ISA Additional Permitted Subscription: How It Actually Works (2026/27)
The mechanics of the Additional Permitted Subscription (APS) that lets a surviving spouse or civil partner inherit ISA tax benefits in 2026/27 — separate from the ISA's cash value.
A Tax Allowance, Not a Cash Inheritance
The Additional Permitted Subscription is one of the more misunderstood parts of ISA rules, largely because it sounds like it should simply mean "inheriting the ISA." It doesn't. The APS is a one-off extra ISA subscription allowance given to a surviving spouse or civil partner, equal in value to what was in the deceased's ISA — but it's entirely separate from who actually receives the underlying money or investments, which passes according to the will or intestacy rules in the normal way. Model your own ISA position with the
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ISA calculatorWhy the Separation Matters
Because the APS and the actual inheritance are separate, a surviving spouse gets the extra ISA allowance even in situations where the ISA funds themselves are left to someone else entirely — children from a previous relationship, for example. The surviving spouse can use their own separate savings, or money inherited from elsewhere in the estate, to fill the APS allowance within an ISA wrapper, sheltering that amount from future tax on growth and income, regardless of where the original ISA's actual cash ended up.
Flexibility on Provider
Since rules changed in April 2015, a surviving spouse generally isn't tied to using the same ISA provider the deceased held their account with. This means the APS allowance can typically be opened with whichever provider suits the survivor best, though each provider has its own process for verifying eligibility (a death certificate, marriage or civil partnership certificate, and confirmation of the deceased's ISA value are commonly required).
Time Limits to Be Aware Of
The window to use an APS allowance is generally three years from the date of death, or 180 days after the estate's administration completes if that's later — giving some flexibility for estates that take time to settle, but not an indefinite period. Given the emotional weight of dealing with a bereavement, it's easy for ISA administration to slip down the priority list, so noting the deadline early is worthwhile.
Checklist for a Surviving Spouse or Civil Partner
- Confirm the value of the deceased's ISA at the date of death to establish the APS allowance amount
- Decide whether to use the existing provider or move the APS allowance elsewhere
- Gather the documentation the chosen provider requires (death certificate, marriage/civil partnership certificate)
- Note the time window to use the allowance and don't let it lapse during estate administration
This article is general information, not financial or tax advice. Figures use 2026/27 UK ISA allowances.
Frequently asked questions
What exactly is an Additional Permitted Subscription?
An Additional Permitted Subscription (APS) is a one-off extra ISA allowance given to the surviving spouse or civil partner of a deceased ISA holder, equal to the value of the deceased's ISA at the date of death (or, in some cases, at the date the ISA is closed). It allows the survivor to shelter that amount within their own ISA wrapper, on top of their normal annual £20,000 allowance.
Does the APS have to be used with the same ISA provider as the deceased held their account with?
Not necessarily — since April 2015 rules widened this, a surviving spouse can generally use their APS allowance with a different ISA provider from the one the deceased used, giving more flexibility, though some providers have specific processes and required documentation, so it's worth checking with the chosen provider directly.
Is the APS allowance the same as inheriting the ISA's actual money?
No — these are two separate things. The money or investments in the deceased's ISA pass to whoever inherits under the will or intestacy rules, same as any other asset. The APS is a completely separate, additional ISA allowance the surviving spouse or civil partner gets, regardless of who actually inherits the underlying ISA funds — even if the money itself goes to someone else, the spouse still gets the APS allowance.
How long does a surviving spouse have to use the APS allowance?
There's generally a window of three years from the date of death, or 180 days from when the estate administration completes (whichever is later), to use the APS allowance, though the exact rules and provider deadlines can vary, so checking directly with HMRC guidance or the relevant ISA provider promptly after bereavement is advisable.
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