A will made because someone was coerced into it is not valid. But undue influence in will cases means something much narrower than most people assume, and it is one of the hardest grounds to prove in English law. Suspicion is not enough. Neither is persuasion.
What counts as undue influence?
Coercion, and nothing else. The Court of Appeal put it plainly in Rea v Rea (2024): undue influence "raises the question of coercion, and that only". The pressure has to override the person's own choice, not just talk them round.
The classic distinction, quoted in that case, is between influence that is fine and influence that is not. Persuasion, appeals to affection or family ties, appeals to gratitude for past help or pity for future hardship: all of that is legitimate. Pressure of any kind that overpowers someone's will without convincing their judgment is not.
So a daughter who keeps telling her mother she deserves more than her brother is not exerting undue influence. A daughter who makes her mother's daily life unbearable until she gives in may well be.
Does it matter how frail the person was?
Yes, a lot. What counts as coercion depends heavily on how strong and well the person was. In Edwards v Edwards (2007) the court made the point plainly. Simply talking to a weak and feeble testator may tire the brain so much that a sick person gives in for the sake of peace and quiet. A drip-drip approach can be very effective at wearing someone down.
Behaviour that would be harmless with a robust person can be coercive with a frail one.
Why is it so hard to prove?
Three reasons, and they stack up.
- There is no presumption. With gifts made during someone's lifetime, the law can assume undue influence from a relationship of trust and a transaction that needs explaining. For wills there is no such assumption. You have to prove it every time.
- The evidence is nearly always circumstantial. Coercion happens behind closed doors, and the one person who could describe it has died. Courts accept this and let you build the case from surrounding facts.
- But those facts have to do a lot of work. This is the point that catches people out. The circumstances must show undue influence was more likely than any other explanation. It is not enough that they fit with coercion.
Rea v Rea shows what that means. The trial judge found undue influence. The Court of Appeal overturned it and let the will through. There was no direct evidence of coercion, and the facts fitted just as well with the woman making up her own mind, or simply being encouraged to change her will.
What does a successful case look like?
They do succeed, but the facts tend to be extreme. In Whittle v Whittle (2022) a daughter repeatedly told her seriously ill 92-year-old father that his son had stolen money and was a violent man who assaulted women. She changed the locks to limit the son's visits, changed the recorded next of kin, and repeated the accusations to the will-drafter in her father's hearing the day before the will was made. The court set the will aside for undue influence and for fraudulent calumny.
For another example, see our write-up of the Dalton will dispute.
Is the law about to change?
It might. The Law Commission concluded in its May 2025 report that the current law does not protect vulnerable people well enough, because the evidence is usually hidden and the bar is high. It recommended that courts should be able to infer undue influence where there is evidence giving reasonable grounds to suspect it.
That would be a real shift in favour of challengers. But it is only a recommendation, and it is not law. We cover the full set of proposals in the biggest shake-up in will law for nearly 200 years.
What should you do about it?
If you are making a will and worried someone will later say you were pressured, the answer is a clear note written at the time, made when you were seen on your own. See protecting your will from a challenge.
If you think a will was the product of coercion, be realistic about what you have to prove and get specialist advice early. See how to challenge a will. It is also worth checking whether the facts fit knowledge and approval, which is often easier to run. The overview of legal challenges to wills compares the grounds.
This article is for general information and is not legal advice. If you are worried about a will made under pressure, please get in touch for advice on your own situation.
Sources
Common questions
What counts as undue influence in a will?
Coercion, and nothing else. The pressure has to override the free choice of the person making the will, not just talk them round. Persuasion, appeals to affection or family ties, appeals to gratitude for past help or pity for future hardship are all legitimate and do not invalidate a will. What counts as coercion depends on how strong and well the person was, so behaviour that would be harmless with a robust person may be coercive with a frail one.
Is undue influence presumed if a carer inherits everything?
No. Unlike gifts made during someone's lifetime, there is no presumption of undue influence in will cases. Even where a carer or someone in a position of trust gets the whole estate, the person making the accusation has to prove coercion. That is one of the main reasons this ground is so hard to establish, and it is the point the Law Commission recommended changing in May 2025.
How much evidence do you need to prove undue influence?
The standard is the ordinary civil one, on the balance of probabilities, but courts want solid evidence for an accusation as serious as coercion. Direct evidence is rare, so most cases are built on surrounding facts. Those facts have to show that undue influence was more likely than any other explanation. Facts that merely fit with coercion are not enough.
Is the law on undue influence changing?
It might. The Law Commission published its final report on modernising wills law in May 2025. It recommended that courts should be able to infer undue influence where there is evidence giving reasonable grounds to suspect it. That would make claims considerably easier to bring. It came with a draft Bill, but it is not law yet.
Oliver Asha
Solicitor · TEP · Founder of Make a Will
Oliver is a Solicitor (SRA number 372772) and a Trust and Estate Practitioner (TEP). He qualified in 2006 and he is founder at Make a Will, Make a Will Online, Digilegal Trustees and Capacity Vault. It is his mission to bring proper, solicitor-checked wills within reach of every family. He personally drafts and oversees the review of many of the guides on this site.
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Further Reading
- Stop a Probate Application - GOV.UK How to enter a caveat if you want to challenge a will
- Find a Solicitor - The Law Society Search for a solicitor who specialises in contentious probate
- Inheritance (Provision for Family and Dependants) Act 1975 - legislation.gov.uk The Act that lets family and dependants claim reasonable provision
- Wills Act 1837, section 9 - legislation.gov.uk The signing and witnessing rules a will must satisfy