Testamentary Capacity Assessment
A testamentary capacity assessment is an independent assessment of whether a person has the mental capacity to make or amend a valid Will under the common law test in Banks v Goodfellow…
Read moreGUIDES
Solicitor instructions and evidence in will capacity assessments
Instructions for a will-capacity opinion should identify the proposed will, material dates, broad estate, potential beneficiaries and specific concerns, with the relevant records supplied.
Author and Publication
Author: Nellie Supports Ltd
Publication Date: 15/05/2026
Citation
Mental Capacity Act 2005, c. 9. Available at: https://www.legislation.gov.uk/ukpga/2005/9/contents
Copywright
Copywright © 2026 Nellie Supports Ltd. All rights reserved.
This article is made available for general information, education and professional reference. It may be downloaded, printed and shared for non-commercial purposes, provided that it is reproduced in full, is not altered in any way, and is properly cited as the work of Nellie Supports Ltd. This material must not be edited, adapted, sold, republished, incorporated into commercial products, or used for commercial training, assessment, report-writing or advisory services without prior written permission from Nellie Supports Ltd.
This article does not constitute legal advice, clinical advice or a substitute for a decision-specific professional assessment. Where legislation, government guidance, court forms or external professional materials are referred to, those materials remain subject to their own copyright, licensing and re-use terms.
About this guide
Instructions for a will-capacity opinion should identify the proposed will, material dates, broad estate, potential beneficiaries and specific concerns, with the relevant records supplied. The sections below explain the evidence, practical steps and limits of the assessment or process.
What’s on this page
A clear instruction helps an assessor address the proposed will and the relevant dates under Banks v Goodfellow. Supply the draft and previous wills, a broad estate summary, family context, reasons for changes and relevant medical or care records. State any pressure concerns, communication needs and intended use of the opinion. The report contributes evidence; it cannot guarantee the will’s validity or prevent a later dispute.
Why the instruction shapes the evidence
Ask a defined question about the client’s capacity to make the proposed will, rather than capacity in general. Identify the legal test and material dates, explain the intended provisions and give the context needed to consider each limb. A clear instruction supports a relevant opinion and lets the assessor identify missing evidence or work outside their expertise.
What the letter of instruction should contain
The letter should identify the client, the fact that a will is being made and its broad shape, the reason capacity is in question, any diagnosis or concern known to the firm, the timescale, and whether the report may later be used in contested proceedings. It should name the test to be applied, ask for the assessment to address each limb and confirm the practical arrangements: where the client will be seen, who else will be present, and whether the assessor should also attend or advise around execution.
The records and context to enclose
The assessor should not work blind. Useful enclosures include relevant medical records or a GP summary, earlier wills and any letter of wishes, a note of the estate's broad composition and value, the family structure including anyone being excluded or treated unequally, and the drafting solicitor's own attendance notes. The claims limb of the test cannot be assessed without knowing who has claims, and the property limb cannot be assessed without knowing broadly what the estate contains.
Contemporaneous assessment and the golden rule
The Golden Rule recommends medical involvement for elderly or seriously ill testators, with an examination recorded and the will witnessed and approved by the medical practitioner. It is a rule of good practice rather than a conclusive test of validity. Coordinate the solicitor’s attendance notes, medical input and any other capacity evidence close to the relevant instructions and execution.
Complex estates, unequal provision and excluded claimants
The legal test remains Banks v Goodfellow regardless of estate value or family conflict. A more complex estate may require clearer preparation about the property and possible claims, while exclusions or changed provisions need careful, neutral exploration of the person’s own understanding. Do not increase the threshold merely because others oppose the proposed will.
Timing the assessment around instructions and execution
Capacity is time-specific, and the law recognises that a testator who gave capacitous instructions may validly execute a will prepared upon them even if capacity has declined by execution, provided they understand they are executing the will they instructed. Where a client's condition is progressive or fluctuating, assessment at the point of instructions, with a shorter confirmatory check at execution, closes the gap a challenger would otherwise exploit and keeps the evidence aligned with how the will was actually made.
What the report gives the solicitor
A strong testamentary capacity report sets out the test, the sources reviewed, the practicable steps taken, the client's own explanation of their estate, their family and their reasons, the analysis against each limb and a clear conclusion. It sits on the will file alongside the attendance notes, and if the will is ever challenged, it is contemporaneous, independent, decision-specific evidence from a professional assessor, which is precisely the evidence probate disputes so often lack.
Contested contexts and CPR Part 35
Where civil proceedings are anticipated, discuss the intended use, relevant expert-evidence rules and any permission requirement with the solicitor before instruction. CPR Part 35 and its Practice Direction govern civil expert evidence; Court of Protection proceedings have their own rules. The expert’s duty to the court, scope, sources and limitations should be clear. Cost and admissibility cannot be inferred from a provider’s report label.
Key takeaway
Identify the will and dates, the test, estate and family context, relevant records, communication support and concerns that require exploration. Agree responsibilities around execution and any medical input. Keep the report with the solicitor’s contemporaneous notes; the court will weigh all the evidence if a later dispute arises.
Frequently asked questions
Does a diagnosis automatically mean someone lacks capacity?
No. Diagnosis, age or family disagreement alone does not decide testamentary capacity. For a person’s own will, consider each limb of Banks v Goodfellow at the relevant time, with suitable communication support. The Mental Capacity Act framework for a statutory-will application is a separate question.
What evidence helps with testamentary capacity?
Send the draft will, previous wills, a broad estate summary, relevant medical records or consent to obtain them, the family and beneficiary context and any attendance notes recording earlier instructions. The assessor should confirm what was received and reviewed, because the reviewed-material list is one of the first things a challenging party examines.
When might a formal opinion be useful?
A formal assessment is most valuable where the will departs from earlier wills or expectations, where a diagnosis raises doubt, where the estate is complex, where family conflict is foreseeable, or where the testator is elderly and the golden rule points to contemporaneous capacity evidence. A conclusion about one decision does not establish capacity for another.
Related mental capacity assessment pages
The related pages below explain connected decisions, evidence requirements and legal processes.
Testamentary Capacity Assessment
Testamentary assessment costs for complex estates in England
Testamentary assessments for clients with complex financial structures
Read guide
Practical next steps
Before seeking a report, write down the exact decision, relevant date, reason for concern and intended use. Gather the documents that explain the real options and any communication needs. Check any required form or court direction, agree the scope and total fee, and clarify how missing evidence or further questions will be handled.