forms the way you would review the will: together, and after every change in the family.
Worked example
Consider two ILLUSTRATIVE cases. In the first, a will leaves a 401(k) to a sister, but the plan's beneficiary form — signed years earlier — still names a college roommate. The roommate receives the 401(k); the will's instruction has no effect on it. In the second, a will leaves a savings account to a son, but the account carries a POD designation naming a daughter. The daughter receives the balance directly from the bank, outside probate, and the will does not change that. These are ILLUSTRATIVE contrasts to explain how designations work; they describe no real person or account, and state rules vary.
Illustrative example only — not a fact about any real policy.