It sounds like the setup for a law-school exam:

A husband and wife are involved in the same automobile accident. One is pronounced dead at the scene. The other is transported to the hospital but dies several hours later.

Who inherited from whom?

Or consider an even harder case: both spouses die at the scene, and no one can determine which died first.

The answer can matter enormously.

If Husband legally survived Wife, even for a short period, property might first pass from Wife to Husband and then from Husband to his beneficiaries. If Wife survived Husband, the same assets might ultimately end up with an entirely different family.

Fortunately, modern estate law generally does not require families to litigate whether one spouse survived another by seconds.

That is the purpose of simultaneous-death and survivorship statutes.

Although the details vary from state to state, the dominant modern approach is remarkably simple:

Five days matter.

The Uniform Simultaneous Death Act uses a 120-hour—or five-day—survival period as its default rule. The Uniform Law Commission describes the rule as requiring one person to survive another by 120 hours to avoid disputes resulting from simultaneous or quickly successive deaths.

But that does not mean every estate plan should simply rely on state law.

In fact, simultaneous-death provisions are one of those obscure estate-planning clauses that may look like boilerplate until the day they determine where hundreds of thousands—or millions—of dollars ultimately go.

What Is a Simultaneous Death Law?

Simultaneous-death statutes address a deceptively simple question:

What happens when the right to inherit depends upon Person A surviving Person B, but they die at approximately the same time?

Historically, this could produce bizarre disputes.

Imagine spouses David and Maria die in an airplane crash. David’s will leaves everything to Maria, then to his children. Maria’s will leaves everything to David, then to her siblings.

If David survived Maria by two minutes, Maria’s property potentially moves through David’s estate.

If Maria survived David by two minutes, David’s property potentially moves through Maria’s estate.

Two minutes could therefore determine which side of the family ultimately receives the couple’s wealth.

Modern simultaneous-death statutes attempt to prevent precisely this kind of result.

Enter the Uniform Simultaneous Death Act

Versions of the Uniform Simultaneous Death Act have existed for decades. The modern uniform approach establishes a default 120-hour survival requirement.

In other words:

A beneficiary generally must survive the decedent by five days before being treated as having survived the decedent for purposes covered by the statute.

The precise reach of the rule depends upon the applicable state’s law and the governing document.

For example, Virginia provides that an individual who cannot be established by clear and convincing evidence to have survived another individual by 120 hours is generally deemed to have predeceased that individual.

New York similarly applies a 120-hour rule to covered property interests and governing instruments.

Texas provides, among other things, that a devisee who fails to survive the testator by 120 hours is generally treated as having predeceased the testator, subject to statutory exceptions and contrary provisions in the will.

The Uniform Simultaneous Death Act is therefore best understood as a default rule of construction rather than an assumption that doctors somehow consider two people medically to have died at the same moment.

The Five-Day Rule Can Produce a Strange Legal Fiction

Suppose Robert dies Monday at 8:00 a.m.

His wife, Susan, survives the accident but dies Thursday at 3:00 p.m.

Susan unquestionably survived Robert in the ordinary sense.

But she did not survive him by 120 hours.

Under a statute applying the 120-hour rule, Susan may therefore be treated for inheritance purposes as though she died before Robert.

That sounds impossible because it is.

It is a legal fiction created to produce a cleaner property-distribution result.

And it can be extremely useful.

Instead of Robert’s property passing to Susan, becoming part of Susan’s estate, and then passing again upon Susan’s death, Robert’s property may proceed directly to Robert’s alternate beneficiaries.

Why Does the Law Do This?

There are several reasons.

1. It can prevent unnecessary double administration.

Without a survivorship rule, property could theoretically pass from Estate A into Estate B within hours or days, requiring additional administration merely to send the property somewhere else.

2. It reduces fights about microscopic differences in death times.

Modern medicine makes this especially important.

One person might technically retain cardiac activity longer. Another might be resuscitated temporarily. Life support can further complicate the timeline.

Estate distribution should not necessarily turn on whether one spouse’s heart stopped at 10:42 p.m. and the other’s at 10:47 p.m.

3. It can better approximate what people actually intended.

Most married couples leaving property to each other are contemplating a surviving spouse who will actually use and enjoy the inheritance.

They probably are not thinking:

“I want everything to go to my spouse even if my spouse survives me unconscious for eleven hours and then dies from injuries suffered in the same accident.”

A survivorship requirement can prevent that unintended result.

What Happens to Joint Property?

Simultaneous death becomes especially interesting with jointly owned property.

Suppose spouses own a $700,000 home jointly with a right of survivorship.

