Yes, grandparents can open a bank account for a grandchild, but the rules depend on the child's age and your relationship to the bank

Grandparents can open a bank account for a grandchild in most cases, but the account structure and your role in it differ based on whether the child is a minor or adult. If the grandchild is under 18, you will typically open a custodial account (also called a minor account or guardian account) where you act as the custodian—you control the money until the child reaches the age of majority, usually 18 or 21 depending on your state. If the grandchild is already an adult, they open their own account; you cannot open one in their name without their presence and consent.

Banks do not require you to be a parent to open a custodial account. You will need to provide the child's Social Security number, proof of your identity, and proof of your relationship to the child (birth certificate, custody papers, or guardianship documents if you have legal custody). Some banks ask for the child's birth certificate; others do not. Call ahead to confirm what your bank requires, because requirements vary by institution.

Key Takeaways

  • Grandparents can open a custodial account for a minor grandchild using the child's Social Security number and a birth certificate or custody documents.
  • You will be the custodian and control the account until the child reaches 18 or 21, at which point the account converts to their name and they take full control.
  • The child's Social Security number is required, and the account will be reported on their tax return if it earns interest or investment income above a certain threshold.
  • Some banks allow you to open an account online or by mail if you have a customer relationship; others require all parties to visit in person.
  • If you do not have legal custody or guardianship, the child's parent may need to consent or co-sign, depending on the bank's policy.

What documents you need to bring or provide

To open a custodial account for a grandchild, bring or upload your government-issued photo ID (driver's license or passport), proof of your Social Security number (tax return, W-2, or Social Security card), and the grandchild's Social Security number. You will also need proof of the child's identity and age—a birth certificate is the most common document, though some banks accept a state ID or passport if the child is older.

If you do not have legal custody or guardianship of the grandchild, the bank may ask for written consent from the child's parent or legal guardian. This protects the bank from disputes later. If you do have legal custody or guardianship, bring those court documents; they establish your authority to open the account without parental consent. Call your bank before you visit to confirm the exact list, because requirements differ between institutions and sometimes between branches of the same bank.

How the account works while the child is a minor

Once the account is open, you are the sole signer and decision-maker. You can deposit money, withdraw funds, and manage the account however you choose. The child's name appears on the account, but they cannot access it, write checks, or make withdrawals without your permission—even if they know the PIN or password. The account is held in a format like "Grandparent Name, Custodian for Grandchild Name" or "Grandchild Name, UTMA/UGMA" (Uniform Transfers to Minors Act or Uniform Gifts to Minors Act, depending on your state).

Money in the account belongs to the child, not to you, even though you control it. This matters for taxes and for what happens if you face legal trouble. If the account earns interest or investment income above a certain amount (the threshold varies by year and is set by the IRS), you will file a tax return reporting that income in the child's name. The child may owe taxes on the earnings, though the rate is often lower than yours because of their lower income bracket.

What happens when the grandchild turns 18 or 21

When the child reaches the age of majority—18 in most states, 21 in a few—the account automatically converts to their name and they gain full control. You no longer have access unless they add you as an authorized user, which they can do but are not required to do. Some banks send a notice before the conversion; others do not. If you want to know the exact date and process for your bank, ask when you open the account.

This is an important moment to discuss with the grandchild if you have that relationship. Some grandparents use the conversion as a teaching opportunity about money management. Others set expectations about what the money is for—college, a car, emergency savings. The child is not legally bound by those conversations, but having them early can prevent misunderstandings later.

Whether you need the parent's permission

If you have legal custody or guardianship of the grandchild, you do not need the parent's permission. Your court documents give you the authority to open the account on your own. If you do not have legal custody, the answer depends on the bank and on your state's law. Some banks require written consent from the child's parent or legal guardian; others do not. A few banks will open the account only if a parent is present or co-signs.

The safest approach is to ask the parent first, even if the bank does not require it. This prevents conflict later and makes it clear that you are not trying to hide the account or undermine the parent's authority. If the parent objects, most banks will not open the account. If the parent consents but the bank still requires their signature, the parent can usually provide it by mail or electronically.

Custodial accounts versus other options

A custodial account is the most common way for grandparents to save for grandchildren, but it is not the only option. A 529 college savings plan is a tax-advantaged account designed specifically for education expenses; you can open one as the account owner and name the grandchild as the beneficiary. A Coverdell Education Savings Account works similarly but has lower contribution limits. A regular savings account in your own name, with the understanding that you are saving for the grandchild, is also an option—though it offers no tax advantages and the money is legally yours, not the child's.

Each option has different tax treatment, contribution limits, and rules about what the money can be used for. If your goal is general savings for any purpose, a custodial account is usually the simplest. If you are saving specifically for college, a 529 plan often makes more sense because of the tax benefits. Talk to your bank or a tax professional about which option fits your situation.

What happens if you pass away before the child turns 18

If you die while you are the custodian, the account does not disappear—it passes to the child's other parent or legal guardian, who becomes the new custodian. If there is no other guardian, the court will appoint one, and that person takes over the account. The money remains in the child's name and continues to grow. You can name a backup custodian in your will to make the transition smoother, though not all banks honor this request—some require a court order.

This is worth planning for if you are opening a large account or if you are the child's primary caregiver. Talk to an estate attorney about how to structure your will so that your wishes about the account are clear. You can also discuss it with the bank when you open the account; some banks have forms for naming a successor custodian.

Frequently Asked Questions

Can I open a custodial account if I do not have the child's Social Security number?

No. Banks are required by federal law to collect the child's Social Security number to open any account in their name. If the child does not have a Social Security number yet, you can apply for one through the Social Security Administration before opening the account. The process takes a few weeks.

Can I withdraw money from the account for my own expenses?

Legally, no. The money in a custodial account belongs to the child, not to you, even though you control it. Withdrawing money for your own use is considered a breach of your duty as custodian and can have tax and legal consequences. Money should be used only for the child's benefit—education, medical care, living expenses, or savings for their future.

What if the child's parent wants to close the account?

If you have legal custody or guardianship, the parent cannot close the account without your permission. If you do not have legal custody, the parent may have the right to close it or access it, depending on your state's law and the bank's policy. This is another reason to discuss the account with the parent beforehand and, if possible, get their consent in writing.

Do I have to report the account to the IRS?

You do not report the account itself, but if it earns income above a certain threshold (the amount changes yearly), you will file a tax return reporting that income in the child's name. The child may owe taxes on the earnings. Interest earned on savings accounts and investment income are both reportable. Ask your bank or a tax professional about the current threshold and whether your account will trigger a filing requirement.

Can I open a custodial account online, or do I have to visit the bank in person?

Some banks allow you to open a custodial account online if you are already a customer; others require at least one visit in person. A few banks require the child to be present as well. Call your bank or check their website to see what they require. If you bank online only, ask whether they offer custodial accounts and what their process is.