Undue Influence and Wills: What It Means

Undue influence over a will means someone was coerced into making or changing it against their genuine wishes, so the document reflects another person's intentions rather than their own. It is one of the grounds on which a will can be challenged in England and Wales after the person has died.

The line between fair persuasion and unlawful coercion matters a great deal, because only coercion invalidates a will. This guide explains what undue influence means, how it differs from ordinary family pressure, who has to prove it, and how a will can be challenged. It forms part of our wider guide to contesting a will. The law described here is that of England and Wales and is current as at July 2026.

What is undue influence in a will?

Undue influence is pressure so strong that it overpowers the free will of the person making the will, so they act against their own judgement to satisfy someone else. It is more than persuasion or the ordinary sway of a close relationship. The influence must amount to coercion, whether through threats, isolation, or exploiting a vulnerable person, so that the will records the influencer's wishes rather than the testator's own (Law Commission, as at July 2026, subject to change).

Undue influence compared with ordinary persuasion

Not every attempt to shape a will is unlawful. A person is entitled to be persuaded, argued with, or appealed to on grounds of affection or duty, and a will made after that kind of pressure can still be valid. What tips persuasion into undue influence is coercion: pressure that overbears the maker's own volition rather than convincing them. The distinction turns on whether the person still exercised a genuine choice.

Because the two can look similar from the outside, courts examine the whole picture, including the person's health, dependence and the circumstances in which the will was made.

What are the warning signs of undue influence?

There is no checklist that proves undue influence, but certain patterns can raise concern and are often examined together. Courts and advisers tend to look at the person's vulnerability, their dependence on the person who benefits, and any sudden or unexplained change from an earlier will. None of these on its own establishes a claim, and each can have an innocent explanation, so they are weighed as part of the overall picture rather than treated as proof.

• A significant or unexpected change to a long-standing will, especially late in life or during illness
• A new will that heavily benefits a carer, new partner or one relative at the expense of others
• The person becoming isolated from family, friends or independent advisers
• The main beneficiary arranging the will, choosing the witnesses, or sitting in on instructions
• Signs of dependence, frailty or reliance on the person who gains

How is a will challenged for undue influence?

A will is not challenged during the maker's lifetime; a claim arises after death, when the will is put forward for probate. A common first step for someone who wants to investigate is to enter a caveat, which stops a grant of probate being issued while matters are looked into. A caveat lasts six months at first and can be extended, and entering one can lead to legal action and costs (gov.uk, stopping a probate application, as at July 2026, subject to change).

1. Gather information. The circumstances of the will, medical records, the will file and earlier wills are often reviewed first.
2. Enter a caveat if needed. This can pause probate while the position is investigated (gov.uk, as at July 2026, subject to change).
3. Set out the allegation. Any claim of undue influence must be pleaded specifically, with particulars of the facts relied on, rather than asserted in general terms.
4. Try to resolve it. Many disputes are settled by agreement or mediation before any court hearing, which can limit cost and delay.

Because contentious probate is complex and the burden is demanding, this is an area where many people choose to take advice from a solicitor who handles will disputes before committing to a claim.

Reducing the risk when making a will

Someone making a will can take steps that make a later allegation of undue influence less likely to succeed, though nothing can rule it out entirely. Many people choose to use an independent will-writer or solicitor, to give instructions privately without the main beneficiary present, and to keep a note of their reasons where a will departs from what family might expect. Where capacity is in any doubt, a contemporaneous medical assessment is one option some consider.

• Give instructions privately, without anyone who benefits in the room
• Use an independent professional rather than a beneficiary to arrange the will
• Keep a clear record of reasons for any unexpected change
• Where health raises questions, consider an independent capacity assessment at the time

Undue influence and wills in Scotland and Northern Ireland

This guide describes the law of England and Wales. The other UK nations differ. Scotland has its own law of succession and its own approach to challenging a will, including the concept of facility and circumvention, and it uses confirmation rather than a grant of probate. Northern Ireland has a separate but broadly similar system to England and Wales. Where an estate touches more than one UK jurisdiction, it can be worth taking advice in each. For the wider picture, see our estate planning guide and our overview of What Is Probate?

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