While a Will is generally considered the final word on a person’s wishes, the law recognizes that humans are fallible. Under Section 20 of the Administration of Justice Act 1982, the High Court has the power to rectify a Will if it fails to carry out the testator’s intentions due to a “clerical error” or a “failure to understand instructions.” This is a vital safety net for beneficiaries who find themselves disinherited by a simple typo or a solicitor’s administrative blunder. However, the window for action is extremely narrow, typically just six months from the Grant of Probate—and the court cannot fix errors regarding the legal effect of the words used. This article explains how to identify a fixable mistake and the high bar of evidence required to correct it.

The Law of Rectification: Section 20 of the AJA 1982
Before 1982, if a Will contained a mistake, the court’s powers were severely limited; they could delete words but could not add them. This often led to “nonsensical” Wills where the deceased’s true intentions were lost to a slip of the pen.
The Administration of Justice Act 1982 (S.20) changed this, granting the court the discretion to rewrite parts of a Will to match the testator’s true intentions. To succeed, you must prove two things:
- The Intention: What the deceased actually wanted to happen.
- The Error: That the Will failed to reflect that intention because of either a clerical error or a failure to understand instructions.
1. The “Clerical Error”: More Than Just Typos
A “clerical error” is an inadvertent slip made during the process of recording the Will. Traditionally, this meant things like misspelling a name or adding an extra zero to a cash gift (e.g., £10,000 instead of £1,000).
However, the landmark Supreme Court case of Marley v Rawlings [2014] vastly expanded this definition. In this case, a husband and wife accidentally signed each other’s identical “Mirror Wills.” The court ruled that handing the wrong document to the wrong person was a “clerical error” in the office work of the solicitor. This allowed the court to rectify the Will, saving the inheritance for the intended beneficiary.
Examples of Clerical Errors:
- Accidentally omitting a clause that was present in the draft.
- Mixing up “numerator” and “denominator” in a share calculation.
- Typographical errors that change the meaning of a sentence.
2. Failure to Understand Instructions
This occurs when a testator gives a clear instruction—for example, “I want to leave my house to my nephew, John”, but the solicitor records it as “I leave my house to my brother, John.”
If the solicitor’s meeting notes (the “Attendance Notes”) clearly show the instruction was for the nephew, but the Will says the brother, the court can rectify the document because the drafter failed to understand or accurately record what they were told.
3. The “Legal Effect” Trap: What the Court CANNOT Fix
This is the most common reason rectification claims fail. The court cannot rectify a Will if the solicitor understood the instructions but used words that didn’t have the legal result the testator expected.
If a solicitor deliberately chooses a specific legal term (like “Issue” instead of “Children”) believing it achieves the testator’s goal, but that term actually excludes certain people, that is not a clerical error. It is a mistake of law. In these cases, the Will stands as written, and the beneficiaries’ only recourse is a professional negligence claim against the solicitor for the loss of their inheritance.
4. The Evidence: The Solicitor’s File
To win a rectification case, you need “convincing” evidence. The court will not change a Will based on a family member’s “hunch” or a conversation that happened 20 years ago.
The most critical evidence is the Solicitor’s File. This includes:
- Initial Instruction Notes: Handwritten notes taken during the first meeting.
- Draft Versions: Showing how the wording changed over time.
- Correspondence: Emails or letters from the deceased saying, “I noticed a mistake on page 2, please fix it.”
If the solicitor admits they made a “silly mistake” (as happened in Marley v Rawlings), the case becomes significantly stronger.
5. The 6-Month “Cliff Edge”
The time limit for a rectification claim is exceptionally strict: 6 months from the date the Grant of Probate is issued.
If you discover a mistake after this deadline, you must ask the court for special permission to bring a claim “out of time.” The court is often reluctant to grant this if the estate has already been distributed to beneficiaries. If you see an error, you must act the moment the Grant is issued to “freeze” the estate and protect your position.
Read our guide for in-depth information about why time is not friend: Immediate Action: The Crucial Difference Between a Caveat and a Claim (and Why Time is NOT Your Friend)
You Don’t Have to Face This Alone
As a team of expert solicitors, we are here to offer you the support you need to navigate this process. Don’t face this alone and contact us today to start this journey together.
Get your free, no-obligation case assessment. Call 08002980029 or visit contestawilltoday.com
FAQs
1. What is the difference between “Construction” and “Rectification”?
“Construction” is when the court looks at an ambiguous phrase (e.g., “my favorite nephew”) and tries to figure out what it means from the context of the Will. “Rectification” is when the court admits the wording is wrong and physically changes it to reflect the testator’s actual instructions.
2. If all the beneficiaries agree there is a mistake, do we still have to go to court?
Not necessarily. If everyone affected by the mistake is an adult and agrees to the change, you can use a Deed of Variation. This is a private contract that reshuffles the inheritance without needing a judge. However, if any beneficiaries are children or lack mental capacity, you must get a court order for rectification.
3. Who pays the legal costs for fixing a solicitor’s mistake?
Usually, if a solicitor admits to a clerical error, their professional indemnity insurance will cover the costs of the rectification application. If they contest it and lose, the court may order the solicitor (or their firm) to pay the costs personally because the litigation was only necessary due to their original blunder.


