In England and Wales, infidelity carries surprisingly little legal weight in divorce. The courts are not designed as arbiters of virtue (or lack thereof), and since the arrival of no-fault divorce in 2022, adultery is no longer even a legal ground for ending a marriage. Yet among the super-rich, affairs can still prove extraordinarily costly, not because the law imposes punishment, but because the financial, reputational and structural consequences of a fractured marriage can ripple through businesses, trusts and family dynasties.

The legal reality of infidelity

In legal terms, the starting point is clear. Natasha Kurth, Family & Divorce partner at Wedlake Bell, explains that English courts focus firmly on financial fairness rather than personal conduct. “In strict legal terms, infidelity has no impact on the size of a financial settlement on divorce in England and Wales. The courts are not interested in punishing moral failings and, since the introduction of ‘no-fault’ divorce, adultery is no longer a ground for bringing a marriage to an end. Unless an affair is directly linked to serious financial misconduct, it will not, in itself, change the financial outcome.”

The introduction of no-fault divorce removed the need to attribute blame when ending a marriage. For wealthy couples navigating separation, the shift reinforces a legal system that prioritises asset division and financial provision over questions of personal wrongdoing.

Yet as Kurth notes, the absence of legal punishment does not mean affairs are irrelevant to the broader dynamics of divorce. “In practice, however, the picture is more nuanced. Ultra-high net worth cases normally turn on judgment calls rather than rigid formulas, for example, how assets are categorised, whether wealth has become ‘matrimonialised’, and how generously one party’s needs are assessed. An affair can poison the atmosphere, erode trust and eliminate the goodwill needed to reach a sensible and early settlement. This can result in protracted court proceedings and significantly higher legal costs.”

For couples whose wealth structures span multiple jurisdictions and complex corporate vehicles, those disputes can quickly escalate into lengthy and expensive litigation.

When private lives meet complex wealth

Among the super-rich, financial disclosure is rarely a simple exercise. Divorce proceedings may involve trusts, offshore companies, private equity holdings and international property portfolios. This elaborate web, Kurth explains, can be greatly complicated by an affair: “For globally wealthy clients, an affair can transform an already intricate disclosure exercise into something far more forensic. Financial disclosure at this level is rarely straightforward, normally involving trusts, offshore companies and complex investments, across multiple jurisdictions.”

The discovery of a relationship outside the marriage can, of course, also raise new questions about financial transparency. “An affair can expose parallel financial lives, such as undisclosed accounts, unexplained transfers, or assets acquired discreetly to support a relationship. Once uncovered, these issues can justify much deeper investigation into wealth structures that were designed to remain private. Credibility becomes a central issue, and trustees, family offices or corporate entities may find themselves drawn into proceedings as the court seeks clarity.”

For spouses reliant on the other’s wealth, uncovering the full financial picture can be difficult even in the best circumstances. As Carly Russell, a Trusts, Tax and Estate Planning (TEP) partner at Collyer Bristow, explains, the global nature of modern wealth structures can complicate matters further. “With international travel and high wealth, the options for asset protection and international structuring are unlimited. How that structuring is undertaken is dependent on the risk the spouse with the lion’s share of the assets is willing to take in terms of jurisdiction, and how much money they are willing to pay in legal costs and taxation to set up and maintain those structures.”

Such structures may involve multiple layers of trusts and corporate vehicles. “It is possible to create a complex web of trusts (with trustees having extensive powers of discretion over distribution and management) and corporate entities (with the point of control being an offshore fiduciary company). The UK has attempted to eliminate such levels of secrecy by increasing information recorded with various government online public services, but this relies on a UK connection for the asset and management. A non-UK tax resident spouse with offshore investments, even if having married in the UK, would have no obligation for disclosure with any UK body that offers public information.”

For a spouse seeking a fair settlement, that opacity can create a difficult dilemma. Russell explains: “So, what happens to the spouse relying on the financial wealth of the other? If they divorce, for any financial settlement, they would be relying on the honesty of the spouse who has engaged in complex structuring to disclose. Otherwise, they must embark on an arduous and expensive (and, a lot of the time, unsuccessful) asset tracing exercise.”

Even when courts intervene, certainty can be elusive. “With evidence of failure to not disclose, a court would be obliged to order full disclosure and spouses have been successful in court in unravelling offshore trust structures, but the question will always be whether what is found is everything. So, does that spouse reliant on the wealth of the other embark on an exercise that could find they have less than they benefit from now or risk possible financial hardship through court? Alternatively, do they rationalise that infidelity not on their doorstep can be accepted or at least endured?”

