Access Compass guide
Mental Capacity (16+) & best-interests decisions: an easy guide for parents
What changes at 16, how to decide if your child can make money decisions, what 'best interests' means, and when to use Appointeeship or Deputyship.
Published by Access Compass · How we research and check guides
Who it's for: Parents & carers, Professionals
✓ Verified Last checked 7 Jul 2026. Always confirm details with the service before relying on them.
Step by step
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What changes at 16?
From 16, the Mental Capacity Act (MCA) applies. You must assume a young person has capacity unless it's shown they can't make a specific decision (e.g., running a bank account). Capacity is decision-specific and time-specific.
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How to check capacity (the two-stage test)
First: Does the person have an impairment of mind/brain (including learning disability, autism, dementia, mental health condition)? Second: Can they understand the relevant information, retain it long enough, use/weigh it to decide, and communicate a choice by any means? Both stages must be met - they lack capacity for that decision only if an impairment prevents them from making the decision.
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If they lack capacity: make a 'best interests' decision (NHS guidance)
Follow NHS best interests considerations: encourage participation (involve them as much as possible), identify all relevant circumstances, find out their past and present wishes/views, consult others who know them well (family, carers, professionals), avoid discrimination based on age/disability/behaviour, and choose the least restrictive option. Record what you considered and why your choice best protects their welfare and rights.
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Which legal route fits the money task?
Benefits only -> ask DWP to make you an **Appointee** (quick, free, no court). Wider finances (banking, savings, larger sums, Direct Payments, property) -> apply for **Court of Protection Deputyship (Property & Affairs)**. Keep using informal parental management for small day-to-day tasks where the bank allows, but expect formal authority at 18.
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Reasonable adjustments & support first
Before concluding 'no capacity', offer adjustments: clear formats, visual supports, quiet space, extra time, familiar staff, and supported decision-making. Capacity can fluctuate–review again if things change.
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Working with banks and services
Ask for their disability/vulnerable customer policy. Provide copies of deputyship/appointee letters. If they refuse reasonable adjustments or misapply MCA, seek free advice/advocacy.
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Keep it simple: a one-page record
Note the decision, information given, support used, outcome, who you consulted, and why this is in best interests. This helps with audits, Direct Payments, and complaints.