IRA Beneficiary Designation: Who to Name and Why It Matters for RMDs

Your IRA passes by beneficiary designation, not your will. Get it wrong and an ex-spouse inherits. Leave it blank and the IRS imposes the harshest distribution rules available. Name the right person in the right way, and you can give heirs decades of tax-deferred growth — or give the full value to charity tax-free. This guide walks the full decision.

Your Beneficiary Designation Overrides Your Will

IRAs and 401(k)s are contractual accounts. When you die, the custodian distributes the account to whoever is named on the beneficiary form — not to whoever your will says should receive it. Courts consistently enforce the beneficiary designation over the will.¹

The practical implications:

• A will saying "leave everything to my children" does not override an IRA form that still names an ex-spouse from a prior marriage.
• A living trust is irrelevant to your IRA unless the trust itself is named as beneficiary on the form.
• If no beneficiary is named, the account typically falls to your estate — triggering the least favorable distribution rules and probate involvement.

Review beneficiary designations after every major life event: marriage, divorce, birth of a child, or death of a named beneficiary. Also review after major tax law changes — the SECURE Act (2019) eliminated the stretch IRA for most non-spouse beneficiaries, making many pre-2020 designation strategies obsolete.

The Three Beneficiary Categories — and the Distribution Rules That Follow

The IRS classifies every IRA beneficiary into one of three categories.² The category determines how long heirs can keep money in the inherited IRA and defer income taxes.

The difference between these categories represents real money. An adult child who inherits a $1.2M traditional IRA under the 10-year rule faces roughly $120,000/year of taxable income for a decade — likely at the 22–24% federal bracket. Under the old stretch-IRA rules (eliminated by SECURE Act), that same beneficiary could have spread distributions over 40+ years, keeping annual income additions modest. That era is gone for most beneficiaries.

Spouse as Primary Beneficiary: Rollover vs. Inherited IRA

The surviving spouse has more flexibility than any other beneficiary. The key choice: roll the inherited IRA into their own, or remain in an inherited IRA.

Option 1: Roll over to own IRA (most common)

The surviving spouse rolls the inherited account into their own IRA (or treats it as their own). This restarts the RMD clock based on the survivor's age — if they're 63, RMDs don't begin until age 73 (or 75 if born 1960+). Roth conversion opportunities continue using the survivor's tax situation. Growth continues under the survivor's own account rules.

Limitation: The survivor's own IRA is subject to the 10% early-withdrawal penalty for distributions before age 59½. If the survivor is 54 and needs income from the account before 59½, rolling over immediately forfeits penalty-free access.

Option 2: Remain in inherited IRA as surviving spouse

A surviving spouse can instead elect to stay in an inherited IRA, where distributions at any age are penalty-free. RMDs from the inherited IRA don't begin until the later of: December 31 of the year after the owner's death, or the year the deceased would have turned 73. After the survivor's financial needs stabilize — or once they reach 59½ — they can still roll the remaining balance into their own IRA and restart the RMD clock at their own age.

Adult Children and Grandchildren: The 10-Year Rule in Practice

For most families, adult children will inherit as non-EDB designated beneficiaries — subject to the 10-year rule. Two critical sub-rules that depend on whether the original owner had started RMDs:

• Owner died before Required Beginning Date (before starting RMDs): No annual distributions are required during the 10 years. The beneficiary can let the full balance compound and take everything in year 10. This creates a potential year-10 tax concentration — distributing $1.5M in one calendar year at ordinary income rates.
• Owner died after Required Beginning Date (had already started RMDs): Annual RMDs are required each year of the 10-year window, based on the beneficiary's life expectancy. The account must still be fully drained by Dec 31 of year 10. T.D. 10001 (July 2024) finalized this rule.³

Minor child of the owner (not grandchild)

A minor child of the account owner qualifies as an EDB — a meaningful exception. The child can take distributions based on their remaining life expectancy until they reach the age of majority (18 in most states, 21 in some). At that point, the 10-year clock starts. A child who inherits at age 12 and reaches majority at 18 has 10 more years: full distribution by age 28. For large accounts, this can still create significant bracket pressure in the beneficiary's 20s.²

Note: This exception applies only to the owner's minor children — not grandchildren, not siblings' children. Grandchildren are designated beneficiaries subject to the standard 10-year rule.

