What Is a Will and Why Might You Need One?

A will is a written plan for what happens to your things after you die. In it, you say who gets your property, who's in charge of handing it out and who you'd want to raise your kids if you can't. If you have children, a home, savings or people you want to protect, a will is one of the most useful documents you can sign.

1. What a will does

A will, formally called a last will and testament, does three main jobs:

Says who gets what. You can leave money, a car, a home or a favorite watch to the people or charities you choose.
Names your executor. Your executor is the person who handles your estate. They pay your final bills and hand out what's left.
Names a guardian for your kids. A guardian is the adult who raises your children if both parents are gone.

The person making the will is called the testator. The people who receive gifts are your beneficiaries.

A judge makes your will official after you die. This happens in probate, the court process that checks the will was signed the right way and puts your executor in charge. A judge also has to approve your choice of guardian, and usually follows your wishes unless that person isn't a good fit for your child.

2. What a will doesn't control

A will covers the things in your name alone, like your car, a bank account with no one named on it, or your share of a home that isn't held jointly.

A will can't change who gets:

Retirement accounts and life insurance. Your 401(k), IRA and life insurance go to whoever you named on the beneficiary form.
Payable-on-death (POD) or transfer-on-death (TOD) accounts. These go straight to the person named on the account.
Jointly owned property with survivorship. A joint account or a home owned this way goes to the other owner.
Property in a trust. A trust is a legal arrangement that holds property for someone and sets rules for using it. The trust's rules control it.

A will also doesn't skip probate; named beneficiaries, joint accounts and trusts do. And a will doesn't erase your debts, which get paid from your estate first.

That's why your beneficiary forms matter as much as your will, so check them every few years.

3. Who can make a will

In New York, anyone 18 or older who is "of sound mind and memory" can make a will. Most states use a similar rule.

Being of sound mind is called capacity. It means you're clear-headed enough to understand what you own, who your family is and what you're signing.

A will can be challenged in court if you didn't have capacity, or if someone pressured you into it. The best protection is simple: sign while you're well, with people you trust around you.

4. The key parts of a will

Most wills include these pieces:

Specific gifts. "My car goes to my nephew, Leo."
A residuary clause. This says who gets everything else, the "residue," after specific gifts and bills. Without it, property you forgot to mention may pass under state law instead of your wishes.
Contingent beneficiaries. A contingent beneficiary is a backup who gets a gift if your first choice dies before you.
Your executor and a backup. Pick someone organized and willing, and talk to them first.
A guardian and a backup for children under 18.

You can name two executors to serve together, but they'll have to sign everything together. One organized person plus a backup is often easier.

Leaving money to kids. A child under 18 can't manage a large inheritance directly. A trust lets you pick a grown-up to manage it and say when your child gets it, such as at age 25.

5. How to sign a will in New York

A will only counts if you sign it the right way. These steps are called the execution formalities, and every state has its own. Here are New York's:

Sign at the very end of the will. Anything written below your signature doesn't count, other than the witnesses' part.
Have at least two witnesses. They must watch you sign, or hear you say the signature is yours.
Tell the witnesses it's your will. Saying "This is my will" is enough.
The witnesses sign too. Each one signs and usually adds their home address. Both witnesses must sign within the same 30-day period.

Pick witnesses who inherit nothing. In New York, if a witness also gets a gift in the will, that gift can be cancelled unless two other witnesses who get nothing also signed.

Ask for a self-proving affidavit. A self-proving affidavit is a short sworn statement your witnesses sign in front of a notary. It lets the court accept the will without calling the witnesses to testify years later.

A signing example. Marcus prints the will his lawyer drafted and signs at the bottom of the last page while his neighbor Ana and his coworker Ben watch. He tells them, "This is my will." Ana and Ben sign right under his name, add their addresses, and then sign a self-proving affidavit in front of a notary. Neither of them inherits anything, so Marcus has done it right.

6. Handwritten and phone wills in New York

Handwritten wills. In New York, a handwritten will with no witnesses doesn't count for most people. The only exceptions are people serving in the U.S. armed forces during a war or armed conflict (and people serving with them), and mariners at sea. Even those wills expire: a service member's lapses one year after discharge, and a mariner's lapses three years after it was written.

