Author and Publication
Author: Nellie Supports Ltd
Publication Date: 15/05/2026
Citation
Department for Constitutional Affairs (2007) Mental Capacity Act 2005: Code of Practice. London: The Stationery Office.
Copywright
Copyright © 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.
What is a COP3 form?
A COP3 is the assessment of capacity form used in Court of Protection applications in England and Wales. It records a professional assessment of whether a person can make the specific decision or decisions covered by the application, such as managing property and financial affairs or making welfare decisions. Part A is completed by the applicant or their solicitor, and Part B by a practitioner with relevant expertise, commonly a doctor, psychologist, social worker, nurse or occupational therapist. Behind the form must sit a decision-specific assessment under the Mental Capacity Act 2005. This guide explains when a COP3 is needed, who completes it and what a properly reasoned one contains.
What the COP3 form is for
The COP3 is the assessment of capacity form used in Court of Protection applications. It provides the court with evidence that the person the application concerns lacks capacity to make the relevant decisions, most often about their property and affairs or their personal welfare. It usually accompanies an application such as a deputyship.
When a COP3 is required
A COP3 is generally needed when someone applies to the Court of Protection to be appointed as a deputy, or for another order, on the basis that a person cannot make the decisions themselves. The form establishes the lack of capacity that gives the court jurisdiction to act. Without adequate capacity evidence, an application is unlikely to proceed.
Who can complete a COP3
The form can be completed by a range of practitioners, including registered medical practitioners, psychiatrists, psychologists, registered social workers, registered nurses and other suitably qualified professionals. What matters is that the assessor understands the Mental Capacity Act test and can apply it competently to the specific decisions in question.
The assessment behind the form
A COP3 is only as strong as the assessment underpinning it. The assessor must identify the relevant decisions, apply the two-stage test, and explain how an impairment of the mind or brain causes the person to be unable to make those decisions. A form that asserts incapacity without this reasoning is vulnerable to questions from the court.
Decision-specific, not a general label
The Court of Protection deals with specific decisions, so a COP3 should address the decisions the application actually concerns, such as managing property and finances or making welfare choices. Treating capacity as a single global state, rather than examining the relevant decisions, is a common weakness in completed forms.
Property and affairs versus welfare
Applications often concern property and affairs, personal welfare, or both, and the relevant information differs between them. A COP3 supporting a financial deputyship should focus on the person's ability to make financial decisions, while a welfare application focuses on the relevant welfare decisions. The form should match the order being sought.
Currency and timing
A COP3 must reflect the person's capacity as it is now, not as it was some time ago. Courts expect a recent assessment, and an out of date form may be questioned or rejected. Where capacity fluctuates or is borderline, the assessment should say so and explain how the conclusion was reached at the time of assessment.
What a strong COP3 contains
A strong COP3 sets out the relevant decisions, the impairment identified, the functional analysis for each decision, the causal link between the impairment and the inability, the support that was offered, and a clear conclusion. It should be legible, complete and consistent, because gaps and contradictions are a frequent reason for rejection.
Key takeaway
A COP3 is the capacity evidence at the heart of a Court of Protection application. Its value lies in a properly reasoned, decision-specific and current assessment that links impairment to inability. A form completed mechanically, or by someone unfamiliar with the test, risks delay or rejection.
Frequently asked questions
Who needs to fill in a COP3?
The COP3 is not completed by one person alone. Part A is filled in by the applicant or their solicitor, describing the application and the decisions involved. Part B is completed by a professional who has assessed the person, such as a doctor, psychologist, social worker, nurse or occupational therapist with relevant knowledge of the person's condition.
Is a COP3 always needed for deputyship?
A deputyship application normally requires a COP3, because the court needs professional evidence that the person cannot make the relevant decisions themselves. The court can accept alternative forms of capacity evidence in limited circumstances, but a properly completed COP3 is the standard route and avoids delay.
Can a COP3 be rejected?
Yes. Common reasons include an assessment that addresses capacity in general terms rather than the specific decisions in the application, missing or thin reasoning, an out-of-date assessment, unexplained conflict with other evidence, or an assessor without relevant expertise. A questioned COP3 usually means delay and a further assessment.
Related mental capacity assessment pages
These internal links help readers move from this guide to the most relevant Nellie Supports service page, assessment option or legal framework page.
Need a COP3 assessment for a Court of Protection application?
Nellie Supports completes independent COP3 capacity assessments across England and Wales through a permanent employed team, with every report peer reviewed before delivery. Call 0333 987 5118 or visit the COP3 assessment service page to instruct an assessment.