Illinois does not recognize palimony as a legal right, and the word itself carries no meaning in the state’s code. A former unmarried partner can sometimes recover money or property, but only through a standard contract or equitable claim that stands on its own economic footing, separate from the fact that the couple lived together. Claims that depend on the relationship itself are barred.
Why Illinois Blocks Support Claims Between Unmarried Partners
Illinois has refused to recognize common-law marriage since 1905. Under 750 ILCS 5/214, any common-law marriage formed in the state after June 30, 1905, is legally invalid.1Illinois General Assembly. 750 ILCS 5/214 – Invalidity of Common Law Marriages Length of the relationship does not matter. Thirty years of shared bills, a shared home, and shared children still leave two people as legal strangers when the relationship ends.
Because the Illinois Marriage and Dissolution of Marriage Act governs spousal maintenance and property division only for married couples, none of it applies to unmarried partners. There is no statutory right to ongoing support, no automatic claim to the other person’s income, and no default division of assets acquired during the relationship.
The Illinois Supreme Court reinforced this in 1979 in Hewitt v. Hewitt, holding that granting property rights to unmarried cohabitants would contravene the public policy behind the state’s marriage statute.2Justia. Hewitt v. Hewitt For decades, that ruling shut down almost every effort by a former partner to claim a share of the other’s assets.
What Blumenthal v. Brewer Actually Changed
The 2016 decision in Blumenthal v. Brewer is often described as opening a door for unmarried partners. It did not open much of one. The Illinois Supreme Court affirmed that claims rooted in a marriage-like relationship are still barred under Hewitt and reinstated the trial court’s dismissal of the property claims in that case.3Justia. Blumenthal v. Brewer
What the court did do was define the edge of the bar. Hewitt, it explained, “only disallows unmarried cohabitants who live in a marriage-like relationship from accessing, under the guise of an implied contract, the rights and protections specified in the Marriage and Dissolution Act.” Cohabitants remain free to form “valid contracts about independent matters, for which sexual relations do not form part of the consideration and do not closely resemble those arising from conventional marriages.”3Justia. Blumenthal v. Brewer
So a claim survives only if it would exist between any two people regardless of romance. If it depends on the couple having lived together as partners, it fails. Most claims fail for exactly that reason.
Written Cohabitation Agreements
The most reliable protection is a written agreement between the partners. A cohabitation contract is enforceable the same way any other contract between adults is enforceable, because it exists independently of the romantic relationship.
The consideration, meaning what each person gives and receives, must have nothing to do with the sexual or domestic side of the relationship. Business services, contributions to a specific asset, management of a joint venture, and profit-sharing from a commercial enterprise all qualify. A promise of financial support in exchange for companionship or homemaking likely does not, because those contributions are too tied to the relationship itself.3Justia. Blumenthal v. Brewer
A workable agreement includes a clear description of the independent economic exchange, specific dollar amounts or formulas for any payments or property division, signatures from both parties, and full identification of any real property involved. Notarization is not required but strengthens enforceability. If real estate is part of the deal, the writing requirement is not optional: the Illinois Statute of Frauds makes an oral promise to share ownership of a house unenforceable.
Oral agreements about independent financial matters are not automatically invalid, but proving them years later against a partner who now disputes every word is a losing posture. Written terms carry the case; memory does not.
Claims Without a Written Agreement
When no contract exists, two equitable theories still leave room to recover, provided the claim rests on economic contributions rather than the relationship.
Unjust Enrichment
An unjust enrichment claim in Illinois requires three showings: you conferred a benefit on your former partner, your partner accepted and retained it, and it would be unfair to keep that benefit without compensating you. What matters is specific, traceable money moving in a specific direction. Bank records showing you paid your partner’s mortgage, receipts for renovations to property titled only in their name, or documented funds you put into their business are the kind of evidence that carries a claim.
Vague accounts of “building a life together” and commingled household spending are exactly what Hewitt and Blumenthal reject. In Blumenthal, the court rejected a claim based on commingled funds because the arrangement was “intimately related and dependent on” the marriage-like relationship. In the same opinion, the court pointed to Spafford v. Coats as an example of claims with “an economic basis independent of the nonmarital, cohabiting relationship,” where recovery was permitted.3Justia. Blumenthal v. Brewer Most cohabitation cases turn on which side of that line the facts fall.
