Illinois does not recognize common law marriage and has not since June 30, 1905. Couples cannot become legally married in Illinois simply by living together, regardless of duration or how closely the relationship resembles a traditional marriage. However, Illinois courts will recognize and dissolve common law marriages validly formed in other states under the Full Faith and Credit Clause. For couples who cohabitated in Illinois without a valid marriage, property disputes are resolved through contract law and equitable claims rather than divorce proceedings.
Key Facts: Common Law Marriage and Divorce in Illinois
| Category | Illinois Law |
|---|---|
| Common Law Marriage Status | Not recognized since June 30, 1905 |
| Out-of-State Recognition | Yes, under Full Faith and Credit Clause |
| Filing Fee (Cook County) | $388 petitioner, $251 appearance |
| Filing Fee (Other Counties) | $210-$350 depending on county |
| Residency Requirement | 90 days for at least one spouse |
| Grounds for Divorce | No-fault only (irreconcilable differences) |
| Property Division | Equitable distribution |
| Cohabitation Agreements | Legally enforceable if contract requirements met |
Does Illinois Recognize Common Law Marriage?
Illinois abolished common law marriage over 120 years ago on June 30, 1905, making it one of the earliest states to eliminate informal marriage recognition. Under 750 ILCS 5/214, a valid marriage in Illinois requires three elements: obtaining a marriage license from the county clerk, having the marriage solemnized by an authorized officiant, and registering the marriage certificate with the county. No amount of cohabitation, shared finances, or public representation as a married couple creates a legal marriage under Illinois law.
This means couples who have lived together in Illinois for 10, 20, or even 50 years are not legally married without completing these formal requirements. The practical implications are significant: unmarried partners have no automatic rights to property division, spousal support, or inheritance when the relationship ends, regardless of the relationship's duration or the couple's shared life together.
How Illinois Handles Out-of-State Common Law Marriages
Illinois courts fully recognize common law marriages validly formed in states that permit them, treating these unions identically to ceremonial marriages for divorce purposes. Under the Full Faith and Credit Clause of the U.S. Constitution, if you established a valid common law marriage in Colorado, Texas, Kansas, Iowa, Montana, Oklahoma, Rhode Island, Utah, or the District of Columbia, Illinois must honor that marriage as legally binding.
To have your out-of-state common law marriage recognized in Illinois, you must prove three elements: the state where you formed the marriage legally recognizes common law unions, you and your partner satisfied all legal requirements for common law marriage in that originating state, and the marriage has not been previously dissolved through divorce or annulment.
States That Currently Recognize Common Law Marriage (2026)
| State | Special Requirements | Notes |
|---|---|---|
| Colorado | Present yourselves publicly as married; community reputation | Revised standards in 2021 |
| Texas | Agreement to be married, cohabitation, public representation | Called "informal marriage"; both parties must be 18+ |
| Kansas | Capacity, present agreement, public holding out | Both parties must be 18+ under K.S.A. 23-2502 |
| Iowa | Continuous cohabitation, public presentation as spouses | Requires consummation |
| Montana | Consent, cohabitation, public reputation | No minimum cohabitation period |
| Oklahoma | Mental capacity, mutual agreement, cohabitation | No registration required |
| Rhode Island | Serious intent, conduct as married couple | No statutory requirements |
| Utah | Consent, cohabitation, public assumption of marital duties | Court or administrative validation available |
| District of Columbia | Intent, cohabitation, public holding out | Federal district recognition |
Filing for Divorce from an Out-of-State Common Law Marriage in Illinois
Illinois courts have full authority to dissolve common law marriages formed in other states, applying the same divorce procedures as ceremonial marriages under 750 ILCS 5/401. The filing fee in Cook County is $388 for the petitioner, while other Illinois counties charge between $210 and $350. At least one spouse must have resided in Illinois for 90 days before the court can enter a final judgment.
The critical difference is the burden of proof: couples divorcing a common law marriage must first establish that a valid marriage exists. This typically requires presenting evidence such as joint tax returns filed as married, shared bank accounts or property, testimony from witnesses who recognized the couple as married, documents from the originating state, or affidavits demonstrating all elements of common law marriage were satisfied in the state of formation.
