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Category: Divorce

Before or After You Say ‘I Do’: A Guide to Prenuptial and Postnuptial Agreements

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Written by Olivia St. Clair Long on 7.1.25

When it comes to love and marriage, no one likes to think about what might go wrong. But being prepared doesn’t mean you expect the worst. It means you’re protecting your future and building your relationship on a foundation of transparency and trust.

Prenuptial and postnuptial agreements are legal tools designed to do just that. Before we dive into the details, let’s start with the biggest difference between the two.

  • Prenuptial Agreements (Prenups) are signed before you get married.
  • Postnuptial Agreements (Postnups) are signed after you’re already married.

Timing is just the beginning. In this blog, we will break down how these agreements work, when they make sense, and what to watch for under Illinois law.

What is a Prenuptial Agreement?

A Prenuptial Agreement, often called a prenup, is a legal contract signed by both parties before marriage. Its primary purpose is to outline how finances, property, and spousal support will be handled if the marriage ends by divorce, separation, or death.

Common provisions in a prenup include:

  • Division of premarital and marital assets
  • Responsibility for debts incurred before and during the marriage
  • Terms for spousal maintenance (alimony)
  • Protection of family businesses or inheritances
  • Clarification of financial responsibilities during the marriage

In Illinois, for a prenup to be enforceable:

  • It must be entered into voluntarily
  • Both parties must fully disclose their finances
  • The terms must be fair and not unconscionable at the time of enforcement
  • The agreement must be in writing and signed by both parties

Pros and Cons of Prenuptial Agreements

Pros:

  • Promotes transparency and communication before marriage
  • Protects premarital assets and family interests
  • Sets clear expectations for financial responsibilities
  • Can help avoid lengthy legal disputes during divorce
  • Customizable to fit your unique relationship

Cons:

  • Can feel unromantic or trigger emotional discomfort
  • May not anticipate future changes, such as children or health concerns
  • Can be challenged if deemed unfair or coerced

What is a Postnuptial Agreement?

A Postnuptial Agreement (postnup) is similar to a prenup, but it’s signed after the wedding. It allows spouses to redefine the financial responsibilities or protections based on new circumstances.

Common reasons couples pursue a postnup:

  • A significant shift in income or career, such as one spouse leaving a job to raise children
  • Receiving a large inheritance or financial gift
  • Starting or expanding a business
  • Marital conflict followed by reconciliation
  • Simply missing the opportunity to sign a prenup before marriage

In Illinois, postnups face greater legal scrutiny with courts closely examining:

  • Whether both parties entered the agreement willingly and with full understanding
  • Whether there was complete financial disclosure
  • Whether the terms are fair and equitable at the time of enforcement

Pros and Cons of Postnuptial Agreements

Pros:

  • Useful if a prenup wasn’t created
  • Reflects current financial realities and life changes
  • Can protect one spouse during transitions such as leaving a career
  • It may strengthen a marriage through renewed communication

Cons:

  • Courts scrutinize postnups more rigorously
  • It must be carefully drafted to avoid claims of coercion or unfairness
  • Timing can raise concerns about voluntariness

When to Consider a Prenup

A prenup is especially helpful when either party has:

  • Significant premarital assets such as real estate, investments, or retirement accounts
  • Business ownership or professional practices
  • Large debts such as student loans or credit card balances
  • Children from prior relationships who need financial protection
  • Family wealth or inheritance concerns
  • A desire to clarify spousal maintenance expectations

Far from being a sign of mistrust, prenups promote open, honest conversations and provide clarity before entering marriage.

When a Postnup Makes Sense

Even after marriage, it’s never too late to create financial clarity. A postnup can be a powerful tool if:

  • You or your spouse received a large inheritance or gift
  • One spouse has left the workforce to raise children
  • You’ve started a new business or made high-risk investments
  • You’re reconciling after a period of separation or conflict
  • You missed the opportunity to sign a prenup but want legal protections

Postnups offer a second chance to establish peace of mind for the future.

Can You Have Both a Prenup and a Postnup in Illinois?

Yes, in Illinois, it’s possible and sometimes advisable to have both a prenuptial and a postnuptial agreement. A prenuptial agreement sets the financial and legal expectations before marriage. However, as life circumstances change, such as career changes, the birth of children, or significant financial shifts, may require adjustments to those original terms in the prenup. A postnuptial agreement allows couples to update or supplement their original agreement to reflect their current situation.

Under Illinois law, both prenuptial and postnuptial agreements are enforceable if they meet specific legal criteria:

  • Both parties must agree willingly and without coercion.
  • Each party must fully disclose their assets and liabilities.
  • The agreement must be fair and not unconscionable at the time of enforcement.
  • The agreement must be in writing and signed by both parties.

It is important to note that while postnuptial agreements are recognized in Illinois, they are subject to greater legal scrutiny compared to prenuptial agreements. Any postnuptial agreement should be drafted carefully to ensure it meets all legal requirements and is enforceable.

Having both agreements can offer a comprehensive framework that adapts to changes over time, providing ongoing clarity and protection for both spouses.

Choosing the Right Agreement: How Prenups and Postnups Compare

While both agreements serve to protect your interests, they differ in timing, legal context, and court scrutiny.

Aspect Prenuptial Agreement Postnuptial Agreement
Timing Signed before marriage Signed after marriage
Legal Context Pre-marriage planning Adjusts rights within an existing marriage
Court Scrutiny Lower Higher due to potential undue influence
Use Case Planning and preparation Responding to life changes or missed prenup opportunity

No matter if you choose prenuptial or postnuptial agreements, we at O. Long Law, LLC, guide clients through these sensitive conversations with respect and clarity. Prenuptial and postnuptial agreements are not about expecting the worst. They are about building your marriage on a foundation of clarity, respect, and protection for both parties.

If you’re considering a prenup or postnup, contact O. Long Law, LLC today to schedule a consultation and build a strong, secure future together.