How to Adopt an Adult in Illinois
Reviewed by DocDraft Legal Team · Illinois · Last updated October 7, 2026
Two years under the same roof, or a place on a list of 15 family relationships: in Illinois one of those is the price of admission to an adult adoption. The proceeding itself is a circuit court judgment that creates a permanent legal parent and child relationship between two adults, with the next of kin standing and inheritance consequences that come with it. The Adoption Act opens it only through those two gateways (750 ILCS 50/3). Either the adult has lived in the home of the people intending to adopt for more than 2 years continuously, at any point before filing, or those people are related to the adult within one of the degrees listed in 750 ILCS 50/1, which run from parent and grandparent through uncle, aunt and second cousin. An adult who clears neither gateway cannot be adopted in Illinois. There is no disability category and no foster care category. Past that gate, consent is simple. Only the adult being adopted consents (750 ILCS 50/8(e)). That adult's own husband or wife does not consent, and the birth parents neither consent nor become parties. What Illinois demands instead sits on the adopting side. If you are married or in a civil union and have not lived separate and apart for 12 months or longer, your spouse or partner must be a party and the adoption must be by both of you jointly (750 ILCS 50/2.A(a)). You must also have resided in Illinois continuously for at least 6 months before you file. In Cook County the case goes to the County Division, not Domestic Relations. Attorney review of your petition is available through DocDraft.
Find out where you stand in Illinois
Who are you hoping to adopt?
DocDraft provides document preparation, not legal advice.
Who can be adopted as an adult in Illinois?
Only an adult who clears one of two gateways in 750 ILCS 50/3. Either the adult lived in the home of the people intending to adopt for more than 2 years continuously at some point before the case begins, or those people are related to the adult within a degree listed in 750 ILCS 50/1.
Who must consent to an adult adoption in Illinois?
Only the adult being adopted. 750 ILCS 50/8(e) provides that in the case of the adoption of an adult, only the consent of such adult shall be required. The adult's spouse does not consent, and 750 ILCS 50/8(a)(4) removes the consent of the parent of an adult sought to be adopted.
Which court hears an adult adoption in Illinois?
The circuit court. Illinois has a unified trial court with no separate probate or family court, and 750 ILCS 50/4 allows the proceeding to be commenced in any county in the state. In Cook County the case is assigned to the County Division rather than the Domestic Relations Division.
How long must someone live in Illinois before filing an adult adoption?
At least 6 months. Under 750 ILCS 50/2.A the petitioner must have resided in Illinois continuously for 6 months immediately preceding the start of the proceeding, or be an armed forces member domiciled in Illinois for 90 days. A former stepparent adopting an adult is exempt under 750 ILCS 50/2.B(c).
Illinois adult adoption at a glance
Illinois treats adult adoption as a circuit court judgment that builds a permanent legal parent and child relationship between two adults, carrying the parental rights and duties and the next of kin standing that follow from it. The eligibility gate comes first here, and it is narrow. Under 750 ILCS 50/3 an adult may be adopted only if the adult lived in the home of the people intending to adopt for more than 2 years continuously, at any point before the case is commenced, or if those people are related to the adult within one of the 15 degrees defined in 750 ILCS 50/1. Past the gate, only the adult consents (750 ILCS 50/8(e)). A married petitioner's spouse or civil union partner must be a party and adopt jointly. Six months of Illinois residence is required, and no investigation is made unless the judge orders one.
Clearing the 2 year residence gateway in Cook County
The 2 year rule is the whole case here, so it is worth watching it work against real dates. You are 58 and live in Chicago. The 31 year old you took in when he was 16 stayed in your house until he was 22, six continuous years, so the residence gateway in 750 ILCS 50/3 is satisfied even though you are not related to him and Illinois offers no foster care category. You have lived in Illinois for 30 years, well clear of the 6 month rule in 750 ILCS 50/2.A. You are married and not separated, so your wife must be a party and the adoption is by both of you jointly. He alone consents. You file in the County Division. Attorney review of the petition is available through DocDraft.
Relevant Laws
750 ILCS 50/3 (who may be adopted, including the adult gateways)
The single provision that gates adult adoption in Illinois. An adult may be adopted only if the adult has resided in the home of the persons intending to adopt for more than 2 years continuously at any time preceding the proceeding, or those persons are related within a degree set out in Section 1.
750 ILCS 50/8 (consents to adoption)
Subsection (e) provides that in the case of the adoption of an adult, only the consent of such adult shall be required. Subsection (a)(4) lists being the parent of an adult sought to be adopted among the findings that remove an otherwise required consent or surrender.
750 ILCS 50/2 (who may adopt, spousal joinder and the 6 month residency)
Paragraph A imposes 6 months of continuous Illinois residence and requires a married petitioner's spouse or civil union partner to be a party so the adoption is joint. Paragraph A(c) and paragraph B(c) exempt a former stepparent adopting an adult from joinder and from residency.
