Are Prenups and Postnups Enforceable in PA?

Last updated October 4, 2026.

Generally yes. Under 23 Pa.C.S. 3106, a premarital agreement is enforceable unless the spouse challenging it proves, by clear and convincing evidence, that they did not sign voluntarily, or that before signing they did not receive fair and reasonable disclosure of the other's property and financial obligations, did not expressly waive further disclosure in writing, and did not otherwise have adequate knowledge of them. The burden is on the spouse who wants it set aside. Agreements made during or after the marriage can also exclude property from division (3501(a)(2)) and are enforced like court orders (3105(a)).

Two limits apply in every case: terms about child support and custody can always be modified by a court on changed circumstances (3105(b)), and only the parts of an agreement that meet the law's requirements will hold. For our divorce work in Media, see our family law page.

What does the 3106 test require?

Ground to set aside a premarital agreement	What the challenger must prove by clear and convincing evidence
Not voluntary	The challenger did not execute the agreement voluntarily (3106(a)(1))
No disclosure	All three: no fair and reasonable disclosure of the other's property or obligations; no voluntary, express written waiver of further disclosure; and no adequate knowledge of the other's property or obligations (3106(a)(2))

A "premarital agreement" is one made between prospective spouses in contemplation of marriage and effective on marriage (3106(b)). The section applies to premarital agreements signed on or after the effective date of the 2004 amendment that added it; older agreements were governed by the law that applied before then.

How is an agreement enforced or challenged, step by step?

Raise it in the divorce. The court in a divorce determines property rights "including any rights created by any antenuptial, postnuptial or separation agreement" (23 Pa.C.S. 3104(a)(1)).
List it on the inventory. Property claimed as non-marital because of an agreement is listed with the basis for the claim (Pa.R.C.P. 1920.33(a)(3)(ii)).
Challenge, if you will. The spouse who says the agreement is unenforceable raises the 3106 grounds and carries the burden of proof.
Hearing. In Delaware County, the county family court handbook says divorce matters go first to a hearing officer, with a de novo trial before a judge on request.
Enforcement. A party to an agreement may use any remedy in the Divorce Code to enforce it, as if it were a court order, whether or not it was merged into the decree, unless the agreement says otherwise (3105(a)).
Decree. The decree can include enforcement of agreements the spouses voluntarily entered (3323(b)).

Which terms can a court change later?

Section 3105 draws a clear line. A provision about child support, visitation or custody can be modified by the court on a showing of changed circumstances (3105(b)), because the court's duty runs to the child. A provision about existing property rights, alimony, alimony pendente lite, counsel fees or expenses is not subject to modification by the court, unless the agreement specifically says it may be (3105(c)).

That means couples should decide deliberately whether any alimony terms should be modifiable, and should expect child-related terms to be reviewed under the child's best interest if a dispute arises later. How alimony works without an agreement is explained in how long alimony lasts in Pennsylvania.

What can an agreement cover?

The Divorce Code recognizes agreements made before, during or after the marriage. Property excluded by a valid agreement is not marital property (3501(a)(2)), so a premarital or postnuptial agreement can keep a business, an inheritance or a pre-marriage home separate, along with its growth. A separation agreement at the end of a marriage typically settles the whole economic picture: property, debts, retirement accounts, alimony and counsel fees, and often custody and support terms that remain open to modification.

Without an agreement, the statute decides: marital property is presumed and divided under the equitable distribution factors; see what counts as marital property. The factors are in how property is divided.

How does a separation agreement end a divorce case?

A written settlement signed during the divorce is the most common agreement of all, and the rules give it a direct path to the decree. In a consent divorce, the decree can be entered once both consent affidavits are filed and the economic claims have been "resolved by agreement of the parties," along with the notice or waiver steps (Pa.R.C.P. 1920.42(a)(1)(iii)). If the court has already approved grounds and the spouses then settle the money issues, they file a praecipe asking for the decree, and any claim the agreement does not cover must be withdrawn first (1920.42(a)(4)). A spouse may withdraw an equitable distribution claim on the basis of the parties' written and filed agreement (Pa.R.C.P. 1920.17(b)(1)(i)).

