Legal Process for Adult Adoption

Most people picture adoption as something that happens to a baby or a young child. But every state in the country also allows adults to adopt other adults, and the reasons people do it are more varied than you'd expect. A stepparent who raised a spouse's child but never made it official. A foster kid who aged out of the system at 18 without ever finding a permanent family. A caregiver and the adult they've supported for decades who want their bond recognized by law. An adult who wants to lock in inheritance rights for a partner's child.

Whatever the reason, adult adoption is a real court process with real legal consequences, and it's worth understanding before you file anything.

What adult adoption actually changes

Once a judge signs off, the person being adopted becomes the legal child of the adopting parent, full stop. That means the same inheritance rights as a biological child would have, the same right to be listed as next of kin, and in most states, a new birth certificate reflecting the new parent. If the adoptee had a legal relationship with a birth parent, that relationship is usually severed, though a handful of states carve out exceptions — for example, if a stepparent is adopting and is married to one of the adoptee's birth parents, that birth parent can often keep their name on the certificate.

It's also permanent. Courts don't casually reverse adoption decrees, so this isn't something to enter into as a formality without thinking through what it means long-term.

Who's eligible

The specifics vary by state, but the general shape looks like this:

The adoptee has to be a legal adult — 18 in most states, though a few, like Alabama, set the bar at 19, and some states let 18-to-20-year-olds be adopted "as a child" under slightly different rules than full adult adoption. There's rarely an upper age limit; you can adopt someone who's 45 or 75 just as easily as someone who's 19.

The person adopting typically has to be older than the adoptee, though how much older depends on the state. Some states want a 10-year age gap. Others don't specify a gap at all, just that the adopter is an adult.

Both people need to be mentally competent to understand and agree to what they're doing, and — this is the part people sometimes miss — both have to actually consent. Unlike child adoption, where a parent or guardian consents on the child's behalf, an adult adoptee has to agree to be adopted themselves. If either person is married, most states also require that spouse's consent, since the adoption changes the legal family structure they're part of too.

The steps, roughly in order

1. Check your state's specific rules first. Family law is state law, and adult adoption statutes differ enough from one state to the next that it's worth reading your state's actual code, or talking to a family law attorney, before assuming anything from a general guide applies to you. Residency requirements, age gaps, and paperwork all shift depending on where you file.

2. File a petition with the appropriate court. This is usually a probate court or family court in the county where either person lives. The petition lays out who's adopting whom, the relationship between them, and why the adoption is being requested.

3. Gather consent. Written, signed consent from the adoptee is non-negotiable. Depending on the state and the adoptee's marital status, you may also need consent from the adoptee's spouse or the adopter's spouse.

4. Notify anyone the state requires. Some states want notice sent to certain relatives even if their consent isn't legally needed. This step exists mostly to prevent adoptions from being used to quietly cut someone out of a will or estate without their knowledge.

5. Wait out any statutory waiting period. Not every state has one, but where they exist, they give everyone involved a chance to reconsider before the hearing.

6. Attend the court hearing. This tends to be a much shorter, less invasive process than child adoption hearings — there's usually no home study, no background check, and no social worker evaluation, because the adoptee is legally capable of speaking for themselves. A judge reviews the petition and consent forms and asks a few questions to confirm both parties understand what they're agreeing to.

7. Get the final decree. Once the judge approves, the adoption is legally final. Some states will issue an amended birth certificate for the adoptee at this point; in others you may need to request one separately.

What it usually costs

Adult adoption tends to be far cheaper than adopting a child, mainly because it skips the home studies and agency involvement that drive up child-adoption costs. Filing fees alone often run somewhere in the low hundreds of dollars. If you hire an attorney to prepare the petition and represent you at the hearing, expect that to add anywhere from a few hundred to a couple thousand dollars, depending on your state and how straightforward the case is.

A few things worth thinking about beforehand

Immigration status isn't fixed by adult adoption. Unlike adopting a child under 16, adopting an adult doesn't grant the adoptee any immigration benefit or path to citizenship. If immigration status is part of why you're considering this, talk to an immigration attorney, because adult adoption won't do what you might hope it does.

Inheritance gets more complicated with existing wills. If either person already has a will or estate plan, an adoption can change who's entitled to what, sometimes in ways that conflict with what's already written down. It's worth updating estate documents alongside the adoption, not after.

Not every state recognizes the same relationships. A same-sex partner adopting an adult stepchild, for instance, may find the process smoother in some states than others, even though it's technically permitted everywhere. Local practice can differ from what the statute says on paper.

Talk to a lawyer if money or property is involved. The court process itself is simple enough that some people handle it without a lawyer, especially in states with straightforward statutes. But if there's an estate, a business, or a contested family relationship in the picture, a family law attorney can catch problems before they become expensive ones.

The bottom line

Adult adoption is one of the more low-drama corners of family law — no custody battles, no home inspections, usually no real dispute at all, since both people involved have already agreed to it before anyone files paperwork. The legal weight it carries, though, is exactly the same as adopting a child: a new, permanent parent-child relationship recognized by the state for life. If you're considering it, start by pulling up your own state's adoption statute or calling a local family law attorney, since the fine print is where the real answers live.