750 ILCS 50/6 (investigation, and the express adult carve out)
Paragraph A sets the investigation and fingerprint based criminal background check for the adoption of a child other than a related child. Paragraph D provides that the investigation shall not be made when the petition seeks to adopt a related child or an adult unless the court so orders.
755 ILCS 5/2-4 (Probate Act, adopted child and inheritance)
Subsection (a) treats an adopted child as a descendant of the adopting parent for inheritance from that parent and from that parent's kindred, unless the person was adopted after turning 18 and never resided with the adopting parent before 18, in which case the kindred inheritance is withheld.
Regional Variances
Illinois adult adoption rules at a glance
Who may be adopted
Category restricted, with two gateways and no general route. The adult lived in the home of the people intending to adopt more than 2 years continuously at any time before the case begins, or those people are related within a listed degree (750 ILCS 50/3). No disability or foster care category exists.
The kinship degrees
Gateway two borrows the degree list in 750 ILCS 50/1.B: parent, grand-parent, great-grandparent, brother, sister, step-parent, step-grandparent, step-brother, step-sister, uncle, aunt, great-uncle, great-aunt, first cousin or second cousin, by blood, marriage, adoption or civil union.
Who counts as an adult
750 ILCS 50/1.A-5 defines an adult, for a petition under Section 3, as a person who is 18 years old or older. The Act separately defines a child as a person under legal age, so provisions written about a child do not reach an adult adoptee.
Consent of the adult being adopted
Required and exclusive. 750 ILCS 50/8(e) provides that in the case of the adoption of an adult, only the consent of such adult shall be required. Illinois sets no substitute consenter for an adult who cannot consent, so no alternative route appears in the text.
Consent of the adult's spouse
Not required. Illinois has no provision addressing the spouse of the person being adopted, and the word only in 750 ILCS 50/8(e) excludes any further consent. This is an express statutory exclusion rather than mere silence in the Act.
The adopting person's spouse
Joinder, not consent. A spouse or civil union partner must be a party and the adoption must be by both jointly, unless they have lived separate and apart 12 months or longer (750 ILCS 50/2.A(a)). A former stepparent adopting an adult is exempt (750 ILCS 50/2.A(c)).
Birth parents
No consent and no notice. 750 ILCS 50/8(a)(4) covers the parent of an adult sought to be adopted, and 750 ILCS 50/5.C limits an adult petition to paragraph B items (a), (b) and (i), omitting (f), which would name the parents and make them parties defendant.
Age differential
None. Illinois sets no minimum number of years between the petitioner and the adult being adopted, and does not require the adult to be younger. The only age rules are that the adoptee be 18 or older and the petitioner be of legal age, or a minor by leave of court on good cause shown.
Court and venue
The circuit court, a unified trial court with no probate or family court. 750 ILCS 50/4 allows the proceeding to be commenced in any county in the state, so there is no county residency requirement to satisfy on top of the statewide one.
Cook County division
Cook County divides its circuit court, and adoption sits in the County Division at the Richard J. Daley Center, Room 1202, not the Domestic Relations Division. The Clerk's division page and the court's own case numbering order both place adoption there. Other Illinois counties are not divided this way.
Residency
6 months of continuous Illinois residence immediately preceding the commencement of the proceeding, or 90 days of Illinois domicile for a member of the armed forces (750 ILCS 50/2.A). It applies to the petitioner, not the adult. Length of residence is mandatory pleading content under 750 ILCS 50/5.C.
Filing fee
No statewide figure. Under 705 ILCS 105/27.1b the county board sets circuit clerk fees by ordinance within statutory caps, and the schedule a case falls into is set by the Supreme Court. The same section bars any fee beyond the scheduled filing fee in an adoption proceeding.
Investigation
Expressly not made for an adult unless the court orders it (750 ILCS 50/6.D). Because the fingerprint based criminal background check is a component of that investigation under 750 ILCS 50/6.A, it is carved out by the same sentence. The court may appoint a person it deems competent if it does order one.
Name change
Granted in the same judgment, and required pleading rather than an optional prayer. 750 ILCS 50/5.B(i) requires the petition to state the name to be given the child or adult, and 750 ILCS 50/5.C lists that item among the three an adult petition must contain.
Inheritance
750 ILCS 50/17 relieves the birth parents of responsibility and strips their rights, preserving them for a parent who is also a petitioner. 755 ILCS 5/2-4(a) withholds kindred inheritance where the person was adopted after 18 and never resided with the adopting parent before 18.
Statewide forms
No statewide adult adoption form was located, so the petition is drafted to the statute. The required content is fixed by 750 ILCS 50/5.B(a), (b) and (i) and 750 ILCS 50/5.C, and 750 ILCS 50/5.D requires the petitioners to verify it. Some circuit clerks publish local packets.
