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How to Adopt an Adult in Missouri

Reviewed by DocDraft Legal Team · Missouri · Last updated October 7, 2026

Missouri files adult adoptions in the juvenile division of the circuit court, and the order that comes out of it makes one adult the permanent legal parent of another adult, with all the inheritance and next of kin consequences a parent and child relationship carries. Section 453.010 lets any person petition to adopt another person as his or her child. No category list gates it. Nothing requires the adult to be disabled, to be a former stepchild, to have aged out of foster care, or to have known you before turning eighteen, and the chapter sets no minimum age gap. It does not even require the adult to be younger than you. Consent then collapses to a single signature. Section 453.030 provides that where the person sought to be adopted is eighteen or older, his or her written consent alone is sufficient. Birth parent consent is written for adoptees under eighteen and does not reach an adult. The adult's own husband or wife signs nothing. Your spouse is the one open variable, because section 453.010 says a living spouse may join the petition, and if that spouse stays out the court may order joinder after a hearing and dismiss the petition if the order is ignored. You pay a $50 statutory filing fee, file in the county where you live, and face no investigation, since the investigation bar in section 453.070 is keyed to a child under eighteen. Missouri publishes no statewide adult adoption form, so the petition is drafted to the statute. Attorney review of your documents is available through DocDraft.

Find out where you stand in Missouri

Who are you hoping to adopt?

DocDraft provides document preparation, not legal advice.

Who can be adopted as an adult in Missouri?

Any adult. Missouri section 453.010 lets any person petition to adopt another person as his or her child, with no list of qualifying categories, no disability requirement and no prior relationship test. The chapter sets no minimum age gap and does not require the adult to be younger than the petitioner.

Whose consent does Missouri require for an adult adoption?

Only the adult being adopted. Section 453.030 provides that where the person sought to be adopted is eighteen or older, his or her written consent alone is sufficient. Birth parent consent is written for adoptees under eighteen, and the adult's own spouse is not asked to consent at all.

Which court handles an adult adoption in Missouri?

The juvenile division of the circuit court, even though the person being adopted is an adult (section 453.010). You file in the county where the person seeking to adopt resides. That same section bars dismissal of a petition on the ground that the petitioner is not domiciled in the other listed venues.

What does it cost to file an adult adoption in Missouri?

Section 453.020 requires a $50 filing fee to accompany the petition, and that money funds the state putative father registry. Ordinary circuit court costs sit on top and are set by Supreme Court rule under section 488.012 rather than by a fixed statewide figure, so ask your clerk.

Missouri adult adoption at a glance

An adult adoption in Missouri is a court order that makes one adult the permanent legal parent of another adult, carrying every right and duty of a parent and child relationship (section 453.090). Missouri gates it behind nothing. Any person may petition to adopt another person as his or her child (section 453.010), and the chapter holds no category list, no disability route and no age gap. The consent rule is the distinctive part. An adoptee of eighteen or older signs a written consent, and that consent alone is sufficient (section 453.030). Your own husband or wife may join the petition, and the court may order that joinder after a hearing and dismiss the case if the order is refused (section 453.010). Filing goes to the juvenile division of the circuit court with $50. The file is sealed (section 453.120).

Adopting the niece you raised, when your husband wants no part of it

In Boone County a woman wants her 34 year old niece, whom she raised informally after her sister died but never held legal custody of, recognized as her daughter. Missouri asks the niece to fit no category (section 453.010). The niece signs a written consent, and because she is over eighteen that one signature is sufficient, so her own husband signs nothing and her surviving father is neither asked to consent nor served (sections 453.030 and 453.060). The aunt's husband does not want to be a second parent. Section 453.010 permits him to stay off the petition, though the judge may order him to join after a hearing. They file in the juvenile division of the Boone County circuit court with $50. Attorney review of the petition is available through DocDraft.

Relevant Laws

Mo. Rev. Stat. 453.010 (who may petition, court, venue, spousal joinder)

Provides that any person desiring to adopt another person as his or her child shall petition the juvenile division of the circuit court, and that a spouse living and competent to join may join, with the court able to order joinder after a hearing and dismiss if that order is not met.

Mo. Rev. Stat. 453.030 (consent, and the adult sufficiency rule)

Requires court approval in all cases, requires the written consent of an adoptee fourteen or older, limits birth parent consent to an adoptee under eighteen, and provides in subsection 10 that an adoptee eighteen or older gives written consent that alone is sufficient.

Mo. Rev. Stat. 453.020 (petition contents and the $50 fee)

Sets out what the petition must state, including the new name if a change is wanted, and requires the petition to include payment of a fifty dollar filing fee used to fund the putative father registry established under section 192.016.

Mo. Rev. Stat. 453.070 (investigation, keyed to a child under eighteen)

Bars entry of a decree for the adoption of a child under eighteen years of age until a full investigation including an assessment of the adoptive parents has been made. The requirement is written to a child under eighteen and does not reach an adult adoptee.

Mo. Rev. Stat. 453.090 (consequences of adoption, including for adults)

Ends the legal relationship with the natural parents except one who joins the petition, makes the adoptee the child of the adoptive parent for every purpose and capable of inheriting, and defines child in that section as a person under or over eighteen years of age.

