Prenuptial Agreements in the Tri-County Area: Enforceability and Drafting Tips for 2026

A prenuptial agreement is one of the most misunderstood legal tools in Michigan family law — and one of the most powerful. It is not a sign of distrust. It is a strategy.

For couples in Macomb County, Oakland County, and Wayne County, a well-drafted prenup can prevent years of litigation, protect family businesses and inherited wealth, and provide clarity during one of life’s most emotional transitions.

Here’s the reality most couples discover too late: Michigan is an equitable distribution state. That means a judge — not you — decides what’s “fair” if your marriage ends without an agreement in place. And “equitable” does not mean equal. Under MCL 552.19, courts divide property based on a long list of factors, and the outcome is rarely what either party expects.

A prenuptial agreement gives you and your partner control over those decisions while you’re still communicating well and planning together. But enforceability is everything. A prenup that doesn’t meet Michigan’s legal requirements — or that a court considers unconscionable — is worth less than the paper it’s printed on.

This guide breaks down what Michigan law requires, what Tri-County Area couples should include, and how to avoid the drafting mistakes that lead to invalidation.

Michigan’s Legal Framework for Prenuptial Agreements

Prenuptial agreements are enforceable in Michigan through a combination of statute and case law. There is no single “prenuptial agreement act” — instead, Michigan courts look to several legal sources when evaluating whether a prenup is valid and binding.

The statutory foundation begins with MCL 557.28, which provides that “a contract relating to property made between persons in contemplation of marriage shall remain in full force after marriage takes place.” This means Michigan has long recognized the right of couples to make binding financial agreements before they marry.

Michigan’s Statute of Frauds adds a critical requirement. Under MCL 566.132(1)(c), an agreement “made upon consideration of marriage, except mutual promises to marry” is void unless it is in writing and signed by the party to be charged. In plain terms: Michigan does not recognize oral prenuptial agreements. If it isn’t written and signed, it doesn’t exist.

The landmark case that removes any remaining doubt about enforceability is Rinvelt v Rinvelt, 190 Mich App 372 (1991). Before Rinvelt, no Michigan case had specifically held that prenuptial agreements are enforceable in the context of a divorce case. The Michigan Court of Appeals settled that question definitively — prenuptial agreements are enforceable in Michigan divorces, provided they meet fundamental standards of fairness and voluntariness.

“Many Michigan residents don’t realize that the enforceability of prenups in divorce isn’t just a matter of statute — it was established through decades of case law development. Understanding how Michigan courts actually evaluate these agreements is critical to drafting one that holds up.”

Protecting Premarital Assets in a Tri-County Area Prenup

Under Michigan law, premarital assets can become marital property through a process called commingling. This is one of the most common and costly mistakes couples make.

Here’s a concrete example that plays out regularly in Southeast Michigan: You own a home in Oakland County before the marriage. After the wedding, you and your spouse refinance the mortgage jointly, use marital income to fund a $75,000 kitchen renovation, and retitle the property in both names. What was once clearly your separate asset is now a classification fight — and an expensive one. The same principle applies to business interests, retirement accounts, and investment portfolios.

A well-drafted prenup addresses these risks by clearly identifying and protecting:

Premarital real estate — particularly relevant in Oakland County and Macomb County, where property values have fluctuated significantly over the past decade
Family businesses and professional practices — business valuation disputes are among the most contentious and expensive components of Michigan divorces
Inheritance and trust distributions — even expected future inheritances can be addressed proactively
Retirement accounts and investment portfolios — including 401(k) balances, IRAs, and brokerage accounts accumulated before the marriage
Premarital debt — protecting one spouse from the other’s student loans, credit card balances, or business liabilities

The key is specificity. Vague language like “each party keeps their own property” invites litigation. Effective prenups include asset schedules with current valuations and explicit rules for how appreciation, income, and contributions will be treated during the marriage.

Essential Clauses Every Michigan Prenup Should Include

Because MCL 557.28 broadly recognizes property contracts made in contemplation of marriage, Michigan prenups can address a wide range of financial matters. Courts will generally uphold provisions related to property rights, debt allocation, and spousal support — so long as the agreement is fair, voluntary, and made with full knowledge of each party’s financial circumstances.

