When to Discuss a Prenup, and What It Should Include

“There’s lots of reasons why someone might want a prenup,” says Sital Fontenelle, partner and head of the Kingsley Napley family law team, speaking from her London office over video call. “But the thing to bear in mind is that it’s not always about protecting wealth. A well-drafted agreement can support both partners.” In conversation, she is calm and clear. Because while the word prenup still makes some couples gasp for air, the reality is far more generous. Thankfully, conversations around money, care and contribution have evolved.

“For many of my clients,” Fontenelle explains, “it is no different than writing a will. It is a way of thinking ahead, not because you expect something to go wrong but because you want to be thoughtful.”

There is also a surprising intimacy in having those conversations early, especially around difficult topics like money, career sacrifices, or whether you want children. “It surprises me how many couples avoid those talks until it is too late,” she says. “So many clients tell me the relationship started to unravel just a few years in. One wanted children, the other did not. And they never discussed it before marrying.” Even financial dynamics can create tension. “One partner might want to spend freely, the other wants to save. And over time, that creates resentment or feelings of lack of control,” she adds. “Being on the same page and talking about finances with honesty can save a lot of heartache.”

So, when should the conversation begin? And what should your prenup include?

Let’s start there.

“Those conversations are rarely easy, but when handled early and with mutual respect, they tend to lead to deeper understanding.”

When to Raise the Conversation

According to Fontenelle, the most successful prenups are the ones that are discussed early, long before lawyers or timelines are involved. “The easiest prenups are always the ones where the idea was raised openly and early on,” she says. “Not in the final weeks before the wedding, or prompted by a parent, but when it’s part of an honest conversation about values, family, or the future.” Last-minute agreements tend to be more emotionally fraught.

One common scenario she sees is when a family has long remained private about its wealth. Until suddenly, weeks before the wedding, they reveal that an inheritance or trust is conditional on a prenup. “The other partner may know there’s wealth in the family,” Fontenelle explains, “but not realise that a formal agreement is non-negotiable.”

By contrast, the calmest and most constructive agreements tend to begin with a quiet truth: I’ve built something I want to protect, or I would be open to stepping back in my career, but I would need to be protected financially if we have children.

Those conversations are rarely easy, but when handled early and with mutual respect, they tend to lead to deeper understanding.

When to Start the Process

Ideally, start the process at least three months before the wedding. “You may need advice from different countries depending on where you live or hold assets,” says Fontenelle. “At the minimum, give it three months, but sooner is always better.” The earlier you begin, she adds, the more time you leave to focus on joyful things like meeting your florist or choosing a dress, rather than sitting in your lawyer’s office days before the wedding.

What a Prenup Costs

Fees vary depending on complexity, assets, and whether other countries are involved, but for a straightforward prenup, expect to budget £10,000 to £20,000 plus VAT. “That would be the most basic of agreements,” says Fontenelle. “But compare that to litigation, which can easily run to £100,000 to £200,000 or more. Not to mention the emotional stress and uncertainty.”

What to Include in Your Prenup

The family lawyer outlines the most common (though sometimes also overlooked) clauses couples could include: from protecting inheritances to pets, pensions, and even heirloom rings.

1. What’s Yours, What’s Ours

The starting point for most agreements: defining what remains separate and what becomes shared.
“Anything you bring into the marriage, inherit, or are gifted usually stays separate,” says Fontenelle. “Anything you put in joint names is typically divided equally.” This also covers personal accounts, assets, or businesses.

2. The Family Home

A unique category in English law, the family home carries symbolic and legal weight. “Even if one person bought the property or paid the mortgage, the courts view it differently,” she notes. “It’s where the shared life happens, and that matters.”

3. Children from a Previous Relationship

In second marriages or blended families, clarity is key. “People often want to ringfence parts of their estate for children from an earlier relationship,” Fontenelle explains. “That can include trusts, property, or inheritance planning.”

4. Future Children & Care Roles

While you can’t predict everything, you can express how you hope to manage big decisions. “It still surprises me how often couples marry without discussing whether they even want children,” she says. “A prenup opens up space for that, including what happens if one person gives up work to raise them.”

5. Pensions & Retirement Plans

Long-term planning is just as important as wedding planning. “Ask yourselves: what does retirement look like to you? Do you expect to share pensions? How do you feel about saving?” These aren’t just financial questions, they’re emotional ones too.

6. Sentimental Objects & Family Heirlooms

It may not be about the money. “I once had a client argue over an old chair,” Sital recalls. “It wasn’t worth much, but it meant everything emotionally. You can avoid that with a clause that protects family pieces or special gifts.”

7. Engagement Rings

Often overlooked, and sometimes hotly contested. “You don’t get down on one knee and say, ‘If this ends, I’d like that back,’” Fontenelle says. “But if it’s a family ring or worth a lot, you’ll be glad you documented it.”

8. Pets

Emotionally family, legally property. “You can include who keeps the dog or cat,” she says. “Think of it like a shared car. It might sound transactional, but it avoids distress later.”

9. Jurisdiction & International Complexity

If you’re from different countries or live abroad, timing and legal clarity are crucial. “Some clients come to me weeks before the wedding because a parent suddenly insists on a prenup,” she says. “In international families, inheritance trusts often require one. And you’ll need to decide where the agreement will be valid.”

10. Privacy Measures

No one imagines divorce, but if it does happen, few want it in the press. “A prenup makes it more likely that you’ll avoid court,” Fontenelle explains. “That means avoiding public disclosure of finances and family life.” She points to the famous Paul McCartney and Heather Mills case. “Their court judgment, and financial details, were published in full. A well-crafted agreement can steer you away from that.”

11. Moral Clauses

Some couples choose to include symbolic clauses even if not enforceable in court. “Clauses around infidelity are not legally binding in England,” says Fontenelle, “but people still include them as a statement of mutual values or emotional boundaries.”

The best prenups don’t live in daily conversation. “Good agreements are long (20 or 30 pages), but you shouldn’t need to revisit them,” Fontenelle says. “Once signed, it sits at the bottom of the drawer while you go enjoy your wedding, and your life.”

Read more from our Decoding Prenups & Postnups series

The Modern Couple’s Guide to Pre- and Post-Nups

How This Couple Approached Their Prenup With Honesty and Balance