Couples sign a prenuptial agreement based on the life they expect. Years later, that life may look different, and the agreement can start to feel out of date or unfair to one or both of them. The good news is that a prenuptial agreement can be changed after marriage. The catch is that it can only be changed in a specific way, and a change done carelessly can be worse than no change at all.
Yes, spouses can change a prenuptial agreement after marriage, but only by mutual agreement, and the change should be properly documented in writing with full financial disclosure and independent legal advice for each spouse. One spouse can't change it alone. A prenuptial agreement lawyer in Calgary can advise whether to amend, replace, or cancel it.
A prenuptial agreement is a contract, and a contract can't be rewritten by one party. If only one spouse wants a change, the other has no obligation to agree, and the original terms stay in force.
A spouse who simply starts acting as though the agreement has changed, or who signs a document the other never agreed to, doesn't change anything legally. Any real change begins with a negotiation between the two people.
The right approach depends on how much needs to change.
An agreement patched with several amendments over the years can become hard to read and full of conflicts. A single, restated agreement that expressly replaces the old one gives both spouses and any court a clear picture of what applies. If the changes are extensive, replacing is usually cleaner than amending.
A change to a prenuptial agreement isn't an informal handshake. Alberta's Family Property Act sets requirements for agreements between spouses, which generally include being in writing, being signed by both people, and involving independent legal advice for each spouse. Changes should follow the same care as the original agreement, since a defective amendment can be challenged.
Because circumstances have changed, the spouses' finances probably have too. A new agreement or amendment should be based on current, complete financial information from both people. Incomplete disclosure is one of the most common reasons an agreement is challenged, and that applies to a change just as much as to the original document.
Common reasons include:
Not every change is made in good faith or with equal footing. A spouse pressured into signing an amendment, particularly one that waives rights during a period of conflict, may later have grounds to challenge it.
Courts look at whether the change was voluntary, whether there was full disclosure, and whether independent legal advice was received. An amendment signed in the middle of a breakdown is often really a separation agreement in disguise and should be treated as one.
The spouse who wants a change can propose one, ideally with a lawyer's help, and try to negotiate. If the other spouse refuses, the agreement stays as it is. A court generally won't rewrite an agreement just because one spouse would prefer different terms. Courts can set aside terms in limited situations, usually when a divorce or separation is already underway and grounds like non-disclosure or unfairness are established, which is a different process from a voluntary change.
| Option | What It Does | Best When |
| Amendment | Changes specific terms and leaves the rest intact | A small number of terms need updating |
| Replacement | Substitutes a new agreement for the old one | Many terms need updating or earlier amendments have piled up |
| Cancellation | Ends the agreement, leaving default property rules | Both spouses want to rely on the default rules |
| No change | Keeps the original terms | Both spouses are comfortable with the current agreement |
THEBIL Family Law reviews the existing agreement, advises whether to amend, replace, or cancel it, and prepares the documents with the required formalities so the change holds up. A prenuptial agreement lawyer in Calgary who handles updates can also coordinate them with wills and beneficiary designations.
Request For A Consultation
Yes, by mutual agreement of both spouses, properly documented in writing with full financial disclosure and independent legal advice.
No. A prenuptial agreement is a contract and needs both spouses' agreement to change.
An amendment changes specific terms, while a replacement is a new agreement that substitutes for the original.
Yes, if both spouses agree in writing, after which the default property rules under Alberta law would apply.
Independent legal advice for each spouse is strongly recommended and generally expected, so the change is more likely to be upheld.
It may be challengeable if it wasn't voluntary, there wasn't full disclosure, or there was no independent legal advice.
The existing agreement stays in effect, since a court generally won't rewrite it just because one spouse prefers different terms.
Yes. THEBIL Family Law advises on amending, replacing, or cancelling agreements and prepares the documents properly.
If your prenuptial agreement no longer fits your life, it can be changed, but it should be done carefully. THEBIL Family Law can help you get it right. Book a consultation to talk through your options.