Ordinarily, when one spouse dies, the survivor becomes owner of the property.

But what if neither spouse satisfies the applicable survivorship requirement?

Modern simultaneous-death statutes can effectively divide the interests rather than arbitrarily selecting one person as the survivor.

For example, the modern uniform approach to co-owned survivorship property generally treats portions of the property as though each co-owner survived the other when the required survivorship cannot be established.

That can cause each spouse’s share to move through that spouse’s respective estate plan rather than the entire property becoming part of one spouse’s estate.

This distinction can completely change the ultimate beneficiaries.

What About Life Insurance?

Consider this scenario:

Dad owns a $1 million life-insurance policy.

Mom is the primary beneficiary.

Their children are contingent beneficiaries.

Dad and Mom are involved in the same accident. Dad dies immediately. Mom dies three hours later.

Who gets the $1 million?

Do not automatically assume Mom’s estate.

The answer can depend upon the policy language, beneficiary designation, applicable state statute, and any contractual survivorship provision.

Simultaneous-death statutes may encompass insurance policies and other beneficiary-designated assets. New York, for example, expressly defines covered “governing instruments” broadly enough to include insurance and annuity policies, retirement plans, TOD registrations and various other dispositive instruments.

This is one reason beneficiary-designation reviews are an important part of estate planning.

Your will is not necessarily controlling your life insurance, retirement account or TOD account.

The Rule Isn’t Always 120 Hours

The 120-hour rule has become extremely influential, but estate planners should not describe American law as though every state has enacted precisely the same statute in precisely the same form.

States have adopted the Uniform Simultaneous Death Act, Uniform Probate Code survivorship concepts, older versions of simultaneous-death legislation, or state-specific rules.

Even where two states both use 120 hours, there can be meaningful differences concerning:

intestacy;
wills;
trusts;
jointly owned property;
life insurance;
retirement accounts;
TOD/POD accounts;
marital rights;
evidentiary standards;
escheat;
tax-sensitive dispositions; and
exceptions when the governing instrument says something different.

That distinction becomes particularly important for people who own property in multiple states.

A 50-State Estate-Planning Overview

The following is a planning overview rather than a substitute for checking the current statute applicable to a particular estate, trust, beneficiary designation or asset. Simultaneous-death statutes have been revised over time, and the governing instrument can override many statutory defaults.

