The prenup checklist.

• Both of you say out loud what the agreement is for. Protecting a family business, a prior marriage’s children, a professional practice, an inheritance, one person’s student debt. If you cannot articulate the purpose in a sentence, you are not ready to draft, and a court reading the agreement later will not be able to see the purpose either. The agreements that survive tend to have an obvious reason for existing. The ones that read as a general grab tend not to.
• Each of you hires your own lawyer. Not one lawyer “who will be fair to both of us.” Two. In California, an agreement is presumed involuntary unless the challenging party either had independent counsel or expressly waived counsel in a separate writing after being advised to get one. In Minnesota, separate counsel is mandatory for a postnup. In Colorado and North Dakota, being denied access to counsel is a standalone ground to void. If the wealthier party is paying for both lawyers, that is common and generally fine — but the second lawyer must be chosen by, and answerable to, the other person.
• Build the disclosure schedule before anyone drafts a clause. This is the step people skip and it is the one that kills agreements. See the next section.

A prenup is an agreement to give something up. A court will not enforce a giving-up by someone who did not know what they were giving up. What counts as “knowing” is where states diverge sharply.

• List every asset with a real number and a date. “Various brokerage accounts” is not disclosure. “Schwab account ending 4471, $312,880 as of 14 March 2026” is.
• Value the illiquid things honestly, and say how you valued them. A private business at book value is the single most common disclosure failure. If a real valuation is not practical, say so in the schedule and say what basis you used — a stated method beats a bare number.
• Do not omit the things that have not happened yet. Unvested equity, a pending inheritance, a deferred bonus, an expected distribution. These are exactly what the fight will be about in twenty years.
• List the debts too. Disclosure runs to “property and financial obligations” in almost every statute. Undisclosed debt cuts against the person who hid it just as much as undisclosed wealth.
• Attach the schedule to the agreement and have both people initial every page. Then keep a complete signed counterpart each, with the schedule attached. An agreement whose schedule cannot be produced later is an agreement with no disclosure.
• Know which standard your state uses, because it changes the stakes enormously. Under the 1983 uniform act, a disclosure failure alone is not enough — the challenger must also prove the whole agreement was unconscionable when signed. Under the 2012 act (Colorado, North Dakota) and in states like Iowa and Connecticut, inadequate disclosure is a standalone ground. Utah is the far end: it requires proof of fraud, not mere unfairness.

• Exchange drafts in writing and keep every version. A negotiation record with both sides’ markups is powerful evidence that the agreement was bargained rather than handed over. Its absence is evidence of the opposite.
• Make sure the weaker-position party asks for changes, and gets some. An agreement that came back unchanged from the other side looks like an ultimatum in hindsight, even when it was not.
• Decide the spousal support question deliberately. This is the clause with four different legal answers depending on your state — void in Iowa, floored by public assistance in most, requiring independent counsel in California, entirely unfloored in South Dakota. Read your state’s row on the main guide.
• Talk about a sunset or a step-down. Not required anywhere, but agreements that soften over a long marriage — a waiver that erodes after ten years, a fixed payment that grows with the years married — are dramatically easier to defend later, and they are the honest answer to “this was fair in 1999 and grotesque in 2026.”

• Sign at least thirty days before the wedding, and further out if you can. Only California and Minnesota put a number in the statute, and both use seven days. Treat seven as a floor that two states happen to have written down, not as a target. Everywhere else timing is evidence of duress, and a month of daylight is cheap insurance. California’s seven days runs from first presentation of the final agreement to signing, and since 1 January 2020 it applies even if you had your own excellent lawyer. Minnesota’s seven days runs to the wedding and shifts the burden of proof rather than voiding outright.
• Sign on different days, in different rooms, each with your own lawyer present. Free, and it removes the whole picture of one person signing under the other’s eye.
• Get the formalities exactly right for your state. New York is the trap here: signatures must be acknowledged to the standard required to record a deed. A merely witnessed New York prenup is not a prenup.
• Have each lawyer write a short letter confirming they advised their own client. Not required by statute anywhere we found. Enormously useful fifteen years later when the question is whether advice was actually given.
• Both of you keep an original. Store them separately.

• Actually live by it. Commingling the separate account the agreement says is separate is the quiet way people undo their own prenup. If the agreement says an account stays yours, do not run joint expenses through it.
• Revisit it when something structural changes. A child, a career ended to raise that child, a business sold, a move to another state. A move matters more than people expect — you may have signed under one state’s rules and be divorcing under another’s.
• Amend only in a signed writing. Every statute we read requires it, and every statute we read makes an amendment enforceable without new consideration. Nothing informal counts.

The steps above work everywhere. These are the rules that change by state — a waiting period written into the statute, whether a lawyer is required, and how the state treats a waiver of spousal support, which is the clause most likely to be thrown out. Two states put a number of days in the statute; California goes furthest on counsel, and three states void a support waiver outright.

Waiting period and counsel columns from our state-by-state statute table; a dash means we could not confirm that state from an official source. Support-waiver column from the alimony waiver research. All read 21 September 2026.