Constructive Trust
A constructive trust is a court-imposed remedy that transfers ownership of specific property to the person who should rightfully hold it. Illinois courts impose one in limited circumstances, typically involving a breach of fiduciary duty or actual fraud, and the property must be identifiable and traceable to the wrongful conduct.
In a cohabitation setting, this can apply where one partner titled property solely in their own name despite an explicit understanding that both partners owned it, or diverted jointly earned business income into a personal account. The court is not being asked to divide marital-style property. It is being asked to correct a specific wrong involving a specific asset.
Deadline to Bring a Claim
Illinois imposes a five-year statute of limitations on oral contract claims, unjust enrichment claims, and most other civil actions not covered by a more specific deadline.4Illinois General Assembly. 735 ILCS 5/13-205 Written contract claims generally get ten years. The clock typically runs from the end of the relationship or the alleged breach, not from when the couple first moved in together.
Five years feels long, but people miss it. Financial claims are rarely the priority in the months after a breakup, and by the time someone is ready to pursue them, the window can already be closing.
Where the Case Gets Filed
Because there is no family-law remedy for unmarried partners, these cases are filed as ordinary civil lawsuits in the Illinois Circuit Court, in the county where the couple lived or where the relevant property sits.
The complaint has to plead a specific theory: breach of an express contract, unjust enrichment, constructive trust, or a combination. It also has to plead facts specific enough to show the claim is economically independent of the romance, because the other side will move to dismiss under Hewitt. After service, the defendant generally has 30 days to answer or move to dismiss. Filing fees vary by county and by claim amount, and additional costs typically follow for service, discovery, and any needed valuations or appraisals.
If a cohabitation agreement contains an arbitration or mediation clause, a court will generally enforce it. Even without one, mediation is often worth considering, because these cases involve tangled financial histories that a trial court has limited time to sort through.
Tax and Benefit Gaps to Know About
Unmarried partners lose several protections that divorcing spouses take for granted, and the losses are easy to miss until a bill or a benefits denial arrives.
Federal law makes property transfers between spouses or former spouses that are incident to a divorce tax-free. Section 1041 of the Internal Revenue Code limits that benefit to a “spouse” or “former spouse” where the transfer relates to the end of the marriage.5Office of the Law Revision Counsel. 26 USC 1041 – Transfers of Property Between Spouses or Incident to Divorce Unmarried partners do not qualify. Transferring appreciated property to a former partner as part of a settlement can trigger capital gains tax on the built-in appreciation.
The IRS treats unmarried partners as unrelated individuals for all federal tax purposes, including those in registered domestic partnerships or civil unions that are not marriages under state law.6Internal Revenue Service. Answers to Frequently Asked Questions for Registered Domestic Partners and Individuals in Civil Unions Periodic payments between former partners may be treated as taxable income or as a taxable gift depending on the circumstances. For 2026, the annual gift tax exclusion is $19,000 per recipient.7Internal Revenue Service. Gifts and Inheritances A lump-sum transfer or annual support amount above that can require a gift tax filing, though actual tax generally applies only after the lifetime exclusion of $15,000,000 is exhausted.8Internal Revenue Service. Whats New – Estate and Gift Tax IRS guidance on unmarried property divisions is thin, and tax professionals disagree on treatment. Get tax advice before signing any settlement involving significant assets.
Social Security is another shutout. Qualifying as a surviving spouse generally requires at least nine months of marriage before the partner’s death.9Social Security Administration. Who Can Get Survivor Benefits Cohabitation does not substitute, no matter how long it lasted. Spousal retirement benefits carry the same marriage requirement. A married partner in a lopsided-earnings relationship can claim up to half of the higher earner’s benefit or survivor benefits after their death. An unmarried partner gets nothing on that record.
What to Do Before Anything Goes Wrong
The cheapest protection is a written cohabitation agreement drafted while both partners are on good terms. It should identify who owns what, how shared expenses are handled, and what happens to jointly purchased property if the relationship ends. Every financial term should tie back to an economic contribution rather than to the relationship itself.
Title matters. If both partners contribute to a home, both names belong on the deed. If one partner funds improvements to property the other owns, document the arrangement and keep receipts. Keep separate accounts for individual assets even if a joint account handles household bills. The clearer the paper trail, the easier it is to prove an independent economic claim if the relationship ends.
Illinois gives unmarried partners almost no default protection. Whatever protection exists has to be built in advance or proven afterward, and building it in advance costs a fraction of proving it later.