Emotional fallout and litigation risk

Although the law treats infidelity as largely irrelevant to financial outcomes, the emotional response it provokes can still shape how a divorce unfolds. Philippa Dolan, Family & Divorce partner at Collyer Bristow, says anger and resentment often influence the tone of negotiations.

“As a general rule, infidelity has no effect on a divorce settlement, however wealthy the couple. Inevitably, there are one or two caveats. For a start, the ‘innocent party’ is more likely to feel angry and vengeful and won’t want to make life easy for their former soul mate. This increases the likelihood of expensive, painful litigation as opposed to pragmatism and compromise.”

While judges aim to remain neutral, Dolan notes that human reactions cannot always be entirely excluded. “Judges are human. Although behaviour is irrelevant with no-fault divorce (the clue’s in the name), judges are inevitably influenced by the behaviour of the couple in front of them. It will never be articulated in their judgment, but UK family judges have more discretion than in many jurisdictions and we cannot assume that the sight of someone weeping in the witness box will carry no impact.”

In an era where pre-nuptial agreements are increasingly common among wealthy families, some couples are even attempting to address fidelity directly in legal documents. Dolan adds: “I have never included a no infidelity clause in a prenuptial agreement but I gather that they are beginning to creep in. There’s no useful case law on this as yet (unlike in the US), and I can’t see it making any financial difference on divorce, but the fact that couples are signing agreements promising to stay faithful may in itself encourage fidelity.”

Reputation and public scrutiny

For founders, entrepreneurs and prominent families, the consequences of infidelity may extend far beyond divorce courts. Kurth notes that reputational considerations can be more significant than financial ones.

“For founders, public figures and family business dynasties, the nonlegal consequences of infidelity often matter far more than the financial settlement itself. Divorce proceedings may be private, but reputational damage is not. Allegations can leak, unsettle investors, concern boards and disrupt carefully managed public profiles.”

Within closely held family companies, personal relationships often intersect with governance structures and succession planning. Kurth explains: “Within family businesses, an affair can fracture dynastic unity, complicate succession planning and create rifts that extend well beyond the marriage. At this level, a family lawyer’s role can overlap with reputation management, working alongside wealth advisers and PR professionals to protect a person's brand and legacy.”

Dolan agrees that reputational risk can escalate quickly, particularly in the age of social media. “Infidelity in itself is unlikely to be relevant when considering reputational damage to a business, but it certainly does if there are aggravating factors. Is there a big age gap? Does the innocent spouse have to cope with more than a broken heart and sense of betrayal? Do they have a disabled child? Are they a national treasure?”

Then, of course, there is the arrival of a third party into the marriage to contend with — and certain circumstances can trigger particularly intense scrutiny. “Does the new love interest work in the same business as the adulterer, who may have relied on the power imbalance to engineer a relationship? Social media can create a lynch mob very quickly and there may be a lot of clearing up for the reputational management team, including the departure of the guilty party from the business.”

Changing cultural attitudes

While the law remains largely indifferent to marital misconduct, cultural attitudes toward relationships among (U)HNWs are evolving.

“Among the super-rich, marriage is often approached pragmatically, reflected in the widespread use of pre-nuptial and post-nuptial agreements, sophisticated estate planning and an acceptance that relationships may change over time. For some, discretion matters more than fidelity itself,” says Kurth.

In some relationships, this pragmatism extends even further. Russell notes that changing lifestyles and international mobility have altered expectations in certain circles. “Infidelity does not always end in divorce and, in fact, we are seeing how the modernisation of a family structure and heightened international travel is leading to an acceptance, in some cases, that a married couple does not have to be exclusive. This can, however, [be under the condition] that financial support is given by the high-earning spouse and that any extra-curricular relationships are kept on the sidelines.”

Even so, privacy has become harder to maintain. Dolan points to the role of technology and social media in reshaping the risks associated with private relationships. “Being super-rich used to make it easier to conceal adulterous behaviour. Of course, nowadays it’s simply harder to operate below the radar because everyone has a phone, and social media has made privacy a lot more difficult, even for the wealthy.”

Public fascination with wealth and status means personal scandals rarely remain private for long. “There’s an extraordinary level of interest in what other people are doing – particularly if they’re famous, beautiful, notorious — or all three.”

Planning for risk

For UHNW families, the modern approach to marriage increasingly mirrors the way they manage other forms of risk. As Kurth notes, the law itself has not changed dramatically, “What has shifted is not the law, but how ultra-high net worth clients increasingly manage risk, planning in advance to ensure that their relationships do not threaten wealth, privacy or legacy.”

In other words, while infidelity may not alter the mathematics of divorce settlements, within the intricate financial and reputational ecosystems inhabited by the super-rich, its consequences can still prove rather costly.

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