Wills Trusts and Estate disputes FAQ:  How do I know if a Will is valid?

June 12, 2026

A Will can be challenged because it does not reflect the true intentions of the testator (the person making the Will) or fails to comply with legal requirements.

In order for a Will to be valid, it must meet the strict criteria as set out in section 9 of the Wills Act 1837:

  • The Will must be in writing
  • It must be signed by the testator, and they intend their signature to give effect to the Will.
  • The signature must be either made or acknowledged in the presence of at least two witnesses present at the same time.
  • Each witness must sign the Will, or acknowledge their signature, in the presence of the testator (but not necessarily in the presence of any other witness).

The law permits challenges only on recognised legal grounds — not simply because someone is unhappy with their inheritance.

The grounds are as follows:

  1. Lack of testamentary capacity:
    • the testator did not have capacity understand that they were making a Will and it’s legal consequences;
    • did not understand the extent of their property and nature of their estate;
    • did not understand who may have a claim against the estate; and
    • decision making must not be influenced by any disorder of the mind or insane delusion.
  2. Lack of knowledge and approval – the testator did not fully understand or approve of the contents of the Will
  3. Forgery — the document was forged.
  4. Undue influence — where the testator was coerced into making their will, this can be direct or subtle.
  5. Fraudulent calumny – when a person deliberately poisons a mind against another potential beneficiary by knowingly making false and dishonest statements about them, with the aim of having the testator exclude that other person from their will.

When there are concerns relating the validity of a Will a Larke v Nugus request can be sent to the solicitors who prepared the will requesting detailed information about the circumstances in which the will was made. It may also be useful to obtain copies of the Deceased’s medical records, particularly around the time their Will was executed. This is to gather evidence to understand if the testator had capacity when they executed their will.

Other disputes

Some disputes relate not to validity, but to whether the Will makes “reasonable financial provision” for dependants. These fall under the Inheritance (Provision for Family and Dependants) Act 1975 and are separate from Will validity challenges.

Will updates

The Law Commission recently carried out the first comprehensive review of Wills law in nearly 200 years, concluding in its Modernising Wills Law report and draft Bill published in May 2025.

The aim is to ensure the law is fit for modern society, to ensure it better protects vulnerable testators, and increases clarity and certainty. The report and draft bill sets out some proposed changes to the current 100 year old legislation. These are not yet in force but watch this space!

How can Herrington Carmichael help

Here at Herrington Carmichael, we are able to advise on Will validity challenges. If you have concerns or queries in relation to a will, please do not hesitate to contact our team.

Mike Pollard
Legal Director, Will, Trust & Estate Disputes
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This reflects the law and market position at the date of publication and is written as a general guide. It does not contain definitive legal advice, which should be sought in relation to a specific matter.

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