The one major exception: you cannot predetermine child support or child custody in a prenup. Those decisions are always governed by the child’s best interests at the time of any proceeding.

Every enforceable Tri-County Area prenup should include these critical provisions:

Property classification and division terms. Specify which assets remain separate, which become marital, and how commingled assets will be treated. Include detailed asset and debt schedules as exhibits.

Spousal support provisions. Michigan allows couples to waive, limit, or define spousal support obligations in a prenup. However, note that for any divorce finalized after December 31, 2018, alimony is no longer tax-deductible for the payer or taxable income for the recipient — a significant change that affects how support provisions should be structured. If waiving support, include a safety valve — for example, a provision that the waiver applies unless enforcement would leave a spouse unable to meet reasonable needs due to disability or a long-term absence from the workforce. Alternatively, use a step-down, cap, or sunset approach to reduce unconscionability risk in long marriages.

Debt allocation. Define responsibility for premarital debts and establish rules for debts incurred during the marriage. This is especially critical when one spouse has significant student loan or business debt.

Business and professional practice protections. If either spouse owns a business, the prenup should address valuation methods, whether business appreciation is separate or marital, and how buy-sell provisions interact with divorce.

Sunset clauses. Some couples include provisions that modify or eliminate certain terms after a set number of years — for instance, adjusting spousal support waivers after 15 or 20 years of marriage. Courts generally uphold sunset clauses when they’re clearly drafted.

Financial disclosure exhibits. Attach complete financial disclosures as part of the agreement itself, creating a clear record that both parties entered the contract with full knowledge.

Advanced Drafting Clauses Sophisticated Clients Expect

Beyond the essentials, experienced Michigan family law attorneys include provisions that reduce future litigation and signal to courts that the agreement was drafted with care. These “pro drafting” touches are what separate a prenup that survives judicial scrutiny from one that invites a challenge:

Definitions clause. Clearly define “separate property,” “marital property,” “commingling,” “income,” and “appreciation.” Ambiguity in these core terms is where enforcement battles begin.
Tracing and reimbursement language. Establish how premarital asset appreciation will be tracked — especially for real estate renovations funded with marital dollars and business reinvestment. Include reimbursement mechanisms so contributions are accounted for even if the asset stays separate.
Attorney fee clause. Specify whether the prevailing party in an enforcement action or challenge recovers legal fees, or include fee-shifting for bad-faith challenges. This discourages frivolous attacks on the agreement.
Severability provision. State explicitly that if one clause is struck down, the remainder of the agreement survives. Without severability, a single defective provision can void the entire prenup.
Choice of law and venue. Designate Michigan law as governing and, where appropriate, specify Tri-County Area venue for any enforcement proceedings. This prevents forum-shopping if one party later relocates.

Common Enforcement Challenges in Michigan Courts

In our experience serving families throughout Macomb County, Oakland County, and Wayne County, the most common reason prenups fail isn’t bad drafting — it’s bad process. Couples focus on what the agreement says without paying enough attention to how it was created, presented, and signed.

Michigan courts, following the framework established in Rinvelt v Rinvelt and subsequent case law, evaluate prenuptial agreements based on several key factors. A court may refuse to enforce a prenup if:

The agreement was involuntary — one party was pressured, coerced, or given insufficient time to review and understand the terms
There was inadequate financial disclosure — one party concealed assets, debts, or income, preventing the other from making an informed decision
The agreement is unconscionable — meaning it is so one-sided that enforcement would shock the conscience of the court

Wayne County courts have been particularly attentive to power dynamics between parties. When one spouse has significantly more wealth, legal sophistication, or access to attorneys, courts scrutinize whether the less-advantaged party truly understood what they were signing.

Other common enforcement challenges include:

No independent counsel. While Michigan does not legally require both parties to have separate attorneys, courts view the absence of independent representation as a red flag for voluntariness. This is one of the strongest indicators judges consider.