State	General Planning Approach
Alabama	Simultaneous-death/survivorship rules apply; review Alabama probate law and the governing instrument.
Alaska	Uses modern UPC-style survivorship principles, generally including a 120-hour rule.
Arizona	Uses UPC-style survivorship rules, generally requiring 120 hours.
Arkansas	Has adopted modern simultaneous-death legislation incorporating the 120-hour concept.
California	California probate law contains survivorship rules, including a 120-hour requirement in important succession contexts, subject to statutory and document-specific exceptions.
Colorado	UPC jurisdiction; generally applies the 120-hour survivorship concept.
Connecticut	Has simultaneous-death rules, but practitioners should check the particular statutory provisions and governing instrument rather than assume the complete UPC formulation applies.
Delaware	Has statutory simultaneous-death rules; Delaware-specific provisions and governing documents should be reviewed.
Florida	Florida probate law addresses survivorship and simultaneous death; the particular will, trust, beneficiary designation and statutory provision must be examined rather than assuming one universal rule governs every asset.
Georgia	Has statutory survivorship/simultaneous-death rules; Georgia-specific treatment should be checked for the asset involved.
Hawaii	UPC-style jurisdiction generally employing the 120-hour concept.
Idaho	UPC-based probate system generally using a 120-hour survivorship rule.
Illinois	Has statutory simultaneous-death/survivorship provisions; the governing instrument and Illinois statute should be checked.
Indiana	Has statutory survivorship rules; application varies with the type of transfer and governing instrument.
Iowa	Uses statutory survivorship/simultaneous-death rules; check the current probate provisions for the particular transfer.
Kansas	Has adopted modern Uniform Simultaneous Death Act concepts, including the 120-hour approach.
Kentucky	Uses statutory simultaneous-death provisions and modern uniform-law concepts; review Kentucky-specific exceptions.
Louisiana	Louisiana is different because of its civil-law succession system. Its survivorship and commorientes rules should be analyzed under Louisiana succession law rather than simply importing the Uniform Probate Code.
Maine	UPC jurisdiction generally applying a 120-hour survival requirement.
Maryland	Important 2026 development: Maryland enacted legislation in 2026 conforming its Uniform Simultaneous Death Act to the modern uniform approach, including a 120-hour survival requirement.
Massachusetts	Massachusetts probate law follows modern UPC-style survivorship concepts, generally including 120 hours.
Michigan	UPC jurisdiction generally applying the 120-hour rule.
Minnesota	UPC-style probate law generally incorporates the 120-hour survivorship concept.
Mississippi	Has simultaneous-death legislation; Mississippi’s particular statutory rules should be checked for the asset involved.
Missouri	Has statutory simultaneous-death/survivorship provisions; governing documents can be critical.
Montana	UPC jurisdiction generally applying 120-hour survivorship principles.
Nebraska	UPC jurisdiction generally using the 120-hour rule.
Nevada	Has statutory simultaneous-death/survivorship provisions; review Nevada’s specific rules and the governing instrument.
New Hampshire	Has adopted modern Uniform Simultaneous Death Act concepts, generally including the 120-hour rule.
New Jersey	New Jersey probate law uses a 120-hour survivorship requirement in important succession contexts, subject to exceptions and governing-instrument language.
New Mexico	UPC jurisdiction generally applying the 120-hour rule.
New York	Express 120-hour rule under EPTL § 2-1.6, covering numerous governing instruments and subject to enumerated exceptions.
North Carolina	Express 120-hour requirement, generally requiring clear and convincing evidence of survival; statutory exceptions include governing instruments that provide their own simultaneous-death or survivorship terms.
North Dakota	UPC jurisdiction generally using the 120-hour rule.
Ohio	Ohio has modern Uniform Simultaneous Death Act provisions and generally uses a 120-hour standard.
Oklahoma	Has statutory simultaneous-death provisions; Oklahoma-specific rules and governing documents should be reviewed.
Oregon	Uses modern simultaneous-death/survivorship concepts, including the 120-hour approach in covered circumstances.
Pennsylvania	Pennsylvania has statutory rules addressing simultaneous deaths and survivorship; estate planners should coordinate those defaults with express survivorship provisions in wills, trusts and beneficiary designations.
Rhode Island	Has simultaneous-death legislation; check Rhode Island’s current statute and the governing instrument for the transfer involved.
South Carolina	UPC-influenced probate law generally uses a 120-hour survival requirement in major succession contexts.
South Dakota	UPC-style jurisdiction generally applying 120-hour survivorship principles.
Tennessee	Tennessee has statutory simultaneous-death/survivorship rules. Estate plans should expressly address common-disaster and survivorship issues rather than relying solely on statutory defaults.
Texas	Texas expressly uses a 120-hour rule for important probate transfers. A devisee who does not survive the testator by 120 hours is generally treated as predeceasing the testator unless qualifying will language provides otherwise.
Utah	UPC jurisdiction generally applying the 120-hour rule.
Vermont	Has statutory survivorship/simultaneous-death rules; Vermont-specific provisions should be checked.
Virginia	Express 120-hour rule under its Uniform Simultaneous Death Act, generally requiring clear and convincing evidence of survival.
Washington	Has statutory survivorship/simultaneous-death provisions; Washington-specific requirements should be reviewed for the particular asset.
West Virginia	Has statutory simultaneous-death rules; applicable provisions and governing documents should be checked.
Wisconsin	Uses statutory simultaneous-death/survivorship provisions influenced by modern uniform-law principles.
Wyoming	Has statutory survivorship/simultaneous-death provisions; Wyoming-specific treatment should be reviewed for the particular transfer.

The District of Columbia also has simultaneous-death legislation. The Uniform Law Commission continues to identify the Uniform Simultaneous Death Act as a current uniform act built around the 120-hour default.

The Most Important Exception: Your Estate Plan Can Often Say Something Else

This may be the most important estate-planning point in the entire discussion.

The statutory rule is generally a default—not necessarily the final word.

A properly drafted will or trust can establish its own survivorship requirement.

For example:

“A beneficiary must survive me by thirty days to receive a distribution under this instrument.”

Now the estate plan has a 30-day survivorship period, not merely five days, assuming the provision is valid and applicable.

Virginia expressly recognizes exceptions where a governing instrument addresses simultaneous/common-disaster deaths or establishes its own survivorship requirement.

North Carolina contains similar exceptions.

New York does as well.

That raises an interesting question.

Why Would My Will Require 30 Days Instead of Five?

Consider spouses with reciprocal estate plans.

Husband dies.

Wife survives for six days but never regains consciousness.

Under a five-day statutory rule, Wife may have survived long enough to inherit.

That could mean assets move into Wife’s estate only to be distributed again shortly thereafter.

