Prenup or postnup?
Do you need a postnup instead of a prenup?
If you are already married, the answer is simple: you need a postnup, not a prenup, because a prenup can only be signed before the wedding. The harder question is what a postnup can still cover this many months or years in, from separating your assets to handling a new business or inheritance. Neptune is the lawyer-led online prenup and postnup service: both partners get their own lawyer for one flat fee.
Flat fee of $5,000 per couple. No payment to get started.
The one question that decides it
It is not about your assets. It is about your wedding date.
People often ask which agreement fits their situation, expecting the answer to depend on what they own. It does not. What you own decides what the agreement addresses; whether you are married yet decides what the agreement is called.
Not married yet
If your wedding has not happened, the agreement you sign beforehand is a prenup, regardless of how close the date is. A prenup can be revisited later, but it has to be signed before the ceremony to be a prenup at all.
Already married
If you are already married, whether by a week or by a decade, the agreement you sign now is a postnup. There is no version of a prenup you can sign retroactively. The document’s name changes because the timing changed, not because the goal did.
Side by side
Prenup vs. postnup
| Feature | Prenup | Postnup |
|---|---|---|
| When you sign it | Before the wedding | Any time after the wedding |
| Can classify assets you already own | Only what you own before the wedding | Assets and arrangements as of the marriage so far |
| Court scrutiny if ever challenged | Standard review for fairness and disclosure | Often reviewed more closely, since spouses already owe each other a duty of fairness by the time they sign |
| Independent attorney for each partner | Required for a durable agreement | Required, and often weighed even more heavily by a court |
| Can decide child custody or support | No | No |
| Cost with Neptune | $5,000 flat, both attorneys included | $5,000 flat, both attorneys included |
What a postnup can address
You did not miss the window. You have a different tool now.
Classifying what you each already own
A postnup can set out, going forward, which of your current assets, savings, and accounts belong to each of you separately, and which are shared. Couples with a "title control" approach, where whoever’s name is on an asset keeps it, often use a postnup to write that agreement down formally.
A business or inheritance that arrived after the wedding
If one of you started a business, or received or expects an inheritance, after the wedding, a postnup can address how it is treated if the marriage ends. This is one of the most common reasons couples sign one years into a marriage rather than at the start.
Spousal support
Many couples use a postnup to agree on spousal support in advance, including a full mutual waiver in some cases. Your attorney can review what a support provision needs to look like to be treated as valid where you live.
What it generally cannot retroactively undo
A postnup sets terms going forward from the date you sign it. It is not a way to erase how property was already legally treated before that date, and it cannot decide child custody or child support. Your attorney can review exactly where that line falls for your situation.
Rules for what a postnup can address, and how closely a court will review it, differ by state. Your attorney can review what is realistic for your situation before you decide what to put in the agreement.
Transparent pricing
One flat fee, whether it is a prenup or a postnup.
Each partner gets their own licensed attorney. One drafts the agreement; the other reviews it on behalf of the second partner.
$5,000
per couple, total
Rush pricing applies to prenups when the wedding is within 45 days. No payment required to get started.
Guides for you
Guides on prenup fundamentals and basics
Start with the guides other couples read before they begin, then take the next step when you are ready.
Common questions about postnups and prenups
Can I still get a prenup if I am already married?
No. A prenup is defined by its timing: it is an agreement signed before the wedding. Once you are married, the equivalent agreement is called a postnup, and it is signed after the wedding instead. The goal, protecting how you handle your finances if the marriage ends, is the same either way. Only the name and the timing change.
Is a postnup as enforceable as a prenup?
A postnup can be enforceable, but many courts look at it more closely than a prenup. The reasoning is that once you are married, you and your spouse already owe each other a duty of fairness, so a court wants extra confidence that neither of you felt pressured to sign. That makes the same protections that matter for a prenup, full financial disclosure, time to review, and an independent attorney for each partner, even more important for a postnup. Rules and the exact level of scrutiny differ by state, and your attorney can review what applies to you.
What can a postnup actually cover if we never signed a prenup?
A postnup can set out how your current assets, savings, and income are treated going forward, address a business or inheritance that came after the wedding, and record an agreement on spousal support. What it generally cannot do is undo how property was already treated before you sign it, or decide child custody or child support. Your attorney can review what is realistic to address for your specific situation.
Do we each need our own attorney for a postnup?
Yes. Because courts tend to scrutinize postnups closely, having your own attorney, separate from your spouse’s, is one of the clearest ways to show the agreement was entered into fairly and that each of you understood what you were signing. Neptune connects each partner with their own independent attorney for a single flat fee, the same structure used for a prenup.
What does a postnup cost and how long does it take?
With Neptune, a postnup uses the same flat fee as a prenup: $5,000 per couple, covering two independent attorneys, one for each partner. No payment is required to get started. Turnaround is typically around 3 to 4 weeks when both partners use Neptune attorneys, though a postnup’s timeline can vary more than a prenup’s since there is no fixed wedding date driving it.