Last-minute execution. Agreements signed within days of the wedding ceremony face elevated challenge risk. Courts evaluate whether both parties had meaningful time to review, negotiate, and consult an attorney before signing.

Incomplete or outdated financial disclosures. If asset values listed in the agreement were materially inaccurate or outdated at the time of signing, the entire agreement may be vulnerable.

Unconscionable spousal support waivers. A waiver that leaves one spouse destitute — particularly after a long marriage with children — may not survive judicial review, regardless of what was agreed to years earlier.

What Michigan Courts Actually Scrutinize: An Enforceability Checklist

Bad process kills good drafting. Before signing, confirm your prenup meets the standards Michigan judges actually apply:

Signed well before the wedding — avoid last-week execution. Months ahead is ideal; 30–60 days is the minimum.
Independent counsel for both parties — not legally required, but it provides enormous credibility and is one of the strongest indicators of voluntariness.
Complete financial disclosures attached as exhibits — assets, debts, and income, with current valuations.
No “sign or the wedding is off” pressure — no surprise drafts, no ultimatums, no emotional coercion.
Terms that remain fair over time — provisions that don’t become oppressively one-sided after major life changes like children, disability, or career sacrifice.

This checklist reflects what Michigan courts focus on most. An agreement that checks all five boxes is dramatically more likely to survive a challenge.

Prenup vs. Postnup vs. Estate Plan: How They Work Together

A prenuptial agreement is one piece of a broader financial protection strategy — not the whole picture. Understanding how a prenup interacts with postnuptial agreements and estate plans prevents gaps that create costly problems.

A prenup controls what happens in divorce — property classification, asset division, and spousal support. An estate plan controls what happens at death — inheritance, asset distribution, and who makes medical or financial decisions if you’re incapacitated. These two documents serve different legal purposes, and having one does not replace the other.

Here’s a critical detail many couples overlook: beneficiary designations on retirement accounts, life insurance, and transfer-on-death accounts can override both wills and prenups. If your prenup says your spouse waives rights to your 401(k), but your beneficiary designation still names your spouse, the beneficiary designation typically wins. Coordinating these documents is essential.

A postnuptial agreement addresses changes that arise after the wedding — new businesses, inheritance, career shifts, or shifts in the financial landscape. Think of a postnup as an update mechanism for your prenup, governed by the same core requirements of fairness, voluntariness, and full disclosure.

When all three are aligned, couples in Macomb County, Oakland County, and Wayne County have comprehensive protection for both life transitions and worst-case scenarios.

Updating Your Prenup: When and Why It Matters

Life changes. Your prenuptial agreement should change with it. Michigan law permits couples to amend or revoke prenuptial agreements after marriage through a postnuptial agreement — but the same core principles apply. Any modification must be in writing, signed by both parties, and meet standards of fairness and voluntariness to be enforceable.

An important reality to understand: Postnuptial agreements are generally enforceable in Michigan, but they are often scrutinized more heavily than prenups because they are signed after marriage — when leverage dynamics, financial dependence, and power imbalances can shift. Process, disclosure, and independent counsel matter even more in the postnup context.

Consider updating your prenup through a postnuptial agreement when:

One spouse starts or acquires a business
You purchase significant real estate together
Children are born — while custody and support terms can’t be predetermined, the financial landscape shifts dramatically
One spouse leaves the workforce to care for children or aging parents
Either party receives a substantial inheritance or gift
There is a major change in income or net worth
You relocate across Michigan or out of state

“Many couples in the Tri-County Area draft their original prenup when both partners are early in their careers. A decade later, the financial picture looks entirely different. An agreement that made sense when both spouses earned $60,000 may be grossly unfair when one earns $300,000 and the other stepped away from their career to raise children.”

Verbal modifications to a prenuptial agreement have no legal effect in Michigan. Under MCL 566.132(1)(c), any agreement made upon consideration of marriage must be in writing and signed to be enforceable. The same principle extends to modifications — if it isn’t documented, it isn’t binding.

Frequently Asked Questions About Prenuptial Agreements in Michigan

Can a prenup be invalidated in Michigan?