Step-by-Step Process for Dissolving an Out-of-State Common Law Marriage in Illinois
- Gather evidence proving your common law marriage was valid in the originating state, including any Declaration of Informal Marriage (Texas) or similar documentation
- Ensure at least one spouse has been an Illinois resident for 90 days
- File a Petition for Dissolution of Marriage in the circuit court of the county where either spouse resides
- Pay the filing fee ($388 in Cook County, $210-$350 elsewhere)
- Serve your spouse with the divorce papers through sheriff service ($60 in Cook County), private process server ($50-$100), or waiver of service
- Complete financial disclosures and negotiate settlement terms
- If uncontested, attend a prove-up hearing; if contested, proceed through litigation
- Receive final judgment of dissolution
Property Division in Common Law Marriage Divorce
Illinois divides marital property using equitable distribution under 750 ILCS 5/503, meaning courts divide assets fairly but not necessarily equally. For couples divorcing a common law marriage, all property acquired after the marriage was established (in the originating state) and before the dissolution judgment is presumed marital property. This includes real estate, retirement accounts, business interests, and debts, regardless of whose name appears on the title.
Illinois courts consider 12 statutory factors when dividing property, including each spouse's contribution to acquiring or maintaining assets (homemaker contributions count equally with financial contributions), the duration of the marriage, each party's economic circumstances following divorce, tax consequences of the proposed division, and whether either spouse dissipated marital assets.
Marital vs. Non-Marital Property
| Property Type | Classification | Division Approach |
|---|---|---|
| Assets acquired during marriage | Marital property | Subject to equitable division |
| Property owned before marriage | Non-marital property | Remains with original owner |
| Inheritances received individually | Non-marital property | Stays with recipient unless commingled |
| Gifts from third parties | Non-marital property | Protected if kept separate |
| Property acquired after separation | Depends on circumstances | Court determines based on timing |
| Commingled non-marital assets | May become marital | Tracing analysis required |
Retirement accounts present particular complexity in common law marriage divorces. Both vested and non-vested pension benefits are considered marital property. Private-sector 401(k)s and pensions are divided through a Qualified Domestic Relations Order (QDRO), while state government pensions require a Qualified Illinois Domestic Relations Order (QILDRO) under 40 ILCS 5/1-119.
Rights of Unmarried Couples Who Cohabitated Only in Illinois
Couples who lived together exclusively in Illinois without a valid marriage from another state cannot file for divorce because no legal marriage exists. Illinois does not apply marital property rules to unmarried cohabitants, which creates significant legal vulnerabilities. Property titled in one partner's name is presumed to belong solely to that person, and Illinois does not recognize palimony claims for financial support between former unmarried partners.
However, the Illinois Supreme Court's 2016 decision in Blumenthal v. Brewer established important protections for unmarried cohabitants. Former partners can bring claims based on express or implied contracts and pursue equitable remedies like unjust enrichment, provided those claims stand independently and do not simply request the property division a divorcing couple would receive.
Legal Options for Unmarried Former Partners in Illinois
- Express contract claims: If you had a written or verbal agreement about sharing property or expenses, you can enforce that agreement in court
- Implied contract claims: Courts may recognize an implied agreement based on the parties' conduct and circumstances
- Unjust enrichment: If your partner was unjustly enriched at your expense (e.g., you paid for renovations on property titled solely in their name), you can pursue recovery
- Constructive trust: Courts may impose a trust on property where one party would be unjustly enriched otherwise
- Partnership or joint venture claims: If you operated a business or investment together, partnership law may apply
Cohabitation Agreements: Protecting Yourself Without Marriage
Cohabitation agreements are legally enforceable contracts between unmarried partners that establish rights and responsibilities during the relationship and upon separation. Illinois courts uphold these agreements when they meet standard contract law requirements: offer, acceptance, consideration (something of value exchanged), and mutual intent to be bound by the terms.
A comprehensive cohabitation agreement can address property ownership and division, financial responsibilities during the relationship, how to handle jointly acquired assets if the relationship ends, debt allocation, provisions for shared living expenses, and even arrangements for pets (Illinois law now allows courts to allocate companion animals in divorce under 750 ILCS 5/503(n), and similar provisions can be included in cohabitation agreements).