A 30-day survivorship clause could avoid that.

Some estate plans use 30 days.

Others use 60 days.

Some use 90 days.

The appropriate period depends upon the family, tax planning, beneficiary structure and objectives of the estate plan.

Longer is not automatically better.

The “Titanic Clause”

Estate-planning attorneys sometimes refer informally to a “Titanic clause” or common-disaster clause.

The name comes from the obvious historical problem: husbands and wives traveling together could die in the same disaster without anyone knowing who died first.

A modern clause might specify exactly how the estate should be administered if spouses die simultaneously or under circumstances making the order of death uncertain.

For example, Husband’s will might provide:

My spouse shall be deemed to have predeceased me.

Wife’s will might contain the mirror provision:

My spouse shall be deemed to have predeceased me.

That is logically impossible in the real world.

In estate planning, however, it can be extremely useful.

Each spouse’s estate can then be distributed independently according to that spouse’s contingent plan.

Why Blended Families Need to Pay Special Attention

Simultaneous-death planning becomes especially important in second marriages.

Suppose John has two children from his first marriage.

His new wife, Karen, has three children from hers.

John’s will says:

Everything to Karen. If Karen does not survive me, everything to my children.

Karen’s will says:

Everything to John. If John does not survive me, everything to my children.

Now they are in the same accident.

John dies at 9:00 p.m.

Karen dies at 4:00 a.m.

Without an appropriate survivorship rule, John’s assets could potentially move to Karen and ultimately to Karen’s children.

John’s children could receive nothing.

That may be the exact opposite of John’s intention.

A well-designed survivorship provision can dramatically reduce this risk.

What About Estate and Inheritance Taxes?

Here is where things become even more complicated.

The identity of the person deemed to survive can affect:

federal estate-tax planning;
marital deductions;
state estate taxes;
state inheritance taxes;
generation-skipping transfer planning;
basis issues;
trust funding; and
which estate ultimately owns a particular asset.

Pennsylvania provides a good illustration of why state tax law can matter.

Pennsylvania imposes inheritance tax based in significant part upon the relationship between the decedent and beneficiary.

If an asset moves from one spouse to another and then from the surviving spouse to children, the tax analysis may differ from an asset treated as passing directly under the first spouse’s estate plan.

For larger estates, simultaneous-death clauses therefore should not be drafted in isolation.

They should be coordinated with the estate’s overall tax strategy.

What Happens If Nobody Knows Who Died First?

This is the classic simultaneous-death problem.

Two people are found deceased after a house fire.

Medical evidence cannot establish who survived whom.

Under modern statutes, the law does not necessarily force the family into an expensive battle over forensic estimates.

Instead, the statute provides a rule for determining how the property will be distributed.

Some modern statutes require survivorship to be established by clear and convincing evidence.

Virginia expressly uses that standard.

North Carolina does too.

New York likewise requires clear and convincing evidence under its 120-hour statute.

So the question may not simply be:

“Can we prove Mom died after Dad?”

It may instead be:

“Can we establish by the required evidentiary standard that Mom survived Dad for the statutory period?”

Those are very different questions.

The Rule Can Apply Beyond Married Couples

Do not let the classic husband-and-wife example obscure the broader issue.

Simultaneous-death rules can matter whenever inheritance depends upon survivorship.

That can include:

parent and child;
siblings;
unmarried partners;
grandparents and grandchildren;
business partners;
trust beneficiaries;
joint account owners;
joint tenants;
life-insurance beneficiaries;
retirement-account beneficiaries; and
TOD/POD beneficiaries.

Imagine a mother names her adult daughter as primary beneficiary of a $900,000 IRA and her grandchildren as contingent beneficiaries.

Mother and daughter die in the same accident.

The survival rules could determine whether the IRA passes directly to the grandchildren or instead becomes associated with the daughter’s estate or beneficiary structure.

That can have significant administrative and potentially tax consequences.

Your Will Doesn’t Control Everything

One of the biggest estate-planning mistakes is assuming that a simultaneous-death clause in a will solves the problem everywhere.

Not necessarily.

You may have:

a will;
revocable trust;
irrevocable trust;
IRA;
401(k);
life-insurance policy;
TOD brokerage account;
POD bank account;
jointly titled residence; and
jointly owned investment property.

Each may be governed by different documents, contractual terms and statutory provisions.

A beautiful 30-day survivorship clause in your will does little good if most of your wealth passes outside the will under beneficiary designations that produce a different result.

The entire estate plan needs to work together.

A Five-Day Survival Rule Is Not a Medical Definition of Death

This point deserves emphasis.

