What the numbers mean
The scale is clear, but the picture has a gap. HMRC reports £872 billion of adult ISA holdings for 2023 to 2024 and an average of £64,386 for holders aged 65 and over in 2022 to 2023 (HMRC, Sept 2025 release, subject to change). With value concentrated at older ages, a good deal of ISA wealth is likely to change hands on death.
What the official statistics do not do is count how many APS allowances are claimed each year. HMRC's Annual savings statistics publish ISA values, holder numbers and subscriptions, but not a breakdown of inherited ISA or APS take-up. So the honest position is that the demand side can be inferred from the size and age profile of the pool, but the actual number of inherited ISA allowances used is not published data. Any specific claim about how many people use the APS should be treated with caution unless a named source is given.
The value that can be inherited is measured. The number of people who actually claim the allowance is not published, so it can only be estimated with care.
A second observation: with the annual ISA limit held at £20,000 (gov.uk, 2026-27 tax year, subject to change) and average older holdings far above that, the APS can matter precisely because a survivor could not otherwise replace a large inherited ISA within a single year's allowance. That is general observation, not advice for any particular estate.
Trend over time
The number of ISA holders dipped recently while the number of accounts being subscribed to rose, which suggests active saving concentrated among existing holders. HMRC reports 21.3 million adult ISA holders in 2022 to 2023, down from 22.3 million the year before, and around 15 million accounts subscribed to in 2023 to 2024, up from 12.4 million (HMRC, September 2025 release, subject to change).
| Measure | Earlier year | Later year |
|---|
| Adult ISA holders | 22.3 million (2021-22) | 21.3 million (2022-23) |
| Adult ISA accounts subscribed to | 12.4 million (2022-23) | Around 15 million (2023-24) |
Source: HMRC, Annual savings statistics, September 2025 release. Reference periods as shown. Subject to change.
Sources and methodology
Every statistic on this page comes from a named official source and is quoted with its reference period. Nothing has been estimated, rounded further, or extrapolated beyond what the source states. Where the data does not exist, such as the number of APS allowances claimed, the page says so rather than filling the gap.
Frequently asked questions
What are the main inherited ISA statistics for the UK?
HMRC reports that adult ISA holdings were worth £872 billion at the end of 2023 to 2024, with 21.3 million holders in 2022 to 2023 and an average of £64,386 for those aged 65 and over (HMRC, Sept 2025 release, subject to change). HMRC does not publish how many inherited ISA allowances are claimed.
What is the additional permitted subscription?
The additional permitted subscription (APS) is an extra ISA allowance for a surviving spouse or civil partner, generally the higher of the deceased's ISA value at death or at closure for deaths on or after 6 April 2018 (gov.uk, as at July 2026, subject to change). It sits on top of the survivor's own annual ISA limit and can only be claimed once per deceased partner.
How long is there to use an inherited ISA allowance?
For a cash subscription, there is generally 3 years from the date of death, or 180 days after the administration of the estate is complete if that is later. For assets transferred in specie, the window is generally 180 days from beneficial ownership passing (gov.uk, as at July 2026, subject to change). The couple must have been living together at the date of death.
Does the APS reduce inheritance tax on an ISA?
No. The APS preserves the ISA's income tax and capital gains tax advantages for a surviving spouse or civil partner, but the ISA still forms part of the estate for inheritance tax, though spouse and civil partner transfers are generally exempt anyway (gov.uk, as at July 2026, subject to change). Inheritance tax and the APS address different things.
Can an unmarried partner inherit an ISA allowance?
Generally not. The APS is available only to a surviving spouse or civil partner who was living together with the deceased at the date of death (gov.uk, as at July 2026, subject to change). An unmarried partner may inherit the money under a will, but not the ISA allowance itself. The rules apply across the UK.
Do all ISA providers offer the APS?
No. An ISA manager is not obliged to accept an additional permitted subscription, and not every provider supports it (gov.uk, as at July 2026, subject to change). Where a provider does not offer it, some people choose to ask whether the allowance can be used with a different manager. It can be worth checking before assuming the allowance is available.
About Fairchild Oldfield
The Fairchild Oldfield team brings together estate planning, tax, independent financial advice and client care, working with families across England and Wales.
Fairchild Oldfield are estate planning specialists and will writers, not a firm of solicitors. This article is general information based on practical experience and published official statistics, not legal, tax or financial advice.
Important: This article is general information only and is not legal, tax or financial advice, and reading it does not create a professional relationship. ISAs are a regulated financial product, and many people considering them choose to seek guidance from an FCA-authorised firm or provider. The ISA rules are UK-wide, while the inheritance tax commentary reflects the law of England and Wales, and other UK nations may differ in related areas. Figures and rules are current as at July 2026 and are subject to change. Before acting, many people choose to seek advice from a suitably qualified professional, such as a solicitor, a STEP practitioner, an accountant, or an FCA-authorised financial adviser, who can consider their individual circumstances.