Suggested Compliance Checklist
Establish which 750 ILCS 50/3 gateway applies
Before you draft anything days after startingPin down either more than 2 years of continuous residence by the adult in your home at some point before filing, with the dates, or a kinship link inside the degrees listed in 750 ILCS 50/1.B. An adult who clears neither gateway cannot be adopted in Illinois.
Verify your 6 month Illinois residency
Before you commence the proceeding days after startingConfirm continuous Illinois residence for at least 6 months immediately preceding commencement, or 90 days of Illinois domicile as an armed forces member (750 ILCS 50/2.A). Check whether the former stepparent exemption in 750 ILCS 50/2.B(c) applies to you instead.
Settle your spouse's role as a party
Before the petition is drafted days after startingIf you are married or in a civil union and have not lived separate and apart 12 months or longer, your spouse or partner is a party and the adoption is joint under 750 ILCS 50/2.A(a). Confirm whether the former stepparent carve out in 750 ILCS 50/2.A(c) removes that.
Draft the verified petition to adopt an adult
First document to prepare days after startingInclude the three items 750 ILCS 50/5.C requires from paragraph B, your names, your Illinois residence and its length, and the name to be given the adult, plus the adult's name, place and date of birth and sex. Attorney review of the petition is available through DocDraft.
Prepare the adult's written consent
With the petition days after starting750 ILCS 50/8(e) makes the adult's consent the only consent required, and 750 ILCS 50/14(f-1) ties the timing of the judgment to it. Do not prepare a consent for the adult's spouse or for the birth parents; Illinois asks for neither.
File in the circuit court for your chosen county
When the papers are signed and verified days after starting750 ILCS 50/4 permits commencement in any county in Illinois. Ask the clerk for the filing fee, which the county board sets under 705 ILCS 105/27.1b. If you file in Cook County, present the petition to the County Division rather than Domestic Relations.
Confirm the inheritance position before the judgment
Before the judgment is entered days after startingCheck whether the adult resided with you before turning 18. Under 755 ILCS 5/2-4(a) a person adopted after 18 who never did is a child but not a descendant, and so does not inherit from your lineal or collateral kindred. That test differs from the 750 ILCS 50/3 gateway test.
| Task | Description | Document | Days after starting |
|---|---|---|---|
| Establish which 750 ILCS 50/3 gateway applies | Pin down either more than 2 years of continuous residence by the adult in your home at some point before filing, with the dates, or a kinship link inside the degrees listed in 750 ILCS 50/1.B. An adult who clears neither gateway cannot be adopted in Illinois. | - | Before you draft anything |
| Verify your 6 month Illinois residency | Confirm continuous Illinois residence for at least 6 months immediately preceding commencement, or 90 days of Illinois domicile as an armed forces member (750 ILCS 50/2.A). Check whether the former stepparent exemption in 750 ILCS 50/2.B(c) applies to you instead. | - | Before you commence the proceeding |
| Settle your spouse's role as a party | If you are married or in a civil union and have not lived separate and apart 12 months or longer, your spouse or partner is a party and the adoption is joint under 750 ILCS 50/2.A(a). Confirm whether the former stepparent carve out in 750 ILCS 50/2.A(c) removes that. | - | Before the petition is drafted |
| Draft the verified petition to adopt an adult | Include the three items 750 ILCS 50/5.C requires from paragraph B, your names, your Illinois residence and its length, and the name to be given the adult, plus the adult's name, place and date of birth and sex. Attorney review of the petition is available through DocDraft. | - | First document to prepare |
| Prepare the adult's written consent | 750 ILCS 50/8(e) makes the adult's consent the only consent required, and 750 ILCS 50/14(f-1) ties the timing of the judgment to it. Do not prepare a consent for the adult's spouse or for the birth parents; Illinois asks for neither. | - | With the petition |
| File in the circuit court for your chosen county | 750 ILCS 50/4 permits commencement in any county in Illinois. Ask the clerk for the filing fee, which the county board sets under 705 ILCS 105/27.1b. If you file in Cook County, present the petition to the County Division rather than Domestic Relations. | - | When the papers are signed and verified |
| Confirm the inheritance position before the judgment | Check whether the adult resided with you before turning 18. Under 755 ILCS 5/2-4(a) a person adopted after 18 who never did is a child but not a descendant, and so does not inherit from your lineal or collateral kindred. That test differs from the 750 ILCS 50/3 gateway test. | - | Before the judgment is entered |
Frequently Asked Questions
Other Illinois guides
Adverse Possession in Illinois: Which of the Clocks Is Yours, Twenty Years or Seven
Asset Protection Planning in Illinois (2026)
Dealing With Debt Collectors in Illinois (2026)
Expunging a Criminal Record in Illinois (2026)
Filing a Workplace Harassment Complaint in Illinois
Filing Chapter 7 Bankruptcy in Illinois (2026)
Ready to Draft Your Document?
Get AI-powered legal documents with attorney review included. Plans start at $39.99/mo.
Get Started