The 120-hour rule does not mean the second person was legally “dead” during those five days.

Suppose Wife dies Monday.

Husband remains alive until Thursday.

Husband was alive Tuesday and Wednesday.

His doctors treated him.

His agent under a health-care power of attorney may have made decisions for him.

His legal rights continued while he was alive.

The survivorship statute merely creates a rule for determining certain property rights after death.

It does not rewrite medical history.

Can You Override the Statute?

Often, yes.

Modern simultaneous-death statutes commonly recognize properly drafted governing-instrument provisions.

That gives estate planners considerable flexibility.

A document might say:

Five days

Ten days

Thirty days

Sixty days

or another period.

It might also establish special rules specifically for spouses.

But this should not be done casually.

A survivorship provision can interact with tax provisions, marital trusts, disclaimers, powers of appointment and other sophisticated planning techniques.

Maryland Provides a Great Example of Why Estate Plans Need Updating

Estate planning law does not stand still.

In 2026, Maryland enacted legislation modernizing its Uniform Simultaneous Death Act. The legislation provides, among other things, that a surviving individual who does not survive another individual’s death for at least 120 hours is deemed to have predeceased the other individual for covered inheritance purposes.

That is exactly why an estate plan drafted ten or twenty years ago should not simply be placed in a drawer forever.

Statutes change.

Families change.

Assets change.

Beneficiaries change.

And the interaction between the documents and default law can change with them.

The $2 Million Example

Consider Mark and Jennifer.

They each have children from previous marriages.

Mark owns:

$800,000 brokerage account;
$600,000 retirement account; and
half of a $1.2 million jointly owned home.

Jennifer has approximately $1 million of separate assets.

They are involved in the same accident.

Mark dies immediately.

Jennifer survives for two days.

If their documents simply leave everything outright to the surviving spouse without carefully coordinated survivorship provisions, the ultimate destination of Mark’s wealth could depend heavily upon the governing instruments and applicable law.

Now imagine Mark’s will instead provides:

Jennifer must survive Mark by 30 days.

Mark’s trust contains the same requirement.

His beneficiary designations have been coordinated with the plan.

Now Jennifer’s two-day survival does not necessarily redirect Mark’s estate plan.

Mark’s assets can instead move according to his contingent instructions—perhaps into protected trusts for his children.

One paragraph could determine the destination of more than $1 million.

That is why “boilerplate” isn’t always boilerplate.

Questions to Ask When Reviewing Your Estate Plan

When you review your will or trust, ask:

How long must my spouse survive me?
How long must my children survive me?
What happens if my spouse and I die in the same accident?
What happens if nobody can determine who died first?
Do my will and trust use the same survivorship period?
Do my beneficiary designations coordinate with those provisions?
What happens to jointly owned property?
Does the answer change if my spouse survives for several days but never regains consciousness?
Would the result accidentally disinherit my children from a previous relationship?
Could the survivorship provision create an unintended estate- or inheritance-tax result?

If you cannot answer those questions after reading your estate plan, it may be time for a review.

The Bottom Line: Sometimes Five Days Determines Who Gets Everything

Simultaneous-death laws solve an obscure but potentially enormous estate-planning problem.

The modern Uniform Simultaneous Death Act is built around a straightforward default concept: 120 hours of survival.

But the national picture is not completely uniform.

Different states have different statutory histories, formulations, exceptions and interactions with wills, trusts, joint ownership and beneficiary-designated assets. And in many jurisdictions, a carefully drafted governing instrument can replace the statutory default with a different survivorship rule.

That means the better estate-planning question isn’t merely:

“What happens if my spouse and I die at exactly the same time?”

It is:

“What happens if we die five minutes, five hours, five days—or five weeks—apart?”

For most families, that possibility is remote.

But estate planning exists precisely because remote possibilities can have enormous consequences.

And when two people die close together, a seemingly insignificant clause buried near the back of a will or trust can determine whether property goes to a spouse’s estate, children, stepchildren, grandchildren, siblings—or somewhere nobody intended.

Estate-planning takeaway: Review your will, trust, joint ownership and beneficiary designations together. Your state’s simultaneous-death statute provides a safety net. A thoughtfully drafted estate plan determines whether that safety net actually produces the result you want.

This article provides general educational information about simultaneous-death and survivorship laws throughout the United States. State statutes differ and can change, and special rules may apply to particular wills, trusts, retirement plans, insurance policies, jointly owned property and tax-sensitive estate plans. Legal advice should be based on the law in effect at the time of death and the actual governing documents.