How to contest a will in the UK: grounds, routes and time limits

Three routes, not one

"Contesting a will" is used loosely in everyday conversation, but in England and Wales it covers three legally distinct routes, and the first task in any dispute is working out which one actually applies. You can challenge whether the will is valid at all. You can accept the will is valid but claim it fails to make reasonable financial provision for you under the Inheritance (Provision for Family and Dependants) Act 1975. Or you can enforce a promise the deceased made and you relied on, through the doctrine of proprietary estoppel. Each route has different grounds, different eligible claimants, different deadlines and different outcomes if it succeeds.

This page is the map. It explains what each route is and how the process works in general terms, and points you to our detailed guides on each individual ground. What it deliberately does not do is tell you how to run a claim or whether yours would succeed. This is general information rather than legal or financial advice, and will disputes are an area where the specifics decide everything: a contentious probate solicitor is the right person to assess an actual case. If you are simply unsure what contesting involves at the definitional level, start with our shorter companion piece, what does it mean to contest a will, then come back here for the full framework.

Route 1: challenging the will's validity

A validity challenge says the document should never be admitted to probate. If it succeeds, the estate passes under the last earlier valid will, or under the intestacy rules if there is none. English law recognises five grounds.

Ground	What it means	Detailed guide
Improper execution	The formalities of section 9 of the Wills Act 1837 were not met	See the signing rules below
Lack of testamentary capacity	The person did not have the mental capacity to make a will at the time	Mental capacity, dementia and will validity
Lack of knowledge and approval	The person did not know and approve what the will actually said	Covered in the capacity guide above
Undue influence	The person was coerced into terms that did not reflect their true wishes	Fraud, forgery and undue influence claims
Fraud or forgery	The will or signature is faked, or the person was deliberately deceived	Fraud, forgery and undue influence claims

The execution requirements are the most mechanical of the five. Under section 9 of the Wills Act 1837, a will must be in writing and signed by the person making it (or by someone else in their presence and at their direction), the signature must be intended to give effect to the will, it must be made or acknowledged in front of two or more witnesses present at the same time, and each witness must then sign or acknowledge their own signature in the testator's presence. A will that fails any of these is invalid regardless of what the person intended. A temporary rule allowing witnessing by video link applied only to wills made between 31 January 2020 and 31 January 2024 and has expired.

On burden of proof: the person putting a will forward must show it was duly executed and the testator had capacity, but where a will is rational on its face and properly signed, the law presumes both. It is then for the challenger to raise real doubt. Undue influence is different again: the person alleging it must prove coercion, and suspicion or opportunity is not enough. These starting positions shape how disputes unfold in practice, which is one reason early specialist advice matters.

Route 2: Inheritance Act 1975 claims

The second route does not attack the will at all. The Inheritance (Provision for Family and Dependants) Act 1975 lets defined categories of people ask the court for reasonable financial provision from an estate, even where the will is perfectly valid, and even where the estate passes under intestacy. Section 1 of the Act lists who can apply: a spouse or civil partner, a former spouse or civil partner who has not remarried or re-partnered, someone who lived with the deceased as a couple for the two years before death, a child of the deceased, someone treated as a child of the family, and anyone the deceased was wholly or partly maintaining immediately before death.

If a claim succeeds, the court can order lump sums, income payments or property transfers out of the estate. The will remains valid; the distribution changes. Because this route has its own eligibility tests, its own two standards of provision (a more generous one for spouses) and the strictest deadline of the three routes, we cover it fully in Inheritance Act 1975 claims explained. Scotland has no 1975 Act; instead, spouses and children have automatic "legal rights" that cannot be excluded by a will, which we explain in legal rights in Scotland.

Route 3: proprietary estoppel

The third route deals with broken promises. Where the deceased promised someone an asset (classically a farm or business promised to a family member who worked on it for years for low pay), the person relied on that promise, and they suffered detriment as a result, the court can hold the estate to the promise even though the will says something different. It is a distinct equitable doctrine with its own three-part structure of assurance, reliance and detriment, and it most often arises in farming and family business estates. Our dedicated guide, proprietary estoppel in probate disputes, sets out how these claims work.

Caveats: how probate is paused while questions are asked

None of the three routes moves quickly, so the law provides a holding mechanism. A caveat is a notice lodged at the probate registry that prevents a grant of probate or letters of administration being issued while it stands. According to GOV.UK's guidance on stopping a probate application, a caveat costs £4, can be entered online or by post on form PA8A by anyone aged 18 or over, lasts 6 months and can be extended for further 6 month periods. GOV.UK also warns that entering a caveat can lead to legal action and costs where there is no genuine basis for it, and suggests trying to reach agreement with the applicant first.

Two things caveats are not. They are not a claim: a caveat buys time to investigate, nothing more, and the applicant for probate can challenge it through a warning procedure. And they are not relevant to 1975 Act claims, which accept the will and usually proceed after a grant has issued. The full mechanics, including warnings and appearances, are in our guide to probate disputes and caveats. For context, the underlying probate application itself carries a £526 fee for estates over £5,000, per GOV.UK's probate fees page, so a caveat is by some distance the cheapest step in this whole landscape.

Time limits at a glance

Deadlines differ sharply by route. Under section 4 of the 1975 Act, a claim cannot be made more than 6 months after the grant of representation is first taken out, except with the court's permission. Validity challenges and proprietary estoppel claims have no equivalent fixed statutory deadline, but delay carries real practical consequences: once a grant issues and the estate is distributed, recovering assets from beneficiaries becomes far more difficult. That is why concerns about a will are generally raised as early as possible, and why the caveat exists. Executors, for their part, often wait out the 6 month window before distributing; our guides on executor duties and the probate process explain that side of the timetable.

Related situations that are not quite "contesting"

Several neighbouring problems get grouped under contesting but follow their own rules, and each has its own guide:

• The will cannot be found. A missing will is presumed revoked in some circumstances, but there are search and reconstruction routes first: see what to do if you can't find a will.
• A late marriage rewrote everything. Marriage revokes an existing will, which is how so-called predatory marriages can redirect an estate under intestacy: see deathbed marriages and intestacy.
• A dispute about the funeral itself. Who controls funeral arrangements is a separate legal question from who inherits: see the right to organise a funeral.

What contesting realistically involves

Most will disputes settle without a trial, often through negotiation or mediation, but the path there involves evidence gathering (medical records, the will file from the drafting solicitor, witness accounts), formal pre-action correspondence and sometimes court proceedings. Costs are at the court's discretion and the losing side can be ordered to pay the winner's, so the financial exposure runs in both directions; our guides on the cost of contesting probate and how often challenges succeed give the fuller picture. Where an estate is already in administration, our DIY vs solicitor probate calculator shows how professional handling compares for the estate as a whole; a disputed estate sits firmly at the professional end of that scale.

If you believe a will may be open to challenge, or you are an executor facing a caveat or a claim, this is a situation for a contentious probate specialist rather than a general high street firm. They can tell you which of the three routes fits the facts, what the deadlines mean for you, and whether the numbers justify proceeding at all. Our guide to what a probate solicitor does explains how the profession is organised, and we can point you towards specialists who handle estate disputes if you want a starting point.