Planning implication for grandchildren

If your estate plan includes leaving your IRA to grandchildren, the 10-year rule applies with no stretch. If you also have charitable intentions, a more efficient structure is often: IRA to charity (no income tax), everything else to grandchildren (who receive stepped-up cost basis on appreciated assets). See the charitable beneficiary section below.

Multiple Beneficiaries: Per Stirpes, Per Capita, and the Separate Accounts Deadline

Per stirpes vs. per capita

When you name multiple beneficiaries, specify how the split works if one predeceases you:

• Per capita (the default at most custodians): if a named beneficiary dies before you, their share passes to the surviving named beneficiaries. A three-way equal split becomes a two-way split if one child dies first.
• Per stirpes: if a named beneficiary predeceases you, their share passes down to their children. The three-way split stays three-way — one share flows to that beneficiary's heirs (your grandchildren through that line).

For most family situations involving children, per stirpes is the better choice. It keeps grandchildren from being inadvertently cut out if their parent predeceases you.

The September 30 beneficiary determination date

The IRS determines who counts as the designated beneficiary as of September 30 of the year following the owner's death.⁴ A named beneficiary who disclaimed their share or fully cashed out their portion before this date is removed from the calculation. This allows a beneficiary with less favorable distribution terms — often an older beneficiary who would pull the group's life expectancy shorter — to step aside if it benefits the remaining heirs.

The December 31 separate accounts deadline

When multiple individuals are named as co-beneficiaries, each can use their own distribution period — but only if they establish separate inherited IRA accounts by December 31 of the year following the owner's death.⁴ Miss that deadline, and all beneficiaries must use the oldest beneficiary's life expectancy divisor, accelerating distributions for everyone and costing younger heirs years of additional tax-deferred compounding.

As a practical matter, beneficiaries often leave the inherited IRA sitting at the original custodian for a year without acting. By the time they realize the deadline passed, they've permanently lost the ability to split accounts on favorable terms. If you're coordinating this for your family in advance, note the December 31 deadline in your estate documents and communicate it to your executor.

Trust as Beneficiary: When It Helps and When It Backfires

Naming a trust as IRA beneficiary serves real purposes in specific situations: a beneficiary with a spending disorder, a special-needs beneficiary who can't receive assets directly without risking government benefits, or minor children who need a trustee to manage distributions. Outside these scenarios, trusts as IRA beneficiaries often produce worse outcomes than naming individuals directly.

See-through trust requirements

For a trust to have its individual beneficiaries "looked through" for RMD purposes — and qualify for anything better than the 5-year rule — it must meet four requirements under IRS regulations:⁵

1. The trust is valid under applicable state law
2. The trust is irrevocable at the owner's death or becomes irrevocable by death
3. All trust beneficiaries are identifiable from the trust document
4. A copy of the trust is furnished to the IRA custodian by October 31 of the year following the owner's death

A trust that fails any of these requirements is treated as a non-designated beneficiary: 5-year rule (before RBD) or ghost life expectancy (after RBD). A $1.2M IRA must be fully distributed within 5 years, with no annual spreading.

Conduit trust vs. accumulation trust

The post-SECURE Act environment makes trusts as IRA beneficiaries significantly more complex than they were under the old stretch rules. Unless you have a specific protective need (special needs trust, creditor protection jurisdiction, spendthrift concern), work with an estate planning attorney who understands the post-SECURE Act 10-year rule implications before naming any trust as your IRA beneficiary.