Wills on a phone or computer. Right now, a will typed and saved on your phone isn't a valid will in New York. A law signed in December 2025 allows electronic wills starting June 10, 2027. They'll still need two witnesses.

Some other states accept unwitnessed handwritten wills. If you live outside New York, check your own state's rules before you rely on one.

7. A family example

Priya, 34, lives in Troy with her husband, Sam, and their 3-year-old son. Her will leaves everything to Sam and names him as executor, with her sister Asha as backup. It also names Asha as guardian if Sam can't raise their son.

But Priya's 401(k) from an old job still lists her mom, because she filled out that form before she got married. If Priya dies, the 401(k) goes by the form, not the will.

There's a twist. Federal rules for most employer 401(k) plans give a spouse the account unless the spouse signed a written waiver. So the plan may pay Sam anyway, but only after a confusing paperwork fight. The fix takes five minutes: Priya logs in and updates the beneficiary.

8. When to update your will

Review your will after big life changes: marriage, divorce, a new child, a death in the family, a move to another state or a big change in what you own.

Never write changes on your signed will. Crossing things out can cause problems in court. Instead, sign a new will, or a codicil. A codicil is a formal add-on that changes part of a will. It needs the same signing steps, with two witnesses.

If you live in New York:

Divorce. A divorce automatically cancels most gifts to your ex-spouse. This includes gifts in your will, naming your ex as executor and many beneficiary forms, such as life insurance and IRAs. Still, update every form yourself. Some employer plans follow federal rules, not New York's.
Marriage. Getting married doesn't cancel an old will. But a spouse you leave out has a right of election, which means they can claim the greater of $50,000 or one-third of your net estate (what's left after debts and costs). That claim can reach some property outside your will, like joint accounts and POD accounts.

9. Where to keep your will

Keep the signed original somewhere safe that your executor can reach, such as a fireproof home safe or your lawyer's office. A copy may not be enough. Courts usually want the original, and a missing original can make it look like you tore it up.

In New York, you can ask your county's Surrogate's Court whether it accepts wills for safekeeping. Tell your executor where the original is.

No will at all? Then state law decides who inherits, in a process called intestacy. The relatives who inherit under that law are your heirs, and your unmarried partner or best friend gets nothing. See our guide on dying without a will for how that works.

Common mistakes with wills

Skipping the witnesses. An unwitnessed will is not valid for most New Yorkers.
Using a witness who inherits. Their gift can be cancelled.
Forgetting beneficiary forms. Your will can't fix an old 401(k) or insurance form.
Leaving out a residuary clause. Anything you forgot to list may not go where you want.
Writing changes on the signed will. Use a new will or a codicil.
Hiding the original. If no one can find it, the court may treat it as if you had no will.

Frequently asked questions about wills

Do I need a lawyer to make a will?

No law requires one. But a lawyer helps you avoid signing mistakes and plan for kids, blended families or a business. Ask about the price up front, since many lawyers charge a flat fee for a simple will.

Can I use an online will template?

You can, if you follow your state's signing rules exactly. In New York, that means signing at the end in front of two witnesses who also sign. A template that's printed but never properly signed isn't a valid will.

Does a will control my 401(k)?

No. Your 401(k) goes to whoever is on its beneficiary form. If you're married, your spouse usually gets it unless they signed a form agreeing otherwise.

Does a will avoid probate?

No. A will tells the probate court what you want. To skip probate, people use beneficiary forms, joint ownership or trusts. Our guide on probate explains more.

Can I name a guardian for my pets?

Not in the same way, since the law treats pets as property. But you can leave money in a pet trust, which holds money for your pet's care and names a caregiver. New York allows pet trusts.

The bottom line

A will says who gets your things, who's in charge and who raises your kids. It doesn't control accounts with a beneficiary form, so keep those up to date too. In New York, a will only counts if you sign it at the end in front of two witnesses. Get that right, and your wishes have real legal power.

Related reading: What is an estate? · Dying without a will · What is probate? · Wills versus trusts

Official sources and further reading

Convivial Wealth education guide · General education for U.S. readers, with New York rules labeled. Not personalized legal advice. Rules are reviewed each year.

Read our full educational disclaimer.