Undue Influence: Contesting a Will You Believe Was Manipulated

Undue influence means someone pressured or manipulated a person into making a will that does not reflect their genuine wishes, usually a carer, partner, or family member who held significant sway over them. It is one of the recognised grounds for contesting a will, but it is also the hardest one to prove, because the law places the burden squarely on the person challenging the will and gives them no head start. If you suspect this happened to a relative’s will, acting quickly and gathering the right evidence matters far more than it does with most other challenges.

Written by Simon Jenkins, Curtis Legal LLP (Firm SRA No. 450129, Simon Jenkins SRA No. 167489). Call us on 0800 214 216 for a same-day callback.

What undue influence actually means in will disputes

Undue influence, in the context of a will, means that the pressure placed on the person making the will (the testator) was so great that the document no longer represents their own free wishes, but those of whoever was influencing them. Undue influence is one of the five legal grounds for contesting a will generally, alongside lack of testamentary capacity, lack of knowledge and approval, improper execution, and forgery or fraud. Undue influence is different from simple persuasion. Families persuade each other about all sorts of things, and the law does not interfere with ordinary encouragement, requests, or even emotional appeals. What tips persuasion into undue influence is coercion: pressure the testator felt unable to resist, often because they were dependent on the influencer for care, company, or basic daily support.

Why it is one of the hardest grounds to prove

Unlike lifetime gifts, where English law presumes undue influence in certain relationships of trust, such as between a patient and their doctor or a client and their solicitor, there is no equivalent presumption for wills. The person challenging a will must positively prove that influence was exerted and that it overpowered the testator’s free will, rather than simply showing that the influencer had the opportunity or motive to interfere. This is a direct consequence of the leading case law in this area, and it means suspicion alone, however well founded, is never enough. Courts have long recognised that a will can look surprising, unfair, or out of character and still be entirely valid, because people are free to leave their estate however they choose. The challenge only succeeds where there is affirmative evidence of coercion, not merely evidence that the outcome was unusual.

The red flags courts look for

Because direct evidence of coercion is rare (it usually happens behind closed doors, between the testator and the influencer alone) courts and solicitors instead build a picture from surrounding circumstances. The following factors, especially in combination, tend to support an undue influence claim:

• Isolation from other family members or friends, particularly where the influencer actively restricted visits, phone calls, or contact in the period before the will was made.
• A sudden and unexplained change that departs sharply from a long-standing pattern of previous wills, especially where it heavily favours the person who arranged for the new will to be made.
• The testator’s vulnerability, whether through age, illness, bereavement, or total dependency on the influencer for day-to-day care, which lowers their capacity to resist pressure even if their legal testamentary capacity was technically intact.
• The influencer’s direct involvement in instructing the solicitor, being present at the will-writing meeting, or being present when the will was actually signed, all of which raise an obvious question about whose wishes were really being recorded.

Claims that often run alongside undue influence

Because undue influence is so difficult to prove on its own, it is common to run it together with other grounds where the facts overlap. Lack of capacity is one obvious companion claim, since a testator who was more vulnerable to pressure was often also closer to the line on mental capacity. Lack of knowledge and approval is another frequent companion, which asks whether the testator actually understood and approved the contents of the will, something that becomes doubtful if the same dominant individual controlled the whole process from instructing the solicitor through to the signing. Running these grounds in parallel gives a claim more than one way to succeed, which matters given how hard undue influence is to prove in isolation.

Time limits and practical first steps

If you are concerned a will was procured by undue influence, the first and most urgent step, before probate has even been granted, is entering a caveat at the Probate Registry, which prevents a grant of probate being issued while the dispute is resolved. You should also request the solicitor’s file notes from the firm that drew up the will, since these often record who gave instructions, who attended meetings, and any contemporaneous notes about the testator’s wishes and demeanour, which can be invaluable evidence either way. Understanding the time limits for contesting a will is essential at this stage, since the appropriate window depends on the specific ground and remedy sought, and delay can close off options that would otherwise have been available. For procedural guidance on probate applications generally, the government’s own guidance on how to contact court and tribunal services sets out the formal routes available once a dispute is underway.

Costs are also a major practical consideration before starting any claim, since the usual rule that the estate pays does not automatically apply to contested probate litigation, and who pays the legal costs when a will is contested can vary significantly depending on how the case is run and whether it settles. Taking advice early, before positions harden and costs escalate, gives the best chance of a proportionate outcome.