Lawrence Ryan Investigations

Lawrence Ryan Investigations Chicago Illinois

How to Prove Cohabitation in Illinois

Young couple cohabitating

According to a study by the Pew Research Center, the percentage of cohabitation has increased. Throughout the years, it has become more and more common for couples to cohabitate before getting married or even having wedding plans at all. The study showed that 59% of young adults have lived with their partner without marrying them.

What is Cohabitation?

Cohabitation is the case of a couple living together without being married. The concept may vary between states.

Some states don´t include same-gender couples who live together under the cohabitating concept.  States like Illinois, don´t entirely accept cohabitation. In case the couple cohabitating splits, the rules of property division will not apply to them since they are not married.

Youg adults cohabitating

Having a valid cohabitation agreement may help the case and simplify all legal matters if the couple splits.

Cohabitation comes with legal and financial issues that are important to be considered. A family law attorney can help you with this document to arrange how finances will be handled, such as utility bills, rent, and debt responsibility. Having this agreement will also include parental roles in case there are children involved. Added to that, if you have responsibilities with a previous relationship, there could be legal consequences.

What happens if you are divorced or in the process of divorcing, and you start cohabitating with your new partner?

What happens to your child custody and how it affects your child support case?

For example, if you are divorced, and receiving spousal support, but start living with your new partner, the ex-spouse can file a motion to terminate alimony.  In some states, cohabitating is reason enough for your ex-spouse to stop paying alimony. In others, the judge needs evidence that cohabitating has helped you financially, and you no longer need your ex-spouse to maintain you. No matter the state, the spouse has the burden of proving cohabitation.

Cohabitation Agreement

How does cohabitation affect child support?

When it comes to the matter of the petition of changing the spousal maintenance or child support order, the same rules apply to both.

The truth is that child support orders cannot be modified just by proving that one of the spouses is living with a new partner. The spouse cohabitating must have experienced a substantial financial change to have the order modified.

Due to the way child support is calculated, sometimes it is hard to prove that because of cohabitation, there has been a substantial change. If you are interested in calculating child support payments, please visit

The non-parent spouse or partner is not legally obliged to contribute with the child support. Though, it may be considered in the case since it affects the economic prospects of the parent involved.

Child support will always be a legal responsibility for both parents. The only way cohabitation may affect child support is by increasing or decreasing the amount of support given.

When it comes to child custody, each case is different, and it depends on many factors the judge will need to take into consideration.

House going through a divorce

How to prove cohabitation?

Proving cohabitation is not just helpful for child support cases, but also other cases such as alimony obligations, and even to terminate alimony.

It is essential to know what factors define the cohabitation concept.

Factors that the judge may use in court to define the relationship status as a cohabitation:

  • Length of the relationship
  • Amount of time the couple shares
  • Type of activities they attend together
  • The interrelation of their personal affairs
  • If they spend vacations together
  • If they spend the holidays together

It is hard to list all facts that can help cases with the evidence of cohabitation due to the uniqueness of each case.

Some of the evidence that has been used in previous cases are:

  • Photographic (photo or video) evidence with the parties involved entering the place of residence and staying overnight.
  • Documentation, such as magazine subscriptions, credit card statements, and other legal documents that show the couple has the same address.
  • Legal papers, or any type of document that shows the couple shares a title or leases property jointly.
  • Information gathered from social media accounts showing they are a couple.
  • Any type of evidence that the couple shares bank accounts
  • Photographs of the couple spending holidays together or on vacation.
  • Evidence that neither of the parties involved has other residences.

Evidence to prove cohabitation


A private investigator can provide this proof to be used in court and help you win your case. Hiring a private investigator that helps you legally get that proof you need to your case is the top solution. A private investigator can implement their professional training and all of their tools to gather the case information needed legitimately, without harming the case. They collect information by doing surveillance, checking public records, examining items from the garbage, and reviewing their social media accounts.