Key Elements of an Enforceable Illinois Cohabitation Agreement
| Element | Requirement | Best Practice |
|---|---|---|
| Written form | Not strictly required but strongly recommended | Always put the agreement in writing |
| Both parties' signatures | Essential | Sign in presence of witnesses or notary |
| Voluntary execution | No duress or coercion | Allow time for each party to review |
| Full disclosure | Material financial information shared | Exchange financial statements before signing |
| Independent counsel | Not required but advisable | Each party should consult separate attorney |
| Consideration | Something of value exchanged | Mutual promises are sufficient |
Importantly, cohabitation agreements cannot lawfully include provisions paying for sexual services, as this would render the contract unenforceable as against public policy. However, couples may agree to pool earnings, hold property separately or jointly, apply community property principles, form business partnerships, or hold property as joint tenants with right of survivorship.
Spousal Support and Maintenance Considerations
For couples divorcing a recognized common law marriage in Illinois, maintenance (spousal support) is calculated using the same guidelines as any other divorce. For combined gross incomes under $500,000, the guideline formula is 33.33% of the payor's net income minus 25% of the payee's net income, capped so the recipient does not receive more than 40% of the combined net income.
Maintenance duration depends on the marriage length under 750 ILCS 5/504. Courts multiply the years of marriage by a statutory factor ranging from 0.20 for marriages of 5 years to 0.80 for marriages of 20 years. For marriages lasting 20 years or longer, courts may order indefinite (permanent) maintenance.
Maintenance Duration Factors
| Marriage Length | Duration Multiplier | Example Duration |
|---|---|---|
| 0-5 years | 0.20 | 5-year marriage = 1 year maintenance |
| 5-6 years | 0.24 | 5.5-year marriage = 1.3 years maintenance |
| 6-7 years | 0.28 | 6.5-year marriage = 1.8 years maintenance |
| 7-8 years | 0.32 | 7.5-year marriage = 2.4 years maintenance |
| 8-9 years | 0.36 | 8.5-year marriage = 3.1 years maintenance |
| 9-10 years | 0.40 | 9.5-year marriage = 3.8 years maintenance |
| 10-11 years | 0.44 | 10.5-year marriage = 4.6 years maintenance |
| 15-16 years | 0.60 | 15.5-year marriage = 9.3 years maintenance |
| 20+ years | Court discretion | May be indefinite |
For common law marriages, determining the exact marriage date can be challenging since no ceremony or license exists. Courts typically look to when the couple began holding themselves out as married, began cohabiting with intent to be married, or when evidence shows the common law marriage was established under the originating state's law.
Child Custody and Support in Common Law Marriage Divorces
Children born to common law married couples have identical rights to those born to ceremonially married parents. Illinois uses the term "parental responsibilities" rather than custody under 750 ILCS 5/602.5, dividing decision-making authority and parenting time between parents based on the child's best interests.
Child support in Illinois follows the Income Shares Model, calculating support based on both parents' combined net income and dividing the obligation proportionally. When each parent has 146 or more overnights per year, a shared-parenting adjustment with a 1.5 multiplier and cross-credit applies. Illinois updates its basic support obligation schedule annually, most recently in March 2025.
Fee Waivers for Low-Income Filers
If you cannot afford divorce filing fees, Illinois Supreme Court Rule 298 allows you to apply for a fee waiver if your household income falls at or below 125% of the federal poverty guidelines (approximately $18,500 annually for a single person in 2026). To obtain a waiver, you must complete an Application for Waiver of Court Fees and submit it with your initial filing. The court will review your financial circumstances and grant the waiver if you qualify.
Joint Simplified Dissolution Alternative
Couples divorcing a common law marriage may qualify for Illinois's streamlined Joint Simplified Dissolution process if they meet strict requirements: no minor children, total marital property under $50,000 after debts, combined annual income under $60,000 with neither spouse earning over $30,000, married less than 8 years, no retirement benefits except IRAs totaling under $10,000 combined, neither spouse owns real estate, and both spouses waive maintenance. This expedited process can conclude in as little as 30 days and typically costs less than $500 total.