Yes, a prenup can be invalidated if it was signed involuntarily, lacked adequate financial disclosure, or is unconscionable. Under the standards established in Rinvelt v Rinvelt and subsequent Michigan case law, the party challenging the agreement bears the burden of proving one of these grounds. Courts also consider whether both parties had independent legal counsel and adequate time to review the agreement before signing. Agreements signed under duress — including emotional pressure near the wedding date — are particularly vulnerable.

How much does a prenuptial agreement cost in Michigan?

A prenuptial agreement in Michigan typically costs between $1,500 and $5,000, depending on complexity. Straightforward agreements addressing basic asset protection tend to cost less, while prenups involving business valuations, trust structures, or high-net-worth estates require more drafting time and review. Each party should have their own attorney, which means the total cost accounts for both sides. Compared to the $15,000–$50,000+ cost of contested property division litigation in divorce, a prenup is a fraction of the investment.

Can a prenup waive spousal support in Michigan?

Michigan courts often enforce spousal support provisions in prenuptial agreements, but may decline enforcement if the waiver would be unconscionable at the time of divorce. This is especially true in long marriages where one spouse sacrificed career advancement for the family. If the waiver would leave one party unable to support themselves while the other maintains a comfortable lifestyle, a court may set it aside — regardless of what was signed years earlier. Including a safety valve, step-down provision, or sunset clause significantly improves the chances a support waiver survives judicial review.

Does Michigan require both parties to have separate lawyers for a prenup?

No, Michigan does not legally require both parties to have independent attorneys. However, having separate counsel is one of the strongest indicators of voluntariness and fairness. Courts in Oakland, Macomb, and Wayne Counties are far more likely to uphold agreements where both parties were independently represented. Sharing an attorney — or having one party go unrepresented — creates a significant enforceability risk.

When should we sign a prenup before the wedding?

Ideally, you should finalize and sign your prenuptial agreement at least 30 to 60 days before the wedding — but earlier is better. Months, not weeks. While Michigan law does not mandate a specific waiting period, courts evaluate whether both parties had adequate time to review, negotiate, and seek counsel. Agreements signed in the final week before a wedding face a substantially higher risk of being challenged as involuntary. Starting the process three to six months before the wedding gives both parties time to negotiate meaningfully and consult independent attorneys without the pressure of an approaching ceremony.

Can a prenup address what happens to our house?

Yes, a prenuptial agreement can specify what happens to the marital home in the event of divorce. This includes buyout terms, sale procedures, timeline requirements, and how mortgage obligations will be handled. For couples purchasing a home together in Macomb County, Oakland County, or Wayne County — where home values can vary significantly by community — a clear prenup provision prevents one of the most contentious disputes in Michigan divorces.

How does a prenup interact with my estate plan?

A prenuptial agreement and an estate plan serve different legal purposes and must be coordinated. Your prenup governs what happens in divorce; your estate plan governs what happens at death or incapacity. Critically, beneficiary designations on retirement accounts, life insurance policies, and transfer-on-death accounts can override both your will and your prenup. If your documents aren’t aligned, the protections you negotiated in your prenup may not function as intended. Couples should review both their prenup and estate plan with their attorneys whenever there’s a major life change.

Protect Your Future Before You Walk Down the Aisle

A prenuptial agreement is an act of partnership, not a prediction of failure. It gives both spouses certainty, prevents costly courtroom battles, and preserves the ability to make financial decisions together — rather than leaving them to a judge who doesn’t know your family.

At Boroja, Bernier & Associates, we help couples throughout Macomb County, Oakland County, Wayne County, and Southeast Michigan draft prenuptial agreements that are thorough, enforceable, and designed to hold up under judicial scrutiny. Our family law attorneys understand what Michigan courts expect and what causes agreements to fail — because we’ve seen both outcomes firsthand.

To schedule a consultation with the Michigan family law attorneys at Boroja, Bernier & Associates, call our law offices at (586) 991-7611. With our main office in Shelby Township and satellite offices in Troy, Ann Arbor, and Lansing, we’re here to help you start your marriage with confidence and clarity.