Questions people ask
How long is a prenup good for?
The short answer
A prenuptial agreement generally stays in force until the marriage ends or both parties change it in writing, unless the agreement itself sets an end date. Whether a particular agreement is enforceable is a question for a family-law attorney.
The longer answer
That is the practical argument for storing the original properly. An agreement signed in your twenties may be read for the first time in your fifties, by people who were not in the room when it was signed. The attorneys may have retired. The accounts listed on the schedules may have been renamed, moved or closed.
Some agreements set their own limit: a date, an anniversary, or an event after which certain terms change or fall away. Those clauses are easy to forget precisely because they sat quietly for years. Read your own agreement for one, or ask the attorney who drafted it what it says and whether anything has already been triggered. If there is no end date, confirm that with counsel rather than assuming it.
A long marriage also changes what the agreement is being measured against. The house on the schedule may have been sold and replaced with one the agreement never mentions. The business may have tripled, closed, or passed to a child. None of that ends the agreement by itself, but it is why the original, with its schedules, is the document everyone returns to.
We store it. We cannot tell you whether it will hold, and any vault that offers an opinion on that is offering something it is not qualified to give. What we can do is make sure the paper is there, complete, when the question is finally asked.
If the agreement has been changed since
The answer above says both parties can change the agreement in writing. Every such change is a second document, and it only works alongside the first. A letter between lawyers, or an email in which both of you agree, may or may not amount to one; that is a question for counsel. The signed document is what gets stored.
An amendment signed in year twelve and kept in a different drawer from the agreement it amends creates a problem nobody sees until both are needed. Whoever reads them then may have one without the other and no way to tell which version governs. Signature dates matter here, so keep the signed originals rather than the clean drafts that preceded them. A later postnuptial agreement raises the same question in a larger form.
Keep each amendment with the original, in date order, and add it to the inventory when it goes in. If you have already signed an agreement, confirming whether any amendments exist, and where each one is, is a short job now. What a prenup is made of, schedules included, explains why the pieces need to travel together. Nobody should have to guess which pages belong to which year.