Because the settlement then controls property, alimony and fees without later modification by the court unless it says otherwise (3105(c)), it deserves the same care as a premarital agreement: complete disclosure, time to review and clear terms about what happens on remarriage, cohabitation or death. The timeline from filing to decree is in how long a divorce takes in Pennsylvania.

What changes the answer?

Disclosure. Attaching complete financial disclosure, or a clear written waiver, removes the main ground for challenge (3106(a)(2)).
Voluntariness. Evidence that a spouse signed under pressure, such as on the eve of the wedding, bears on the voluntariness ground (3106(a)(1)).
When it was signed. Section 3106 applies to premarital agreements signed after the 2004 amendment took effect.
Child-related terms. They remain modifiable (3105(b)).
Modification clauses. Without one, property and alimony terms are not modifiable (3105(c)).
Beneficiary designations and wills. An agreement does not by itself update insurance or retirement beneficiaries; the decree order reminds spouses to reaffirm or change them (3323(b.1)). Our wills and estates page covers estate planning.

For example: a business owner's premarital agreement

Here is a hypothetical. Before her wedding, a woman in Chadds Ford who owns a small company signs a premarital agreement with her fiance keeping the company and its growth separate. Both attach financial statements listing assets and debts, and each has the agreement reviewed by a lawyer weeks before the wedding.

Fifteen years later, in a divorce, the husband argues the agreement is unfair. Under 3106 he must prove by clear and convincing evidence either that he did not sign voluntarily or that he lacked fair disclosure, had not waived it in writing and did not otherwise know her finances. Because full disclosure was attached and both had weeks to review, the disclosure ground does not fit these facts; if the agreement stands, the company is excluded under 3501(a)(2). The child support terms in their later separation agreement remain open to modification (3105(b)). This example only illustrates the statute; it does not predict any result.

What mistakes do couples make with these agreements?

Skipping disclosure. Missing disclosure without a written waiver is a ground to set the agreement aside if the other spouse also lacked knowledge (3106(a)(2)).
Signing at the last minute. Timing feeds a voluntariness challenge.
Assuming child support can be waived for good. Child support terms can be modified by the court (3105(b)).
Forgetting a modification clause for alimony. Without one, the court cannot change it (3105(c)).
Losing the signed original and exhibits. The disclosure attachments are often the key evidence.
Not updating beneficiaries and wills. These need separate action.

What should I do this week?

If you are planning a wedding, start the agreement months ahead.
Prepare a full list of assets, debts and income to attach.
Make sure each person has time to review it with their own lawyer.
If you have an agreement and are divorcing, find the signed original and all exhibits.
List the property you believe the agreement excludes.
Book a consultation to review enforceability.

Frequently asked questions

Can a postnuptial agreement exclude property?

Yes. Property excluded by a valid agreement entered before, during or after the marriage is not marital (3501(a)(2)).

Does each spouse need a lawyer?

The statute does not require it, but independent review helps show the agreement was signed voluntarily and with adequate knowledge.

Can a prenup decide custody?

Custody and child support terms can always be modified by the court on changed circumstances (3105(b)); see how judges decide custody.

Is an agreement enforceable if it was never filed with the court?

Yes. It can be enforced with Divorce Code remedies whether or not it was merged or incorporated into the decree (3105(a)).

What should I bring to a consultation about my agreement?

The signed agreement, all exhibits and any financial disclosure; see what to bring to a divorce consultation.

Call Giribaldi Law at (610) 891-8303 or contact us online for a free consultation about a prenuptial or postnuptial agreement. Evening and weekend appointments are available.

Is a prenuptial or postnuptial agreement enforceable in Pennsylvania?