Why a Postnuptial Agreement — And When They Are Valid in Colorado
By Matthew C. Clawson, Colorado Family Law Attorney
Serving Colorado Springs, Falcon, Pueblo, Castle Rock, Parker, and the Entire Front Range
A postnuptial agreement—legally called a “marital agreement” in Colorado—is a powerful tool that allows married couples to define their financial rights and responsibilities by contract. Unlike a prenuptial agreement signed before the marriage, a postnuptial agreement is signed after the couple is already married and becomes legally enforceable immediately.
Postnups are increasingly used for asset protection, estate planning, marital stability, business interests, and financial clarity. However, Colorado has strict statutory requirements governing when postnuptial agreements are valid under the Colorado Uniform Premarital and Marital Agreements Act (UPMAA), C.R.S. §§ 14-2-301 to 14-2-310.
This article explains why couples use postnuptial agreements, exactly when they are enforceable, and the Colorado statutes that govern them.
What Is a Postnuptial Agreement in Colorado?
Under C.R.S. § 14-2-302(2), a postnuptial agreement (marital agreement) is defined as:
“An agreement between spouses who intend to remain married which affirms, modifies, or waives a marital right or obligation during the marriage or at legal separation, marital dissolution, death of one of the spouses, or the occurrence or nonoccurrence of any other event.”
Two key statutory elements:
- The spouses must already be married.
- They must intend to remain married at the time of signing.
This means:
- A postnup cannot be signed after a spouse has filed for divorce or legal separation.
- A postnup is not a separation agreement. (“Separation agreements” are governed by C.R.S. § 14-10-112, not the UPMAA.)
When does a postnup take effect?
Immediately.
Under C.R.S. § 14-2-307, a marital agreement:
“is effective on signing by both parties.”
Why Couples Sign Postnuptial Agreements
Colorado couples use postnuptial agreements for many reasons—some practical, some financial, some relational.
Below are the most common purposes, supported by statutory language.
1. To Provide Financial Clarity and Reduce Conflict
Money is a leading cause of marital stress. Postnups create structure and clarify:
- Ownership of property
- Management of finances
- Spending expectations
- What will happen if the marriage ends
- Financial boundaries
A postnup can define rights to property under C.R.S. § 14-2-302(4)(b) and (d).
2. To Protect Inherited or Separate Property
Many spouses sign postnups when:
- One spouse receives a significant inheritance
- A family trust is involved
- A family business wants asset protection
- Real estate is acquired or gifted
Colorado marital property law presumes that an increase in the value of separate property becomes marital unless proven otherwise.
A postnup allows the parties to “characterize, manage, or own” property per C.R.S. § 14-2-302(4)(b), preventing future disputes.
3. To Protect a Business or Professional Practice
Physicians, dentists, attorneys, military members, and business owners frequently use postnups to:
- Protect business ownership interests
- Define future appreciation as separate property
- Allocate debts, liability, or business revenue
- Prevent disruption of business operations in a divorce
Again, covered under C.R.S. § 14-2-302(4)(b) & (d).
4. To Rebuild Trust After Infidelity or Financial Misconduct
Couples sometimes enter a postnup as part of reconciliation after:
- Infidelity
- Hidden spending
- Financial mismanagement
- Addiction-related issues
- Broken trust
Although “infidelity clauses” are likely unenforceable (explained later), a postnup can still shift financial responsibilities and protect vulnerable spouses.
5. To Provide Predictability and Reduce Future Litigation
A postnup reduces uncertainty, legal fees, and risk by determining financial expectations in advance.
It becomes a kind of “marital insurance policy.”
Under C.R.S. § 14-2-306, no additional “consideration” is required—the intent to remain married is enough.
Postnuptial Agreements vs. Separation Agreements
This distinction is the single most important factor in enforceability.
Schedule a Confidential Consultation
Matthew C. Clawson, Colorado Family Law Attorney
Serving Colorado Springs, Falcon, Pueblo, Castle Rock, and Parker
For more information about
a divorce case review throughout Colorado, contact Matthew C. Clawson
We will answer your questions, evaluate your case, and advise you on the best course of action based on your individual needs and priorities.
We can be reached at www.clawsonattorney.com, and Matthew can be contacted directly at Matthew@clawson.law. For more information about our top-rated legal services, fill out our online form or call 719-634-1848 or 303-805-9353 to schedule a free initial consultation.
Legal Disclaimer- This article is for informational purposes only and does not constitute legal advice. Reading this content or contacting the attorney does not create an attorney-client relationship. Legal decisions and outcomes depend on the specific facts of each case. Colorado laws may change, and you should consult a licensed attorney for advice tailored to your circumstances. No guarantee is made regarding the accuracy or completeness of the information provided.