Proposed Legislative Changes: House Bill 4404
Illinois State Representative Daniel Didech introduced House Bill 4404, the "Uniform Cohabitants' Economic Remedies Act," which would transform property rights for unmarried couples. If enacted, this legislation would recognize contributions made by each party during cohabitation and provide fairer property division upon separation regardless of marital status. While this bill had not passed as of the 2026 legislative session, it signals potential future changes to Illinois law affecting unmarried couples.
Frequently Asked Questions
Can I get a common law divorce in Illinois if we never formally married?
No, Illinois cannot dissolve a relationship that was never a legal marriage. Illinois abolished common law marriage in 1905, so couples who only lived together in Illinois are not legally married regardless of relationship duration. Without a valid marriage, there is no divorce to file. However, you may have contract or equitable claims for property division under the Blumenthal v. Brewer framework if you had agreements about shared property.
How do I prove my common law marriage from another state is valid in Illinois?
You must demonstrate that the originating state recognizes common law marriage and that you satisfied all requirements in that state. Evidence typically includes joint tax returns filed as married, shared bank accounts, property deeds listing both parties as married, testimony from friends and family, documents such as Texas's Declaration of Informal Marriage, and any correspondence or records showing you held yourselves out as married in the originating state.
What filing fee should I expect for divorcing a common law marriage in Illinois?
Filing fees range from $210 to $388 depending on the county. Cook County charges $388 for the petitioner and $251 for the respondent's appearance. DuPage County charges $348, while most other Illinois counties fall between $210 and $350. These fees are current as of March 2026; verify with your local circuit clerk before filing.
How long do I need to live in Illinois before filing for divorce from a common law marriage?
Under 750 ILCS 5/401, at least one spouse must have been an Illinois resident for 90 days before the court can enter a final dissolution judgment. You can file your petition before completing the 90 days, but the divorce cannot be finalized until the residency requirement is met. Military personnel stationed in Illinois for 90 days also satisfy this requirement.
Will Illinois divide property equally in a common law marriage divorce?
Not necessarily. Illinois uses equitable distribution under 750 ILCS 5/503, meaning property is divided fairly but not always 50/50. Courts consider 12 factors including each spouse's contributions, marriage duration, economic circumstances, and tax implications. One spouse may receive 60% or more of marital assets if factors such as disparate earning capacity, health issues, or custodial responsibilities justify an unequal division.
What happens to property I brought into the common law marriage?
Property owned before the marriage is classified as non-marital property and generally remains with the original owner under 750 ILCS 5/503(a). However, if you commingled non-marital assets with marital property (such as depositing inherited funds into a joint account), the non-marital character may be lost. Maintaining separate accounts and clear records helps protect pre-marital assets.
Can I receive spousal support after divorcing a common law marriage in Illinois?
Yes, maintenance (spousal support) is available in common law marriage divorces using the same guidelines as other divorces. For combined gross incomes under $500,000, the formula is 33.33% of the payor's net income minus 25% of the payee's net income, capped at 40% of combined net income. Duration depends on marriage length, ranging from short-term for brief marriages to indefinite for marriages of 20+ years.
What if my partner and I disagree about whether we have a common law marriage?
The court will hold a hearing to determine whether a valid common law marriage exists. The party claiming marriage must prove all elements were satisfied in the originating state. If the court finds no valid marriage, it cannot proceed with divorce proceedings. The party would then be limited to contract or equitable claims for property, which have different standards and remedies than divorce.
Should I create a cohabitation agreement if I'm living with my partner in Illinois?
Yes, a cohabitation agreement is strongly advisable for unmarried couples in Illinois. Without a valid marriage, you have no automatic property rights, no claim to support, and no inheritance rights unless specified in a will. A properly drafted cohabitation agreement establishes clear expectations, protects both parties' interests, and provides legal recourse if the relationship ends. The cost typically ranges from $500 to $2,500 for attorney-drafted agreements.
How does Illinois handle children from a common law marriage in divorce?
Children born to common law married couples have identical rights to children of ceremonially married parents. Illinois courts allocate parental responsibilities (decision-making authority) and parenting time based on the children's best interests under 750 ILCS 5/602.5. Child support follows the Income Shares Model, calculating support based on both parents' combined net income. The common law marriage status has no effect on children's rights or support calculations.