Charitable Beneficiaries: IRAs Are the Ideal Asset to Leave to Charity

If you plan to make a charitable bequest, your IRA is the most tax-efficient asset to designate for it — by a significant margin.

When a qualified 501(c)(3) charity inherits an IRA, it pays no income tax on the distributions. The full account value reaches the charity's mission. By contrast:

• Heirs who inherit a traditional IRA owe ordinary income tax on every dollar withdrawn — typically 22–24% federal, plus state.
• Heirs who inherit non-IRA assets (brokerage accounts, real estate, closely held stock) receive a stepped-up cost basis at your death — meaning they pay capital gains tax only on appreciation after the date of inheritance, not on decades of prior growth.

Naming a charity directly as IRA beneficiary is simple — just add the organization's EIN to your beneficiary form. Other structures worth discussing with an advisor:

• Donor-advised fund (DAF): your heirs can recommend grants from the inherited DAF over time; the IRA passes tax-free and the family maintains advisory involvement in the charitable giving
• Charitable remainder trust (CRT): provides income to heirs for a term or life, then passes the remainder to charity; can be funded with an inherited IRA though the structure is complex

Common Beneficiary Designation Mistakes

1. Not updating after divorce. A named ex-spouse remains the legal beneficiary unless you change the form. Some states have automatic-revocation laws for divorce, but federal ERISA rules governing 401(k)s frequently preempt state law — the ex-spouse inherits regardless. This is one of the most common and costly inherited IRA disputes in estate litigation.
2. No beneficiary named. The IRA falls to the estate: probate, the 5-year rule (or ghost life expectancy), and no ability to optimize the distribution timing. A five-minute form update at your custodian prevents this entirely.
3. No contingent beneficiary. If the primary predeceases you and no contingent is on file, the account again goes to the estate. Always name both primary and contingent.
4. Naming minor grandchildren directly. A minor can't legally manage an inherited IRA. Without a court-supervised custodianship, assets may be tied up in a restricted account until the grandchild reaches majority — not the inheritance experience you intended.
5. Naming a trust without specialized legal advice. A non-qualifying trust triggers the 5-year rule. An accumulation trust with poor tax planning generates bracket compression of 37% above $16,000. Either outcome is usually worse than naming the individuals directly.
6. Per capita when per stirpes was intended. "My children equally" without specifying per stirpes means a predeceased child's share passes to their surviving siblings, not to their children. Your grandchildren through that line receive nothing.
7. Never reviewing after the SECURE Act (2019). Any beneficiary plan designed before 2020 was built around the stretch IRA — which no longer exists for most non-spouse beneficiaries. The 10-year rule changes the calculus on trust structures, large traditional IRA balances, and tax bracket management for heirs. If you haven't revisited this since 2019, revisit it now.

Coordinating Beneficiary Designation with Your Active RMD Strategy

Beneficiary choices don't sit in isolation — they interact with what you do during your lifetime:

• Roth conversions before 73 reduce the taxable balance your heirs inherit. Every dollar converted pre-RMD is a dollar your heirs inherit as tax-free Roth (still subject to the inherited Roth 10-year rule, but with no annual RMD requirement and no income tax on distributions). If your plan includes substantial Roth conversion, the tax efficiency of your beneficiary designation improves significantly on the converted portion.
• QCDs reduce the traditional IRA balance over time. Giving up to $111,000/year directly from your IRA to charity post-70½ both satisfies RMDs and shrinks the taxable inheritance. If you have both charitable and non-charitable heirs, lifetime QCDs to charity combined with naming specific individuals as IRA beneficiaries can be more efficient than a charitable trust structure.
• Spousal rollover interacts with future IRMAA planning. If your spouse rolls over your IRA into their own, the combined balance drives their future RMDs — potentially pushing them into higher IRMAA Medicare surcharge tiers for years. A Roth conversion strategy that reduces your IRA balance before your death benefits your spouse's Medicare costs for decades, not just your own.