The number of couples deciding to get a prenup is increasing, with one law firm telling Money it has seen requests double in the last year. 

It is estimated that more than 20% of all married couples in the country have signed one of these agreements.

So, what are they, and why are so many of us opting for one? The Money team took a look…

A quick rundown of what a prenup is

A prenup is a legal arrangement made by a couple before they marry or enter a civil partnership, which sets out plans for how their assets should be divided if they divorce or have their civil partnership dissolved.

They are not legally binding, but thanks to a landmark ruling in 2010, courts are expected to uphold prenups that have been entered into freely.

However, courts are still able to make decisions on a case-by-case basis, meaning prenups that appear to have been entered under pressure or written up particularly unfairly might not be given as much weight.

Four reasons why they have become more popular

The landmark ruling

Prenups used to be associated with the ultra wealthy and famous, but after the Radmacher v Granatino ruling, people became more aware of them, Charlotte Lanning from Edward’s Family Law told Money.

After that decision, prenups agreed by celebrity couples made headlines across the country, making them appear “glitzy” and desirable, she said.

“When I was first starting out, I would do prenups on the odd occasion, whereas now we always have a couple on the go each,” the associate solicitor said.

Getting married later

While the ruling was a factor, Lanning thinks the more recent increase in prenups has been driven by changes in society. People are getting married later and are less worried about looking unromantic.

“The fact that people are getting married a lot later in life… means there is more to argue over,” Lanning said, explaining that the older people are, the more likely they are to own businesses, properties or other assets.

The bank of mum and dad

A lot of her clients were also relying more on the “bank of mum and dad” to fund big purchases, such as the deposit on a first home.

Lanning said this made wealth inequities more obvious, putting prenups at the “forefront of people’s minds” before they get married.

Changing attitudes

The Marriage Foundation thinktank has been looking at prenups for years, and its founder and former judge Sir Paul Coleridge told Money that changing attitudes were a big driver in the uptick.

“The old Victorian view was that it was wrong to have people talking about what should happen when a marriage broke down when the clear intention was to stay married for life,” he said.

“I’m a convert. I felt quite strongly that it was wrong to start discussing divorce before marriage, but I have completely changed my mind.

“People do quite often want to have a discussion about what should happen in the worst case.”

He explained that despite the stereotype of a rich man paying off a younger, poorer wife, that was no longer the case either.

“You find people getting married now are very established financially and have made a great deal of money on their own, and this is men and women,” he said.

“It’s certainly not only applicable to men paying women. Nowadays, it’s very frequent to be the other way around.”

Who is signing them?

Lanning said a typical client was often a high net worth individual, but it was becoming more common for young people who are in line to receive a large inheritance to get a prenup.

“A lot of the ones I have done recently have been quite interesting because it is more to do with future inheritance,” she said.

“One of the parties that is getting married won’t necessarily have the money yet, but the prenup is to make sure that if they do receive it during the marriage, that it is protected.”

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She explained that parents can be the driving force of these agreements, with many wanting to make sure their child keeps hold of their inheritance.

Then there are divorcees. Lanning said people who used her firm for their divorce proceedings will return when they’re considering getting married for a second time.

“We see it often with second marriages, particularly if the parties have children from a previous marriage or relationship. Obviously, the older you are, the more money you’ve got because you’ve had longer to build it up.”

Sir Paul stressed that prenups were not necessary for every couple, so people should consider them carefully before signing one.

What do they include?

A prenup can cover a range of topics, with Sir Paul saying he has seen some in the US that set out bizarre requirements such as the number of times a couple must have sex.

Typically, it will cover property, savings, inheritance, stocks and shares, income, business interests, pension pots, and premium bonds.

In the UK, a prenup cannot include child custody arrangements, personal matters, illegal activities, or lifestyle issues.

When writing up a prenup, Lanning said property was the most common point of contention.

“It might specify that a home becomes joint property or it will stay separate,” she said.

“When there’s not a lot of money involved, the court will normally be looking at what the weaker financial party needs in order to rehouse.

“You will quite often have a clause in there that says after a certain number of years, you can have a specific amount to rehouse, or you can have a property in a certain area, with a set number of bedrooms.

“It just provides a bit of structure to try to temper down people’s needs,” she explained.

“There is a broad spectrum of what you can assert. The whole point of it is to try to stop arguments later down the line.”

How long do they take and how much do they cost?

The simple answer to both questions is that it completely depends on how complex the agreement is.

Lanning said the general rule is that a prenup should be signed 28 days before a couple gets married.

She said it’s “absolutely great” if people contact a solicitor about a prenup around six months before their wedding.

“That way, you can get the advice on what they do, what the process is, and then a lot of couples discuss it among themselves to decide what they want to achieve. Then they come with their practical realities, and we basically make it legal,” she said.

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“Any earlier and you risk the financial disclosure then being out of date, which doesn’t help.”

Sir Paul said that when dealing with a high net worth family, the whole process could cost upwards of £10,000.

But in typical cases, people should be thinking “in terms of thousands” for the final cost.

How should you handle having the prenup conversation?

While people are less likely to find conversations around prenups uncomfortable nowadays, talking about money can still be difficult.

Amy Harris, legal director at advisory firm Brabners Personal, said having a chat about prenups tends to be easier when the issue is family money or inherited wealth.

“A prenup is sometimes a condition of them receiving any gifts or inheritance at all; it therefore comes across less personal between the couple themselves,” she said.

“We find that having full and frank financial discussions at the start of marriage can be enlightening and a good basis upon which to start their future together – with openness and transparency and a commitment to dealing with separation as amicably as possible.

“It is also important to remember that these agreements often work both ways in terms of any provisions that protect the prior assets of one party, which can also protect the prior assets of the other.”