You cannot open an ISA for someone else in most circumstances. An ISA is an Individual Savings Account, tied to one person’s identity, National Insurance number, and £20,000 annual allowance, so the account holder normally has to apply themselves. There are two real exceptions: you can manage an ISA for an adult who lacks mental capacity if you hold a registered Lasting Power of Attorney or a court deputyship, and a parent or guardian can open a Junior ISA for a child under 18.
Why ISAs Are Individual by Default
The clue is in the name. ISAs cannot be held jointly, and no one can apply for one on another adult’s behalf without legal authority to do so.1GOV.UK. Individual Savings Accounts (ISAs) – Overview The tax-free treatment (no income tax or capital gains tax on returns) is attached to a single National Insurance number, and each person’s £20,000 allowance is tracked individually. You cannot pool allowances or route your savings through another person’s account.2GOV.UK. Individual Savings Accounts (ISAs) – How ISAs Work
This holds regardless of relationship. A spouse, partner, parent, adult child, or friend has no standing to open an ISA in your name. If you want to help another adult use their allowance, give them the money and let them apply themselves. The provider will verify the applicant’s identity and National Insurance number, and a mismatch causes the application to fail.3GOV.UK. How to Open an ISA as an ISA Manager
Opening an ISA for an Adult Who Lacks Capacity
The one situation where you can open and manage an ISA for another adult is when that person cannot handle their own finances. The Mental Capacity Act 2005 provides two routes: a Lasting Power of Attorney and a court-appointed deputyship.
Lasting Power of Attorney
A Lasting Power of Attorney for property and financial affairs lets the donor appoint someone they trust to make financial decisions for them. If the LPA covers financial matters, the attorney can approach a bank or investment firm and open an ISA in the donor’s name.3GOV.UK. How to Open an ISA as an ISA Manager The provider will want to see the LPA (or a certified copy), keep it on file, and check that its scope actually extends to opening investment accounts. Some LPAs contain restrictions that may not cover ISAs, so the wording matters.
Timing is the catch. An LPA has to be set up while the donor still has mental capacity, and it must be registered with the Office of the Public Guardian before it can be used. Registration currently costs £92 per LPA.4GOV.UK. Make, Register or End a Lasting Power of Attorney – Overview If capacity has already been lost and no LPA was arranged in advance, this option is closed.
Court-Appointed Deputy
Where no LPA exists and someone can no longer manage their finances, a family member or professional must apply to the Court of Protection to be appointed deputy. The application fee is £421.5GOV.UK. Court and Tribunal Fees – Updates From April 2025 Deputies then pay an annual supervision fee to the Office of the Public Guardian (£320 for general supervision, £35 for minimal), plus a one-off £100 assessment fee.6GOV.UK. Applying for a Reduced Fee for Your OPG Deputy Fees The process is slower and more expensive than registering an LPA in advance.
Deputies must file an annual report with the Office of the Public Guardian setting out the financial decisions taken and how the person they act for was involved.7GOV.UK. Deputy Annual Report Forms – Accounting for Your Actions Misusing someone’s money while acting as attorney or deputy is a criminal offence. Under the Fraud Act 2006, fraud by abuse of position carries a maximum sentence of 10 years, and theft under the Theft Act 1968 can bring up to 7 years.8Crown Prosecution Service. Theft Act Offences Courts treat these cases seriously because the victims are vulnerable.
Opening a Junior ISA for a Child
Junior ISAs are the main exception to the individual-only rule. A parent or guardian with parental responsibility can open a Junior ISA for any child under 18 living in the UK.9GOV.UK. Junior Individual Savings Accounts (ISA) – Overview The adult who opens the account becomes the registered contact and takes the investment decisions, but the money legally belongs to the child. Only someone with formal parental responsibility can sign the initial application. Grandparents, aunts, uncles, and family friends cannot open the account themselves.
Once it exists, anyone can pay in by bank transfer or cheque, up to the annual limit of £9,000 for the 2025-to-2026 tax year.9GOV.UK. Junior Individual Savings Accounts (ISA) – Overview That limit is total contributions from all sources combined. If a parent pays in £5,000 and a grandparent adds £4,000, the account has hit the ceiling for the year.
What Happens as the Child Gets Older
At 16, the child can take over as the registered contact for their own Junior ISA and start managing the account.10GOV.UK. Junior Individual Savings Accounts (ISA) – Manage an Account Withdrawals are still blocked until they turn 18. On their 18th birthday, the Junior ISA automatically converts into an adult ISA, and the young person has full access. The parent or guardian has no further say from that point on.
Inheriting an ISA From a Spouse or Civil Partner
You cannot open an ISA in a deceased person’s name, but there is a related right worth knowing about. If your spouse or civil partner held ISAs when they died, you receive an additional ISA allowance on top of your own £20,000, known as an Additional Permitted Subscription.11GOV.UK. Inheriting an ISA From Your Spouse or Civil Partner The deceased person’s ISA becomes a “continuing account” that keeps its tax-free status until the executor closes it, the estate is settled, or three years have passed, whichever comes first. Contact the ISA provider to arrange the additional subscription, as each one handles the paperwork slightly differently.
Documents the Provider Will Ask For
Whether you are opening an ISA under a power of attorney or a Junior ISA for your child, the provider needs the account holder’s details, not yours as the applicant:
- Full name as it appears on official documents
- Permanent residential address including postcode
- Date of birth
- National Insurance number (required for Lifetime ISAs and used for other types to track allowance usage)3GOV.UK. How to Open an ISA as an ISA Manager
If you are acting under a Lasting Power of Attorney, provide the original document or a certified copy. The provider will confirm it is registered with the Office of the Public Guardian and that its scope covers opening and managing ISAs. A court-appointed deputy provides the court order instead. Either way, the provider keeps a copy for HMRC audit purposes.3GOV.UK. How to Open an ISA as an ISA Manager
For a Junior ISA, expect to supply the child’s birth certificate or adoption certificate to prove your relationship and the child’s age. Most providers have dedicated Junior ISA or third-party application forms; use those rather than the standard individual form, because they include the correct fields for both the registered contact and the child.