Regional Variances

Missouri adult adoption rules at a glance

Who may be adopted

Any adult. Section 453.010 lets any person petition to adopt another person as his or her child, with no enumerated categories. Section 453.090 confirms the chapter reaches adults by defining child as a person under or over eighteen years of age.

Age relationship

No requirement at all. Missouri sets no minimum number of years between the parties and does not require the adult being adopted to be younger than the petitioner. Chapter 453 contains no age differential language in any section.

Consent of the adult being adopted

Required in writing, and sufficient standing alone once the adoptee is eighteen or older (section 453.030). A written consent is required from any adoptee fourteen or older, unless the court finds insufficient mental capacity to give it.

Consent of the adult's spouse

Not required. Missouri asks nothing of the adoptee's husband or wife, neither consent nor notice, and section 453.030 reinforces that by making the adoptee's own written consent sufficient alone.

The petitioner's spouse

Joinder is permitted rather than mandatory, but the court can compel it. Section 453.010 says a spouse living and competent to join may join, and if that spouse does not, the court may order joinder after a hearing and may dismiss the petition if the order is not complied with.

Birth parents

No consent and no notice. Section 453.030 requires birth parent consent only when the person sought to be adopted is under the age of eighteen years, and section 453.060 ties service of summons to whether a person's consent is required.

Court and venue

The juvenile division of the circuit court, for the county where the person seeking to adopt resides (section 453.010). No durational residency period applies, and the same section bars dismissal for want of domicile in the other listed venues.

Filing fee

$50 with the petition, directed to the putative father registry fund (section 453.020). Ordinary circuit court costs are additional and are set by Supreme Court rule under section 488.012, not by a fixed statewide statutory figure.

Investigation

Not reached. Section 453.070 bars a decree until a full investigation is made only for the adoption of a child under eighteen years of age. This is an age scope limit rather than an express adult exemption, so a court may still ask questions at the hearing.

Waiting period

None for an adult. The six month lawful and actual custody period in section 453.080 is written to apply only if the person sought to be adopted is a child, so it does not attach to an adult adoptee.

Name change

Available in the same decree. Section 453.080 lets the court decree a change of name according to the prayer of the petition, and section 453.020 requires the new name to be stated in the petition. Section 453.100 sends the original and new name to vital records.

Inheritance

Full effect, with no adult reduction. Section 453.090 makes the adoptee capable of inheriting from the adoptive parent as though born in lawful wedlock, including property limited expressly to heirs of the body, and defines child to include a person over eighteen.

Court records

Sealed. Section 453.120 closes adoption files and records to inspection or copying absent a court order under section 453.121, and permitting inspection without one is a class C misdemeanor. The section carries no age limit.

Forms

No statewide form. The Missouri Courts statewide form index has no adoption category and the Family Law Forms page carries no adoption petition, so the document is drafted to the section 453.020 content items. Individual circuit clerks may set local requirements.

Suggested Compliance Checklist

Confirm the statute reaches your situation

Before you draft anything days after starting

Read section 453.010 and confirm that Missouri attaches no category, age gap or prior relationship test to an adult adoption. Then read section 453.090 subsection 5, which defines child in that section to include a person over eighteen years of age.

Draft the adult's written consent

First document to prepare days after starting

Prepare a written consent for the person being adopted to sign. Section 453.030 makes it sufficient alone for an adoptee eighteen or older, and requires it to be executed no more than six months before the petition is filed. Attorney review of the consent is available through DocDraft.

Settle your spouse's position in writing

Before you draft the petition days after starting

Decide whether your husband or wife will join as a co petitioner, which makes the adoption jointly theirs under section 453.010. If they will not, be ready for the court to consider ordering joinder after a hearing and dismissing the petition if the order is not met.

Draft the petition for adoption

With the consent days after starting

Include the items section 453.020 requires: the name, sex and place of birth of the person being adopted, that person's parents' names if known to you, and the new name if a change is wanted. No statewide Missouri form exists, so check your circuit clerk's local requirements.

Verify the court and the county

Before filing days after starting

Section 453.010 directs the petition to the juvenile division of the circuit court, not a family or probate division, for the county where the person seeking to adopt resides. Call that division to confirm its filing procedure and whether it accepts electronic filing.

File the petition and pay the statutory fee

When the papers are signed days after starting

File the petition and the signed consent in the juvenile division and include the $50 payment section 453.020 requires with the petition. Ask the clerk what ordinary court costs are added, since those are set by Supreme Court rule under section 488.012 rather than fixed in the statute.

Attend the finalization hearing

On your hearing date days after starting

The court holds a hearing under section 453.080 to decide whether the adoption is finalized and whether it is fit and proper. Ask the court to decree the name change in the same order, then confirm the clerk sent the certificate of decree to vital records under section 453.100.

Frequently Asked Questions

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Dealing With Debt Collectors in Missouri (2026)

Expunging a Criminal Record in Missouri (2026)

Filing a Workplace Harassment Complaint in Missouri

Filing Chapter 7 Bankruptcy in Missouri (2026)

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